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Trio Kenwood KD-1033 turntable main bearing service

  One of my first posts in this blog was regarding the servicing of the Pioneer PL12D turntable, and that has proven to be the most popular by a significant margin. The Pioneer PL12D had its competitors, and probably the most popular alternative was the Trio Kenwood KD-1033 turntable. I use both names (Trio and Kenwood) as the company operated under different names in different markets. In the UK they were Trio, possibly because the brand Kenwood was most famous here for food blenders. 95% of a KD-1033 is similar to  Pioneer PL12D, and servicing them is very much the same process. Both are belt drive , have an AC synchronous motor,  mechanical speed change , a main bearing, sprung top deck and rubber motor mounts. the KD-1033 uses a different type of anti skate mechanism, employing a thread and weight. The plinth is shallower with an internal cross brace. One aspect that is different is the design of the main bearing, and servicing it is a little harder than a PL12D. The Pioneer main b

Restoring a Pioneer PL-12D Turntable

 I got back into vinyl records about 18 months ago, and have collected a few hundred albums, mostly second hand. I have a number of turntables (NAD 5120, Ariston QDeck, Pioneer PL12D ) which I got also second hand. I keep a few, some end up passed onto friends, some that are too far gone are kept for spares. In most cases they have required a little work to get them running again.

Last week I was lucky enough to get a Pioneer PL-12D turntable from freecycle. The lady who offered it, said that she in turn had received it from freecycle , and had replaced the belt but couldn't get on with the springiness of it, and had got a modern USB turntable. I have previously worked on one of these decks, and know what she means about the suspension system used. While this blog is specifically about this particular model of deck, many of the concepts are similar to others from this vintage. Many Japanese belt drive decks throughout the  1970's shared very similar construction, so this may be of interest even if your deck is not a PL-12D.

The deck in question was  in great condition, and very complete. Both the 45 RPM adapter and the additional screw-in balance weight (for heavier cartridges) were both included, and it came with a classic Shure M75HE Mk 2 cartridge.

I thought I'd do a short service on it. While the platter rotated, removing the platter and then turning the spindle by hand was hard, indicating maybe the grease had dried up. Also the motor made a bit of a knocking sound, again, possibly a lubrication issue, so a simple service seemed a good idea.

 Here it is as received. First thing I did was remove the headshell which uses a standard SME-style collar fitting. Just unscrew the collar and the headshell and cartridge pulls off. I placed these safely elsewhere. I decided to get a new stylus as you can't tell how much service the old one has given. Clip the arm back in its rest. If this is loose just tape it in place so it doesn't flop around. These arms are pretty good, robust and you can see if the arm bearings are OK by checking there is smooth side to side and up and down movement. Also see if by very gently twisting the arm between finger and thumb is it has any rotational movement indication loose bearings. Don't force it, just the gentlest of twists is enough. Neither PL12's I've seen have had a problem here.

I then removed the lid. if you open the lid, then hold the back either side of the hinges. You will find a slight pressure to the right disengages the lid from the hinges which use a rather clever lug system.
 I then carefully lifted off the mat which should come away from the spindle in the middle. It has a decorative metal hoop which sits in a trough in the mat,

Now you can see the platter, and a couple of holes either side , if you rotate the platter you will see where the motor spindle has the belt looped around it beneath the platter. If you slip the belt off the motor through the hole you should be able to lift the platter off, a gentle vertical lift.
If its a bit stiff some gentle pressure on the spindle with your thumb while your fingers grip the edge of the platter. Put the platter, matt and belt safely to one side.
 Here you can see the deck minus the platter. Top left you can see the motor pulley, and in front of that the speed selector mechanism which raises or lowers the belt of the motor sondle to sections with different diameters for 33 and 45. Next to the motor pulley is a little sticker, which indicates where the oil point is for the motor. This is a small rivet through the top plate to which you can apply a few drops of oil. These drop down into a trough on the top of the motor below and find there way to lubrication points inside the motor.

Gaining access to the underneath of the deck is very easy. Two screws on the top are slackened and you can then slide the screws and the brackets they connect with toward the centre of the deck. You are sliding two clamps from the wooden internal ledges they normally engage with.
 Once these are slid to the centre the deck top should be able to be tipped up. Some care is needed as the cables are captive at the back and the 4 springs are still engaged in their 4 circular recesses, but I find holding the speed selector and on/off switches on the top , I can lift the front. There may be a certain amount of "twanging" as the 4 springs  are bent and flip out of their recesses. Below we see the tidy inside.


You will notice the mains cable enters via a plate at the back, and the red& white signal cables exit nearby. An additional wire joins the EMI screen on the base to the grounding point. You could remove the rear plate, unclip the black screen wire and have full access to the top, but here for simplicity I left it as is. I found I could use a wooden hammer as a prop, with the head  inside the plinth at the front and the handle supporting the top by the front metal catch, rather like propping up the bonnet/hood of  car.





 As music is extracted from a record by transforming microscopic vibrations back into electrical signals, errant vibrations are hence the enemy of good vinyl replay. All turntables include some degree of decoupling i.e springiness,  to isolate sources of vibration from the arm and platter. The motor is one source of vibration, the surrounding environment is another. Technically there are 5 systems used in the PL-12D:

1) The metal top plate is decoupled from the wooden plinth via 4 springs, which have foam rubber dampers, rather like the suspension and shock absorbers in a car

2) The motor is decoupled from the top plate  by sitting on 3 rubber bushes via 3 retaining rods

3) The motor is decoupled from the platter via the drive belt

4) The deck sits of 4 rubber feet, though these are minimal in effect and are primary for grip and to allow air flow beneath the deck. You will see that beneath the motor is a mesh vent to allow some air circulation as the motor can get hot.

5) the record is decoupled from the platter by the rubber mat.

In the picture above you can see one of the 4 springs described in 1) with the foam plug still present. On inspection these were crumbling as can happen to foam rubber over time, and I discarded these to be replaced with new pieces of foam later. This was probably the cause of the problem the previous owner described where the deck would bounce around at the slightest nudge. This appears to be a very common problem with the PL-12D.

 Of the 4 wooden recesses in the base for the springs, two had rubber washers in. On closer inspection one had two such rubber washers in, so I had 3 washers in total. These may be to provide further decoupling, but I think it more likely they are to balance the top plate i.e act as tiny shims. I removed these and put them carefully to one side.


In the inverted picture above you can see the motor. Note the black rubber bushes, which the motor sits on via the three threaded rods.

These rubber bushes can become hardened over time and this diminishes their ability to absorb the mechanical vibration from the motor, which gets picked up by the cartridge as a background hum.

NOTE: Update 2022.  An enterprising gentleman in Sweden, Tom Silvennoinen, is selling new replacement rubber mounts made of modern silicon rubber and cast to the right size, and are a fair price. I know from the PL12D facebook group that these are excellent and remove the hum completely. I'll leave in the section below describing how I restored the originals, but for best results try these:

link to new silicon rubber mounts


It's easy to unscrew the threes rods and detach the the motor from the top plate. You need a free hand to hold the motor as its still connected by wires, and quite heavy - its well built.
I wanted to lubricate the motor. It's possible to dismantle the motor to really clean and lubricate thoroughly, but that is a more complex process. I wanted to see if I could avoid that step if possible.


Here you can see the motor with one rod removed, free from the top of the plinth

Once all the three rods are removed you can see the entire motor top plate with the three rubber bushes . The grey hole at about 10 O'clock to the central spindle is the well that the oil point drips into. I removed the 3 rubber bushes and put them to one side. I carefully applied a few drops of sewing machine oil into the oil hole. The sticker on the top plate says 2-3, but as this deck had not been used for some time I put in 6 assuming some may pass through in a flushing process. I then sat the motor carefully in the base of the plinth below where it usually hangs from the top plate.


 Here you can see the underside of the top plate. The next job while the motor is getting oiled, is to look at the main bearing. The spindle is the piece of steel rod which supports the platter and forms the rod you stick the record on. On the PL-12D the spindle is captive i.e you cannot remove it from above without first loosening a screw beneath. In the picture above you can see the brass well which the spindle sits in. The screw in the side engages with a recessed waist on the spindle preventing it from being removed from above.

 This inverted picture shows me loosening the screw. It doesn't need to be completely extracted. Eventually it will be out sufficient to allow the spindle to be extracted. Once I had removed the spindle , on inspection there was a lot of brown hardened grease on the shaft. I placed the spindle in some hot soapy water to gently remove the worst.

Inside the brass well should be two things. Some more grease, probably hardened too, and a ball bearing. It's always possible that the bearing comes out with the spindle, stuck to the end, or that a previous owner has lost it. If it is still at the bottom of the well, you either have to very carefully invert the deck, or use a soft , non-metallic implement like a small drinking straw, to extract it from the bottom of the well without scratching the sides. Once out you can clean it , again in soapy water. If you loose it or it appears to be absent its a 1/8" steel ball. I previously lost the bearing on another PL12 and got a pack of 30 from a cycling shop, they are not difficult to find cheaply.  As these ball bearings can become pitted or worn, its worth checking the old one (see Update May 2014 below). Once the ball bearing is cleaned it should be shiny and if you roll it around on a very flat surface i.e a mirror or sheet of glass, it should roll freely and quietly in any direction as you tilt it. a Worn bearing will be noisier and roll erratically, and may have a dulled colour. if in doubt replace as they are cheap for a bag of 20 from a good cycle shop or from on-line source. 1/8" steel ball bearing.


While warm soapy water got rid of some of the grease, it didn't get rid of all of it. I used Servisol Switch cleaning and some rubbing with a soft cloth to clean the spindle shaft to shining. I used the same liquid and a dozen cotton wool buds to clean the inside of the brass well until the buds were coming out clean and not yellow from grease or grey from steel filings.
 Now all the rubber bits I extracted, I put together including : the matt, the belt, the 3 washers at the base of the springs, the three bushes that support the motor. I should have included the 4 feet which screw into the base, but they looked OK and do not really need the next process.
 In a separate blog I restored a turntable mat from dull grey and hard to black and supple using Platanclene Printer Roller restorer. Again here I put all the smaller pieces in a plastic sandwich bag along with a few squirts of Platanclene , then worked the fluid into all the rubber parts, especially the bushes around where they slot into the motor top plate.
 I also sprayed Platanclene on the mat and gave it a good wipe, repeating on the other side

 While the platanclene was doing its magic, I  dropped the ball bearing back into the well and dipped the lower half of the spindle into some fresh oil, then reinserted it back into the brass bearing well.
 I use Chain saw oil, which is a little thicker, but most synthetic oils will work. Some favour  sewing machine oil. Once the spindle is back in and settled, I tightened the retaining screw on the side. The spindle now turns smoothly and easily.
  I replaced the rubber parts I'd removed from the motor, they just press and pop back into place. I reattached the motor with its 3 screw in rods. I also replaced the 3 spring washers. I don't yet have any foam rubber for the springs, I'll cover that later. I gave the plinth and top plate a wipe with a damp cloth.

Don't forget the two retaining sliding screws, then the top plate is unable to fall out of the plinth. I then replaced the platter with the belt looped over the spindle via the two access holes in the top of the platter. last of all the mat goes on with its silver ring .

 I have not yet re-attached the headshell as I am awaiting a replacement stylus and intend the final set-up of the deck as a second blog, including the foam rubber damping inserts in the four springs. This was just about the restoration of the parts


With everything back together, I left the deck running for a few hours in order that the motor and bearing lubrication could work  its way into the various parts. The motor  can get warm, which helps get the oil worked into all the dry parts.

After a couple of hours I listened close to the deck and could hear little sound from the running motor or the bearing, which indicated to me that they were running very well

Next , replacing the foam inserts, fitting a new stylus and setting the arm geometry and settings .


I found some dark grey foam rubber which had be used in the packaging of a watch. It seemed reasonably springy, some foam used for camping mattresses can be rather dense.


I cut 4 wads of foam, roughly the size and shape of the space inside the springs, and stuffed these into each of the four main springs as you see. Once this is done and the top lowered back into place, the deck looses the unmanageable springiness. The suspension is stiffer and slower, with less bounciness.

I had ordered a new replacement stylus for the M75ED cartridge. Shure no longer make this cartridge and replacement styli are made by various 3rd parties. In the end , on the advice of CliveUK from the vinyl engine forum, I elected for an N75EJ stylus from the German ebay seller elec64 which cost £18 and arrived within a few days - excellent service. The old stylus slid out , you can see it above. The new stylus plus into the cartridge. The colour is different , the new cartridge has a light green front.



 I fitted the headshell carefully back in the arm. Next thing to be tested was pitch i.e does the platter turn correctly at 33 1/3 or 45. if the pitch is out , then notes will sound too high or low in pitch. Basically everything will sound wrong. Pitch problems can be an issue with belt drive tables where the belt can slip a little if old. The motor spins at a common speed determined by the mains frequency which is 50Hz in the UK and Europe but 60Hz in the US. As the motor spins at slightly different speeds in the two countries the deck came originally with different motor spindles for different mains frequencies to achieve the correct speeds in different parts of the world. This deck was a 50Hz unit , so if there was a pitch problem, I was a bit perplexed what I could do about it.

The easiest way to measure pitch with this deck is to print off and cut out the vinyl engine pitch disc on a piece of A4. You cave to prick out the centre hole with a pin.

Next put the disc on the platter , over the spindle and start the deck. If you shine a filament light on the disc while turning , the dashed lines will appear to either move slightly one way or the other , or , ideally remain still. This is because the filament lamp is pulsing at the mains frequency creating a stroboscopic effect with the marks on the spinning disk. At the right pitch the lines will appear to remain fixed.

On this deck, when set to 45, the inner set of lines , remained still which is right, however on 33 they did not , appearing to advance clockwise. I also noticed two background noises. One a "motor boat " style gentle knocking noise from the motor, the other was a scraping sound. I wondered first if the deck lubrication was insufficient



 Two more drops into the motor. I then removed the spindle again, cleaned off the oil and tried a thicker Castrol Moly Grease , in case the noise was some scraping in the main bearing. I've used this grease before where I appeared to have some play in a bearing and it seemed to work well. It contains Molybdenum Disulphide .

Niether addressed the problem. Then it occurred to me that if the 45 speed was correct, then it wasn't an issue with the performance of the platter and spindle as they were fine at that speed.

On closer inspection through the platter I could see that the speed selector was not pushing the belt far enough u the spindle to obtain 33 1/3 speed. The belt was partially on the conical section between the different diameter sections of 45 and 33 1/3. hence the pitch issue. In addition i could see that the belt was fouling on the alloy speed selector arm that pushes the belt up and down on the pulley, but only in the 33 position. Mystery solved.


I tried tightening the screws supporting the speed selector arm. The correct thing to do would be to slacken the tiny screw in the side of the spindle/capstan and lower it a tiny amount on the motor shaft. In the end though I gently widened the  C  end of the selector arm , until it neither rubbed the belt , not left the belt half way between 33 1/3 and 45 as had been happening. The deck now spun at the correct speed as checked with the strobe disc and the rubbing noise I had heard was gone. There was still some very quiet "motor boating" noise from the motor i.e a bu-bu-bu-bu-bu, but I decided to leave that for now.

The next thing was to set the arm geometry correctly. There is a lot written about this subject, and I will not go into a great amount of detail here. Basically if you consider a record to be made of a single circular spiral from start to finish. the spiral is almost perfectly circular, and for the stylus to sit correctly in the groove, it has to be at a tangent to that circle, ideally from start to end. That would mean that the cartridge should be at 90 degrees to the radius of the LP.  If you look at the arm on the Pioneer (and about 99% of all other turntables) you will see that the arm  can only move in an arc.  It cannot be at a perfect tangent to the radius of the record from start to end as I have just described. This is a fundamental and well understood problem with LP reproduction and various ways have been devised to try and address this. One is tangentially tracking arms which slide along a rail at the back and attempt to always hold the stylus at a tangent. The other is an arm (the Garrard Zero Deck) which moves the headshell continuously. However both have had different issues and the turntable arm as found in the pioneer has been the best compromise in sound quality, whether it is S shaped as here or straight as you will see in other models.

In reality its not so much of a problem. It has long been understood that setting the arm and cartridge can be achieved  using  two points i.e two places on the record where we can achieve a reasonable equivalence to a tangent. there are several geometries that are used, but I use the simple Baerwald geometry, and like the strobe disk, Vinyl Engine has a print-out and use protractor which you can get here  . You print it off, prick out the spindle hole with a pin and lay it over the platter mat surface with the power to the deck turned off. You can see this in the picture above. Baerwald assumes that the best arrangement is that the stylus is in as best position at the start and end of the LP side. Others geometries favour 2 positions closer to the middle.


If I lower the arm I should be able to land the stylus (very carefully) on the cross lines of each position. Note having aligned the outer position I have to rotate the protractor further around to coincide with the second position. Doing this is fairly easy, however in each position the sides of the cartridge should be parallel with the grid lines on the protractor, which hopefully you can see is the case above. If they are not parallel when the stylus is over the cross, you have to make some adjustment. This is done by gently loosening the cartridge screws, not too much, just enough to be able to slide it backward and forward. You then have to experiment with different positions of the cartridge in the head shell i.e further forward or backward until you find a position where both the stylus and parallel lines are correct with the protractor.

It can be fiddly and frustrating, and may require glasses or even a magnifying glass to see, the Shure cartridge has a nice large square body, and is easier to see. Some of the Ortofon OM range have a narrow body which is even harder to see. It  might also be that for a given arm, and cartridge the cartridge has to be slightly slewed in the headshell i.e the bolts through the headshell slots are not the same distance front to back.

I have done it many times and it gets easier, and it may only need to be done once. Once you have the cartridge correctly aligned in the headshell, tighten the bolts but not too much, or you may deform the headshell .


The next thing to set is the tracking weight. This is the  weight of the stylus on the record and is measured in grams. Too low and the sound will be thin and distorted, to high and  it will sound thick and worse you will damage the stylus and your records. The manufacturers typically give a range for a given stylus. , and I tend to play safe and choose the middle , which for the Shure is 1.75 grams.

How you set and measure the weight is , again, a subject of debate. the approach described in the Pioneer user Guide (also available from Vinyl Engine) , is to adjust the balance weight - the large round silver barrel at the end of the arm. This can push on, but then should move in and out using a screw action.  You should slide that back until pressed against the balance weight and with the Zero digit aligned at the mark on the arm tube.

So rotating the arm Balance balance weight screws the weight in or out. First you find a position where the arm floats if out of the cradle and the Lower switch in the down position (and power off at the mains). It should float parallel with the record surface, neither pointing up or down. This is the balance point. Once you have found this, and with the black adjustment collar set to Zero, you have found your zero point. Now you can turn the numbered collar AND the weight together, until you set it to the designated tracking weight, in my case 1.75grams. Once this is set the arm will no longer balance but  tip downward with a  gentle force.

Now I find this approach rather to fiddly and probably inaccurate, so I use a set of digital scales which I got from Maplin or ebay for £15. They display the weight of the stylus and I adjust the balance weight assembly until I achieve the target weight, or as close as I can get it.





Once the tracking weight is set you are almost done. There are three remaining settings. First bias aka Anti-skate . On the Pioneer and many other decks this is set via a small wheel and is set to the same value as the tracking weight i.e 1.75 for me. This function compensates for the effect that inertia has on the arm, where the stylus will have greater pressure on the outside groove wall than the inside.

The last two settings are VTA and Azimuth . There are no formal means of setting these on the PL-12D, but worth checking. VTA is the angle at which the tonearm is when playing a record. Ideally the arm should be parallel with the surface of the LP when viewed from the side. Some arms allow you to set this by adjusting the height at the base of the arm, for example SME. On a deck with integral arm there may not be an adjustment for this. It may never be perfect as vinyl thickness varies.I mention it for completeness, but there is not much you can do and it should be right on the pioneer with the pioneer mat. Different mats may have a different thickness which will in turn change the height of the LP surface and hence the VTA. However , vinyl comes in different thickness's also, so it will never be perfect. On the Pioneer it was good enough

Finally Azimuth is checking the arm from the front to see that the cartridge is not leaning to either side. Some people advocate turning off the power and lowering the cartridge on a small mirror so you can see the reflection . It makes it pretty obvious if the headshell  has become twisted on the end of the arm. It may be possible to loosen and tighten a screw holding the headshell collar fastener if its out. Its shouldn't be but its always possible that a previous owner might have done something odd to the headshell and warped it. The advantage of the Pioneer is it takes SME-standard universal headshell's, so a replacement can be obtained pretty easily. A few headshell's (Ortofon and Sumiko) have an azimuth adjustable collar, but these are very expensive and if the azimuth is that far out, something else must be badly wrong. On this PL12 it was fine.



With everything set and checked , time to play some music.

The Sound is  good, the Shure cartridges have a reputation for a warm lush sound and this does not disappoint. Still a little motor noise, but this is physical rather than electrical, and the deck has less hum than any other I've tried. With no music playing if I turn the volume I need to go to around 90% till I hear any hum through the speakers.

I might at some point investigate striping down the motor , cleaning and re-lubricating, but for now I'll just enjoy

Update August 29th 2013


the deck has been sounding great, but I still believed it was playing slightly fast. I'd fixed the major speed problem earlier with the speed adjuster leaving the belt halfway between 45 and 33 on the spindle. It was running with the belt fully on the 33 part of the spindle yet it was slightly fast. I confirmed this with the strobe disc and it was audible on familiar tracks.

The previous owner  had replaced the belt, and I'd measured its circumference (lay the belt in a single line, measure and double) and it looked to be the right size. I figured I had nothing to loose by ordering a new belt and again William Thakker has specific belts for the PL-12D. I got his through his main German site as he doesn't list all his stock on his ebay site, service as good as always, about 5 days to the UK.

Comparing the new belt there were two significant differences. The Thakker belt was slightly looser, the original belt had been very tight around the inner platter surface. Also the belt was thinner. I mean thinner not narrower, so I refer to the thickness of the rubber. This was probably it, the slightly thicker belt was changing the geometry of the system of pulleys that make the deck turn at precisely 33 1/3.

it now plays at precisely the right speed confirmed by both the strobe and the ear.

Im really enjoying this combination. The Pioneer/Shure combinations is not the last word in detail and has a very warm lush sound, but I like it and its very forgiving of albums which have had a tough life. I've a few charity shop albums which I paid little for, have surface noise and scratches but I still love, and this deck really makes them sound as good as they can be.

Update November 2013


The deck has really been sounding lovely. I've been using it with both the original Shure M75 cartridge (new stylus) and a similar vintage M95, again with a replacement stylus. The M95 is a very different beast than the M75 and is much more revealing. Like the Ortofon OM20 it seems to dig deeper for bass. Its more revealing , which can be very good for great recordings. I'll keep both cartridges in headshell's so I can swap between them.

I had two minor issues with the deck I wanted to  resolve . the first was some moderate play in the tone arm bearing. Side to side and up and down movement was excellent, but when replacing headshell I'd noticed some "play" if I applied a gentle in-and-out force. gently hold the arm at the bend near the headshell and apply a very gentle movement in the direction of the arm main bearing. For example if the arm is close to its  clip, this would equate to a gentle, gentle force toward the back of the deck.

This seemed to me to be perhaps some looseness in the horizontal arm bearings which often used a ball-race system .

I opened the deck up, following the  dismantle sequence steps I details above.


In the picture above you can see where the arm wiring emerges through a brass tube. These wires are very fine and delicate so great care is needed. If I carefully applied the in- and-out force on the arm above, I could see some corresponding  tiny movement in the brass tube. It has a larger brass collar, and on inspection the brass collar is threaded i.e screwed onto the brass tube like a round nut. I believe that the wider brass collar holds tiny ball bearings in place above it and forms the lower part of the horizontal bearing .

On the side of the collar is a tiny screw, the function of which is to lock the collar in place . I wondered if age, wear,  and gradual slackening was the cause of the play here ?


I gently slackened the side screw with a very small jewellers screw drive (cross head). I found that I could then very gently tighten the brass collar with my finger tips, as one would tighten a nut.  I did this only just finger tight as too tight would create too much pressure and friction on the bearing. Using the side screw position as a reference I found that if the screw pointed to  9 on an imaginary clock face, then I could tighten it to 10 or 11, without applying any undue force.

re-tightening the side locking screw again, I  gently moved the arm. It still moved freely  side to side but the in and out play was gone . Excellent.


The other thing I wanted to explore was slight noise from the motor. This is very quiet but its a rythmic knocking noise I assume with each rotation i.e at a 50Hz frequency. Its barely audible, and then only with my ear close to the motor spindle, but I have had AC motors which were silent before, so wanted to try to achieve this.

My theory was that while the top motor bearing was getting oil, the lower bearing might have dried. Here is a picture of the motor.

PLEASE NOTE The mains lead and plug has been disconnected from the wall throughout this operation. NEVER rely on the switch on the deck as the internals will still carry live voltages .


 here you can see  a side view of the motor. While I'm sure that striping the motor and re-lubricating is probably the right thing to do, I'm not sure I could get it back together to an equivalent or better tolerance. Those bolts go right through the motor, holding together the top and bottom bearing frames and the laminates around the core. They all have to be aligned. In the picture above you can see an aluminium tooth close to the red wire inside the motor. There is a toothed gear on the base of the motor, the function of which I suspect is to act as a fan to promote air flow.


 Again here you can see the the fan from the side. My thinking was that beneath the fan there may be access to the main motor spindle. If I could get a drop of oil on that it would gravitate down into the lower well.

This requires care as squirting oil indiscriminately inside a motor will certainly damage it

Again I used my precision oiler. Gently probing with the nozzle while lifting  the motor pulley from above to create a gap where the oiler might find the lower part of the motor spindle.

Once found a single gentle squeeze, remember we are trying to get a single droplet in the right place, not flood the thing.


Putting the top back in place I plugged the deck in and ran the motor , minus the platter. The noise seems quieter, but its still present. Maybe its not a lubrication issue but one of oscillation i.e if the armature is not held firmly in place perhaps its wobbling as it rotates ?.

Its not really a problem, I can live with it. Maybe I need to find a dead PL-12D motor to practice on, which might be something to look out for on ebay.


Update December 2013

Well I couldn't resist. Spurred on by comments on my blog and from vs_music over at the vinyl engine forum, I decided to strip and clean the AC motor. This was to try and resolve some mild "knocking" sound from the motor. However it took a few goes and is still not perfect, so  this is not as simple as replacing the foam or servicing the rubber supports, and only recommended for users with nosy motors as a last resort. However I thought I'd share what I did, not every fix goes perfectly . Perhaps my motor is a little  noisy and there is nothing I can do. Your mileage may vary.

WARNING : The following procedure is only to be undertaken if you are competent with a soldering iron and understand and undertake all necessary electrical safety precautions. These decks contain Live AC mains , so all procedures are undertaken with the deck disconnected and unplugged from the AC electrical supply. If in doubt use a competent electrician or repair facility.

First of all, as above remove the mat, platter and belt and the cartridge and store safely.

Slacken and slide the two screws which secure the top plate.  Also with this process I found it useful to remove the two small bolts which hold the rear signal and power plate on. At the rear of the deck is a small metal plate through which both the signal, ground and mains wires pass. Remove the two bolts either side such that the plate can fall inside the deck..

Carefully lift off the upper plate assembly. You will find a grounding wire which connects to a tag on the base board of the deck. This pulls off, so disconnect this also and taking great care flip it over and lay it upside down such that the arm is inside the wooden plinth . Take great care to ensure the arm doesn't foul on the inside of the plinth. This seems drastic but there is not really enough room to work on the motor using the propped car bonnet/hood approach as earlier.


You can see the motor on its 3 rubber mounts. From the motor are 4 coloured wires which connect to a small circuit board.  This board has a switch which is secured in position by a metal plate. This is to select between two voltages 120v and 240 v AC.

To access the motor its easier if you can remove the motor from completely from the deck. Each wire is soldered onto a tab, which is soldered in place on the circuit board. It's probably hard to remove the wire from the tab, but I found it not too hard to remove the tabs from the circuit board by de-soldering them . I used a vacuum de-solder pump, but solder braid or wick should work.

First you need to get the circuit board off of the 4 plastic compression clips which hold it to the upper plate. these can be squeezed and the circuit board carefully prised off.


Here it's useful to use a craft stand / clamp to hold the board as you need to operate both a soldering iron and de-solder device applied to each of the 4 solder pads. in the picture above you can see a number of tabs removed. This is a gentle slow process, removing as much of the solder from each tab base as possible , then gently working loose while applying heat with the iron. Eventually I got all 4 loose and disconnected the motor from the top plate  via the 3 bolts.


Then remove the top mounting plate from the motor. This is held on by two nuts and split washers. I also remove the brass 45/33 RPM spindle which is held on by a small grub screw. Keep these and all other parts safe, I tend to use a plastic tea tray to store stuff on.

 The motor frame is held together with two bolts. These are secured by two bolts and two further nuts (now removed) held the mounting plate to the motor.

carefully remove the bolts using a good quality Philips Screw driver. These bolts are quite soft so I would not use a motorised screw driver, as it would be too easy to deform the screw head. The nut on the other side site in a recess and none of my box spanners were slender enough to be able to grip but I found the bolts came loose anyway.
 On the upper side of the motor spindle a small clear plastic washer fits tightly on the motor spindle. I slid this off and stored safely.


 Once the bolts are removed you can access the central rotor (pictured below) and remove the upper and lower bearing mounts, leaving the outer stator (pictured above)
 Here is the central rotor part. Both the rotor and stator were clean and the only treatment I gave the rotor was to wipe the two steel rod ends with a clean cloth.
Above you can see the two bolts ,  nuts and split washers, the brass 45/33 motor spindle AND the upper and lower bearing frames. These last two were the focus of my work.

 Here you can see the inside of the lower bearing. There is a bronze internal bearing into which the motor spindle sits . In the very centre you can see a mark which a wipe with a cotton bud removed. It appeared to be some black dirt in the bearing well, possibly original grease mixed with worn metal.
 Here you can see the underside of the lower bearing frame (top) and the upper bearing below with its distinctive oil trough, through which you can oil the motor. The trough sits below the oil hole on the turntable top plate. At the right end of the trough you can see a tiny lighter grey section. This is the edge of a felt collar around the bronze bearing. When you oil the deck the lubricant soaks into this felt collar which ensures that the oil stays in the bearing and does not drip down into the motor.
Here is the underside of the upper bearing frame with the bronze collar bearing clearly visible .


I wiped out any obvious dirt from the bearings with cotton buds. I then gave each bearing a good long spray with servisol contact cleaner to try to dissolve any existing lubricant in each bearing. I left the bearings to dry out on some kitchen roll, then repeated again, and again. I worked the bearings by wiggle the rotors spindle back, forward and round and round in each copper bearing, again to try to dislodge any grime.

I then left the two frames to dry out on some more clean paper kitchen roll.

Once completely dry I soaked the interiors of each with light sewing machine oil. actually filling the lower closed bearing well to the brim. I left this to soak in for 10 minutes then tipped out the excess, soaking it away with cotton buds and tapping the frames on kitchen roll. My hope was that the internal felt collars would have been cleansed and re-soaked in oil. I also decided to put a small blob (Size of a small grain of rice) of silicone grease in the lower well, as this is inaccessible when the motor is reassembled, and oil from the top trough never makes the lower bearing. I figured a tiny blob of silicone grease should keep the lower bearing reasonably well lubricated

Now reassemble the motor with the rotor in the middle and the top and bottom bearing frames, the bolts and split washers and the clear plastic washer on the spindle as before. Tighten the bolts to just tight, not  too tight.

Now care must be taken to align the end bearings in such a way that the rotor spins freely. There is some play in the precise position of the bolts and the end frames, which in turn allows the rotor to be off centre. If way off the rotor will actually rub against the inside wall of the stator. twisting the motor  enables you to judge if its freely moving.

There has to be an even gap between the rotor and to stator wall. . Its possible to have no rubbing yet still have the rotor slightly off centre. I did this, put the deck back together and had a loud knocking sound from the motor.

The best way to avoid this is to look at the motor from both ends and judge the size of the air gap around the rotor. It should be even  when viewed from both ends. This is easiest done when shining a torch from behind the motor.


In this blurred picture (sorry !) above you can see a thin but even halo around the rotor which is even on both sides . Check this from both ends. Once its seems even, it's time to tighten up the bolts.

Again check the rotor spindle turns freely.

I then reversed the above process, attaching the motor to its decoupling plate then re-soldering the 4 tabs  to the circuit board and reattaching it to the top plate via the 4 plastic push clips. The colour coding is written on the circuit board so hard to get wrong. You are looking for a good clean dome of solder on the base of each tab on the lower side of the board.

Now flip the top plate and reattach the internal lower shield on the base board, the top plate secure bolts and the plate at the back. The deck should now be as before but without the platter and cartridge.

At this point I plugged the deck in and flipped the front switch to ON-UP

The first time I did this I was disappointed to hear even louder knocking sound from the motor. However this was due to me not centring  the rotor rigorously enough (as I later did with the torch as above).

I pulled out the mains plug, then revisited the motor and loosened, re-aligned and re-tightened it without de-soldering the motor, i.e I did this with the motor detached from the bolts but still wired in place. I couldn't really face de-soldering again and I don't think the tags will take a lot of de-solder/re-solder. So you see t is technically possible to strip the motor with the stator wiring still in place, but its not as accessible. Possibly if you are uncomfortable with soldering you could consider this approach.



After carefully centring the motor, I fitted it back and plugged the deck in and flipped the switch  to "ON-UP".

Motor turned and  was almost silent, just the faintest whisper. Excellent, this was what I'd hoped for. I left it running for about 30 minutes, then suddenly it was noisy again !? Not a knocking sound, just louder.

Disconnected from the mains and revisited the motor again. I tightened the bolts a bit more and also the three bolts securing the motor beneath the top plate holding the rubber mounts. These were looser from before.

Re-connect, "ON-UP" and again silent.

Left running for about 40 minutes then knocking sound again. This time quiet and similar to my original motor-boat style sound. This was just with the motor running, no platter or belt in place.

So ....I'm sort of back to square 1. I have stripped, cleaned, re-lubed and reassembled the motor. At one point I had total success, but it has reverted to as before. I don't know if further alignment tweaking might help. This motor gets hot and I wonder if the problem is temperature related. I'll leave it for tonight and see if its quiet from cold in the morning. Its no worse than it was before I started this, so I'm no worse.

In the morning with the deck cool I tried again and there was still some slight knocking sound present so my thermal expansion idea seems to not be true. I find it odd that the motor was silent for about 30 minutes , and YES it was switched on (I have made that mistake before :)

I decided to fit the platter, mat and belt and this reduced the sound to very quiet indeed. Not silent as before but quieter than it had been, so this is progress as before. Perhaps the belt tension pulls the rotor into a better alignment or prevents the oscillation which creates the knocking sound ? I think it's also possible that the revolving platter improves the motors cooling. The underside of the platter has some features which perhaps  help to carry hot air away from above the motor. Running the motor for a while with the platter removed perhaps does not allow sufficiently rapid cooling ?  Not sure, but it's possible .

Its not perfect, but its pretty good. I'll leave it running for a few hours to see how it behaves when hot, and these motors do get hot

Update May 2014: "I hear you knocking ..."

I'd started to notice a knocking sound coming from inside the deck. It was random, maybe one knock every 10 minutes or so. Not rhythmic. It shook the whole platter and at first I wondered if the motor spindle was somehow catching on the bottom of the plinth. On investigation it wasn't. I removed the matt and took the belt off the motor. Even spinning the platter by hand , I was able to hear the knocking on at least one occasion.

After scratching my head, I decided it must be the main bearing, so I removed the platter, and loosened the side screw on the brass bearing well. I removed the spindle and fished the ball bearing out carefully, using a magnetised screw driver.

Even after cleaning the bearing looked dull and grey compared to a new bearing. I got a sheet of glass and rolled the old bearing around on it. The ball appeared to roll erratically if I tipped the glass and was quite noisy compared to a new bearing which rolled smoothly in any direction. Examining the bearing with a magnifying glass I could see that while still round, some surfaced were pitted.

I decided to replace the bearing with a new one and re-lubricate  the spindle. However the end of the spindle that sits on the bearing had a tiny dimple in it. My belief is that this was caused by wear against the worn bearing. I got this deck for free and have no idea what its history is you see. Possibly if the deck had been stored un-lubricated or run in that state it could cause wear ? Over at the vinyl engine forum, the authority on the PL12, user vs_music believes that the dimple was machined onto the bearing to better sit on the ball. I'm not so sure, as I don't see why the designer would want to increase the contact area between spindle and bearing. The point is to have the minimum point of contact.

After pondering this I asked a favour of a neighbour, who is an engineer and has access to precision lathes. He polished the end on a lather to a smooth mirror for me.

I put the new bearing and spindle back together with a few drops of sewing machine oil. At first there was some grind, but once the oil had eased around all surfaces it span smoothly. With the platter in place but no belt, if I spin the platter it will turn for several minutes from just a gentle  spin.

The knocking sound has stopped, and the deck is sounding very good indeed with a Shure M95 cartridge and Jico replacement stylus. I have just taken delivery of a Denon DL-110 to try in the deck.

Update July 2019

Received a fascinating article on servicing these decks from correspondent Dirk Sipes, reproduced here, definitely worth reading


https://mr-ives.blogspot.com/2019/07/pioneer-pl12d-service-revisited.html

Update Feb 2021

There is an excellent facebook group dedicated to the Pioneer PL12D decks, and similar.  Very friendly, lots of sharing of tips and advice,  here:

The Pioneer PL12D facebook group

https://www.facebook.com/groups/1800061146950818

Update 2022 



An enterprising gentleman in Sweden, Tom Silvennoinen, is selling new replacement rubber mounts made of modern silicon rubber and cast to the right size, and are a fair price. I know from the PL12D facebook group that these are excellent and remove the hum completely. I'll leave in the section below describing how I restored the originals, but for best results try these:


Comments

Mr Ives said…
Greetings TheDutchOwner, that is a very good question and I dont have that deck to hand.

Does these pictures help ?

http://2.bp.blogspot.com/-IVvnKg_snUc/UfT5z3mk3SI/AAAAAAAAB4A/LjnFRSCti_o/s1600/IMG_0595.JPG
http://1.bp.blogspot.com/-N3tmFnnYIZE/UfT5ElwfhfI/AAAAAAAAB2g/QBkluU4D4hk/s1600/IMG_0580.JPG

It's upside down but appears to show the wider gapped (stiffer ?) spring at the motor end as you suggest.

I think the important thing is that in the correct arrangement the top will be level, and the motor end is heavier than the arm
Anonymous said…
Hi,
I have a 12AC. It works, but the tone-arm lifter (if that is what it is called) disintegrated and was accidentally discarded before I could fashion a copy of it. It was a curved piece of black plastic that the tone-arm slid across and lifted the stylus above the height of the platter. There is a curved piece of metal there but it does not come into contact with the tone-arm because it is missing the piece of plastic that used to sit on it. I have to manually place the needle on the record as the up/down button no longer lifts the arm high enough. Do you know of anyone selling spares, or of a schematic that I could follow to make a copy? I imagine it’s the sort of thing that 3D printers could solve.
Also the foam in the dampening springs has disintegrated. Do you know what is the best density or type of foam to use to replace it? Thanks in advance for any help you can give me. I would really love to get the record player back working as I've used it for 40 years, and recently inherited it.
Thanks, John
Mr Ives said…
Hi John,

I have not taken the lifter apart, could you slide a length of clear plastic piping over the existing curved metal part, the kind of stuff you use for fish tank air feeds ? maybe I misunderstand , but sounds like without the rubber/plastic bumper the curved metal doesn't meet the underside of the arm ?

Sources of spares would be ebay or http://organdonorparts.com/ - worth a try

I didn't really give too much thought to the type of foam, and I simply used something that was to hand. I'm not sure its that important, its purpose is to dampen the springs that isolate the deck from external vibration, mainly footfalls. The motor decoupling rubber bushes are more critical I would think. I used foam that was packing with a watch, but I'd reckon the kind of sponges you use to wash a car would be fine and cheap.
Shan Dalton said…
Mr. Ives
I have spent the last 2 days reading through this blog, and to say it is packed with great inforinform would be like saying the northern lights are kinda neat! Thank you for your time. My question: motor by itself is hush quiet as well is the plate (and apins for infinity and beyond). When I belt the two together I get what sounds almost like a grinding sound. I noticed the tabs on the speed adjuadjust bar rub the belt as it's rotating. Not sure what to try
Thanks!
Shannon
Mr Ives said…
Hi Shannon, thank you for your kind words about the blog. Sounds like you have a nice example of the PL12. The problem you describe is common to a lot of decks, including my current one - a Thorens. and is fixable.

I guess if the plate spins you have cleaned out the bearing and re-oiled ? It can be a good idea to replace the existing ball bearing that's in the well as these do wear and are very cheap to replace (1/8" ball bearing - some bike shops will give you one if you ask nicely)

So with these AC belt drive decks the motor spins at a constant speed and has a puller with two different diameters on it, and a lever to shift the belt between the two sections to achieve a different gear ration and hence a different speed of main platter rotation. Its a bit like the gear change on a bicycle . I suspect that over time the motor shifts relative to the lever, possibly because the 3 rubber mounts which support the motor loose some elasticity with age - these decks are in their mid-40's.

This can cause two problems 1) the rubbing noise, which should be fairly quiet where the belt is continuously rubbing against the lever 2) The belt doesn't sit quite right on the pulley and sometimes the deck plays 33 rather too fast.


I think the best approach is to adjust the height of the pulley on the motor. It should have a brass grub screw on the side and you'll need to spend a little time, trial and error to get it right, but there should be a height where the belt sits clear of the speed adjust mech.

Another approach would be to slightly open the jaws of the speed adjuster, but I think that's only a last resort if the pulley adjust doesn't work.

Its a fiddly job as you need some trial and error and a lot of taking the platter off, putting the belt on , trying, then repeating but it will be worth it.

God luck and keep us posted how you get on

Shan Dalton said…
Problem fixed! I discovered spreading the Jaws last night after posting my question, thank you for the quick response! Very quiet now. Furthermore, what is your opinion of changing out the rca cables and power cable as others have mentioned here in this blog? Also noticed others mentioned removing the motor and submerge it in a bath of oil, what is your take on that process? The restoration is coming nicely, my father took great care of this unit so that's made things easier. Oh and before I forget to ask do you have a recommendation on a cartridge and stylus? It has, I believe, the stock cart so I figured an upgrade might be in order.
Thanks again...
Shannon
Mr Ives said…
Great Shannon, glad you are sorted.

Personally I would only change the cables if they were damaged.The red and white coax Pioneer used is perfectly good. The RCA plugs they used some times can use a gently crimp as the "petals" tend to expand a bit. As long as the connection is tight.

Ditto the mains cables. I would leave them unless they are damaged.

If the motor is silent and the deck keeps good speed (see the section on printing a strobe disc) then I would leave the motor alone. There is an oil point on the top and a few drops there from time to time is a good idea, but I would not mess with the motor without a good reason. Centering it can be a PITA.

I'm not sure what cartridge these shipped with, I'd guess maybe a Shure M75ED which is nice and you can still get replacement styli for from Jico and others. The tonearm is medium mass so probably better suited to a lower compliance cartridge.

One of the cheapest cartridges you can get is the Audio technica AT95 which is a very good modern cartridge. Also the SHure M97.


So I guess my philosophy is to concentrate on setting up the parameters of the deck as per the designers intention, so that's checking the speed, the tracking weight, alignment, VTA, azimuth. Get these right and you're good to go.

regarding the motor, I would consider doing some restoration on the 3 rubber motor mounts if they are no longer supple. I found spraying them with platanclene in a sealed plastic bag, there are other rubber restorers out there. When they go hard it can cause some motor noise to get into the replay via vibration

fuse said…
Wonderful guide! Thank you for the well-documented and easily-understood writing and photos.

I have a CEC BD-2000 turntable, which is virtually identical to your Pioneer model. There is almost no info on the CEC, so your guide was invaluable - I couldn't figure out how to get inside!

If you are interested, I describe my adding plasticine underneath the platter, chassis and plinth, to dampen resonances and add mass. It is on Audiokarma, here: http://audiokarma.org/forums/index.php?threads/how-to-guide-for-pl-12d-cec-bd-2000-realistic-lab-300-etc.818063/

Thanks again!
Mr Ives said…
Hi Fuse, thank you for your kind comments. CEC do seem to be the source of many Japanese turntables, just as Jelco made many tonearms for other brands, so it does not surprise me that the CEC and PL12D are virtually identical. Buying a CEC unit maybe a smart way too of getting a pedigree Japanese deck, with a less familiar name and hence cheaper price.

Your platter damping is intriguing. I think one problem with this type of deck is the high torque motor, which was fitted I presume to provide very fast time-to-speed. If it starts to drift with age, for example due to bearing wear, any speed fluctuations can get passed to the platter. Other turntables, for example Thorens , used a less powerful motor and a heavier platter, such that the platter acted as a stabilising fly-wheel

Ultimately if you get s stable and accurate result with a strobe disk, it sounds good, and its reversible too, and cheap, its worth doing
Unknown said…
Is it worth it to have bearings replaced? Have inner groove distortion that I know is not related to alignment or anything like that, distortion starts about halfway through record. I have in and out play on tonearm as well as the side to side roll of tonearm. Does this sound like i just need to tighten a bit or replace all bearings? Tonearm moves freely with just a tiny blow of air. Thanks for your time.
ndrewwb said…
I've just done a restoration on one I bought and now I've had to order a thakker belt as the one I bought was generic and causes the platter to spin at 0.7 rpm faster on each speed. Motor and spindle have been oiled, pulley and platter cleaned but still 34rpm and 45.7, what a shame.
Mr Ives said…
Unknown, deepest apologies, blogger seems to have stopped sending me notifications, so sorry for the tardy reply.

I think sloppy bearings are not going to help IGD, which even the best decks can suffer with especially with long playing time LP's (Golden Hour PYE, K-tel etc)

Replacing the bearings may be unnecessary, did you try my method of addressing the collar underneath (see pics in the blog) this should address the in/out play, but dont over tighten. Twist play is addressed by very gently tightening the locking screws either side of the arm. Itd try the one beneath first , it's much easier
Mr Ives said…
ndrewwb - it's amazing isn't it, that the tiniest change in belt thickness has an effect ? A friend who is a seasoned audiophile refused to believe that the belt thickness had any effect, but its all about ratios and the thicker belt increases the effective diameter of both pulley and sub-platter by a tiny but measurable & audible amount. I hope the thakker belt gets you back to 33 & 1/3 and 45
Unknown said…
well the thakker belt did help quite a lot, but against everyones advice i used a 3 in 1 oil and that's causing a little issue now which makes it around 33.7rpm, i'm about to redo the oil on the motor and bearings and i suspect i'll get a perfect speed once it's done. also, i dont think i saw it mentioned on this blog, but did you ever have a problem with a bouncy tone arm? i'm experiencing it at the moment and i've seen it reported elsewhere, but not much is known about fixing it.
Mr Ives said…
Hi ndreww,

how are you measuring the speed ? I am not convinced by the mobile phone apps, preferring using a printable strobe disc as described.

if the deck still measures too fast, it must be either the belt thickness, OR the belt position on the motor pulley. If the belt doesn't sit 100% on the 33 (narrow) section, and starts to creep up the taper to 45, it will run a bit fast too.

3 in 1 contains additives, its not pure oil, so probably a good idea to clean and use something else. gearbox oil or sewing machine oil are recommended, the latter also for the motor.

not sure what you mean by bouncy arm ? if the deck is too bouncy and the deck sjips with even a slight movement i.e walking across the room, its because the foam rubber cores in the springs have rotted. Easy fixed, described in the article.

Is it the cueing lever not damping the descent of the arm ? it's a case of replacing the silicon oil inside the tiny piston on the cueing lever. a small grub screw releases it.
Unknown said…
Fabulous and instructive article a real boon to a 1st time Pioneer owner like myself.
You deserve an Oscar sir!
Stephen Wilcock,
Needham Market Suffolk, UK.

Presently have-
Pioneer PL-15R
Denon DP-30L
Thorens TD150 II
AR EB101
Goldring Lenco GL78
Garrard SB86
Connoisseur BD2


Unknown said…
I used 3 different methods to measure the speed, first i tried printing a strobe disc but all the lights I have are LED now, so scrap that. I used the turntable app for a general idea, though I know it's not completely accurate, and most importantly, I play tested with my favourite albums, made recordings and adjusted their pitch in audacity by -2% which made them sound perfect.

After typing my previous comment, I went and redid both the motor and spindle oil with some proper sewing machine oil. I hadn't used the turntable for a few days after using the 3 in 1, so when I started it up earlier today it was making a sticky sounding noise, around 6 drops of sewing machine oil has since made that noise go away, the spindle bearing making no noise whatsoever (I suspect someone serviced it around 10-ish years ago, as that ball is like new but the platter belt it came with was good as gone), and after that it came to my attention that the belt was being caught on the speed adjustment fork, both ends were parallel so to me that meant that the rubber mounts for the motor had gone bad. I checked them, and of course they were. They're causing the whole motor to sit a bit lower, and in effect the spindle was too. I don't have the money at the moment to go buying new ones, or any rubber conditioner so I soaked them in hot water for a bit and that brought back their original colour, though they're still as hard as before. I decided to use some small metal washers to force the motor to a higher position, which has positioned the pulley in the right place. I know it's really bad for vibration-proofing but I can't hear it too badly at the moment and it's only temporary. Now that I've checked the speed again, 33.3rpm is coming up as around 34rpm and 45rpm coming up as around 45.6 rpm. I think that points towards the motor. I don't know if it's because of bad power (I've tried directly from outlets but nothing changed) or if the motor needs to be stripped down, but I'm completely at a loss for what's happening with it.

As for the tone arm bounce, it's not an issue with the suspension, I've cut up a kitchen sponge and that did nicely for replacing the foam in the springs. The cueing lever does dampen the descent of the arm, but it's when you use the switch to bring it back up, it will wobble up and down for a couple of seconds, and sometimes even bounces back into the grooves for a split second or so. Also the dampened lowering of the tone arm seems to shift the whole arm towards the right a little though I think that might be down to the anti skating and inaccurate scales on the counter weight. I think it might be a lubrication issue that was ignored by whoever previously serviced this. For now I'm going to have to just try my best to ignore the speed difference and hope I can afford a new motor down the line. Thanks for making this page though, it is the most detailed and in-depth guide on the internet to servicing one of these beautiful machines.
Mr Ives said…
Thank you Stephen Wilcock for your kind words ,

wow that's quite a collection of classic decks. I grew up with a Thorens TD150 Mk II as my father had one , and we used that from the early 70's until he got a 160 around 1980. probably my favourite deck.

I have to confess that the PL12D in this blog was was passed on to a friend, though I have another in my loft. I also have an AR XA77 which I need to restore, its fine other than frayed wiring inside the tonearm, which is a very fiddly thing to fix. A few decks have passed through my hands since inc a Lenco GL75 and Thorens TD280, before settling 2 years ago on my current Thorens TD321.

Which is your favourite ?
Mr Ives said…
Hi ndreww, sorry you're still having problems.

I'd guess that replacing the thicker 3-in-1 oil with thinner oil would decrease any drag a tad and you'd expect the deck to spin even faster , which seems to be the case. I'd always clean out the old oil first from the main bearing, you cannot do that with the motor, but I figure you can slowly flush through the thinner oil.

However I guess you could try a thicker oil to see if that got the speed back ? I even used Moly grease at one time.

I keep one filament bulb for strobe work, I think also the Fluorescent low energy bulbs (before LED) will pulse at 50hz and work ?

fitting washer shims seems a good idea, Cant see it's going to make any difference to vibration. I guess you could fit plumbing rubber washers on the 3 suspended bolts as shims and decouplers. of course the other approach is to slacken the grub screw on the motor pulley and raise it up a bit.

If the belt is at on the pulley ok and the belt is the thinnest available (Thakker) I'm not sure what more you can do, but I wouldn't expect motor wear to make the deck run consistently fast. More likely it would cause irregular speed or wow. The strobe disc is good for checking this, and wow is worse than too fast as it is immediately obvious. I think there is a trade off with these decks. Huge AC motors do have plenty of torque and get up to speed fast, but if they start to wear, they transmit that speed fluctuation very effectively to the platter. Thorens used low voltage AC motors with much less torque. Slower startup but I think the heavier platter had more of a flywheel effect.

The arm bounce seems like its not damping on the raise side of the piston, so you get a slow drop but an abrupt rise. I also think its worth wiping the rim of the arm rubber raise bar to get a bit more grip on it
Unknown said…
I'm going to try and flush anything left inside first with the sewing machine oil then try the 3 in 1 again. Would it be better to leave the motor turned off while it's being oiled so the oil doesn't get thrown around or would I be talking nonsense? by the way thank you so much for taking some time out of your day to help a stranger online, things like that restore my faith in humanity :)
Mr Ives said…
No Problem, want to get this one running .

Are you talking about the main bearing or the motor ?

I'd be inclined to remove the platter and spindle and clean out the main bearing with a cloth , and some alcohol, ditton the ball, get it all clean and dry and re-oil. 3-in-1 is not great as it has all kinds of stuff in it for penetration rusty joints. I'd maybe look at SAE 20W motor oil, chainsaw oil or gearbox oil, but choose one with no detergents (Castrol has additives like this)

The motor just takes a drop of so through the hole on top, but not too much. Doesnt matter if it is running, as long as none gets on the belt. I think the oil drops down into a trough that leads to a felt bearing collar at the top which soaks up the oil
Unknown said…
I hope these comments don't notify your emails or anything, I'd hate to be woken up by my phone. Sorry if this is the case, I'll stop commenting for the day.

I've just come to the discovery that my 45rpm now sounds spot on, even though my turntable app and strobe disc disagree. I never properly play tested the 45 setting, but 2 of my Beatles 45s, songs in which my opinion are really easy to hear speed variances (I am the Walrus & Strawberry Fields Forever) both sound correct, whilst on an original pressing of their 1967-1970 compilation album the speed difference is noticeable. Could this come from the fact that the motor adding 0.5rpm to a song meant to be played at 45 be less of an increase in overall speed than one meant to be played at 33?

Also, when I was referring to redoing the oil, I was talking about the motor, as the spindle is completely silent and makes no noise whatsoever, when unhooking the belt and spinning the platter is spins freely almost infinitely.

Currently I'm wondering, say my general assumption is correct and the motor is just spinning too fast, it would be spinning at a certain percentage faster on both RPM settings, and not just adding 0.5rpm to each one would it? The thought of that is sort of encouraging as I think there's something else up instead of just a bad motor. I'll try get a hold of some different oil, thicker than sewing machine but not as bad as 3 in one and I'll see what that does to the motor. You've been a great help and I can't thank you enough.
Mr Ives said…
OK, well be sure the motor is not flooded with oil. Theoretically any excess will backup and run down the outside of the motor. if you look inside is there any overspill. Maybe wipe off any from the casing or the base beneath

I dont believe the motor can spin too fast. its an AC synchronous motor and its speed is set by the mains frequency, which is 50hz in the UK and Europe and 60hz in the US. While there can be minor fluctuations in mains frequency, it is minor and not all day, but I'm speaking for the UK. They have to average 50Hz over a 24 hour period. and have very strict tolerances.

So if its not the motor it can only be geometry or rather the ratio of the effective spindle to platter ratio.

You are sure that, at 33 setting the belt sits entirely in the 33 section of the motor pulley. There is a slight fattening within this section, referred to as the crow and the belt should straddle it. Its hard to see with a one piece platter. On some decks where the platter is in two parts, its possible to remove and flip the outer platter, then you can see how its sitting very clearly from the side. Here you have to watch through the rotating platter holes .

So a printed strobe disc, like the one from vinyl engine, shows clockwise movement of the dots 33 1/3 dots on the Frequency for your country ?

BTW where are you ?
Unknown said…
I'm in the UK, the sticker on the back of the TT says 50Hz and it's obviously a 50Hz mains. I tried printing another strobe disc off of vinyl engine, cut it out and mounted it centered on an old scratched lp with an old Philips bulb from around 2009, but the strobe disc is completely blurred when rotating. If I look really closely, I can sort of make out some lines that are slowly spinning clockwise, I assume this is the effect if it's spinning too fast. While 45s sound fine to my ear, the strobe disc showed it was still a slight bit fast, backed up by the turntable app. I have looked under the platter mat at the pulley when it's set to 33 and it seems to wrap around completely fine, and moving it up and down the 33 section of the shaft in any way doesn't seem to vary the speed at all. I haven't checked for any oil overspill at the moment, I'll have to do that later but it's really confusing me what's causing this problem.

It's also come to mind that when I was removing the rubber mounts last week, the one at the back left had a smaller washer already mounted to it, like someone has had this problem before. I still have the washer so I might try to mount it back with the other 3 and see if that can help at all.

I've taken a photo of the pulley: https://imgur.com/a/hoW4GuV
The image is making me think that the washers might not be enough to keep the motor in the right spot, and instead I might be better off trying to restore the original rubber mounts.
Mr Ives said…
Hi, i have a can of platanclene, if you like, send me the mounts and ill carry out
the process described in the blog. Im jonathan Ives and my email domain is gmail.com
Unknown said…
I decided to order a new set of 1/8" ball bearings incase the old bearing (however new it may have appeared) was causing any issues, but that did not change things. I looked through my dads garage and manged to find a can of "Car Pride Tyre Black" which is essentially a rubber restorer. It did a very nice job on all the rubber parts, but still spins too fast. I also adjusted the spindle, slightly raising it and now the belt rests perfectly on the spindle. I can only conclude that I'll have to strip down the motor at some point. Thanks very much for the suggestions though, once this is finished this will be amazing.
Unknown said…
I was having a look at replacement motors on ebay, since I can solder but not very well and it looks like I'd struggle putting it back together, also the fact that I'm very lazy discouraged me from taking it apart. When looking for a PL-12D motor on ebay, you can find listings for the MK1 and MK2, it's come to my attention that the motor in my MK1 looks exactly like the ones in the listings for a MK2 motor, having green text printed on the sides, the sides being of a more brass like colour than silver, and the (what I am assuming are) coils being fully yellow instead of being yellow on the edges and white on the inside, this makes me think it's a motor from a MK2. I know that sounds like a really silly description but looking at pictures of both, my motor doesn't look the same as yours, and instead similar to the MK2 motors that sell online. I've heard that the MK2 motor had slightly different specs, since the design was slightly changed with different wow and flutter figures, and possibly a different spindle to platter ratio. Do you think this could cause the problem I'm having, being mounted in the wrong model?
Unknown said…
I quickly opened the TT to get the motors model number which was "KXM-015-D" which turns out to be the motor used in the PL-12D MK2 and the PL-15D which is different to the KXM-024-A motor which the PL-12D uses. What is this motor doing in here I wonder? Maybe someone with a junked PL-15D needed some parts to refurb this at some point, but I'm getting a new, proper motor as soon as possible, having a look at the solder joints on the power board they don't look like they've been solid for 40 years.
Mr Ives said…
Hi ndreww, interesting.

removing the motor is not that hard. I found it easiest to desolder the tabs at the circuit board end for the mains wires (see pics) as the solder joint where the wires meet the tabs are very solid.

Stripping and cleaning the motor is comparatively easy but reassembling it correctly is very fiddly. I've seen a video on youtube of a guy stripping an old RCA motor, and when he reassembles it he keeps the bolts slightly loose and taps the outside at 3 positions around the outside with a wooden mallet, and voila, its perfectly aligned. So I'd avoid that if you can

Interesting bit of detective work, maybe in the past someone has done something here, because I dont see how the standard motors can run faster than designed, given a steady 50Hz mains. Logic would suggest that the motors and pulleys would be the same, but who knows ?

Keep us posted how you get on
Unknown said…
I seem to be leaving an endless amount of comments here, but it also came to my attention that after leaving my previous comment, that the PL-12D and it's MK2 variant have different platters, which could cause a speed variance if they're even slightly different in dimensions. Now I could replace the platter instead of the motor but I'd rather just have a new motor and be done with it. It was definitely messed with before, as there was a new (ish) bearing installed, no black build-up anywhere like in the pictures, just some oil that had gone a little bit green. I can't see why somebody would replace the motor for one that's obviously different, but oh well. I'll be contacting some ebay sellers soon to see if I can send this motor in for any sort of discount on a proper MK1 replacement.
Mr Ives said…
no problem ndreww, I think its good to leave a record so others with similar problems can benefit, though my email address is hidden a few posts above if you prefer
JP said…
Hi and thanks for the excellent guide :-)
I have had a small accident with the Platenclene. Instead of renewing the rubber mat it dissolved the thin parts of it within a few minutes. The product is precisely the same bottle as in the pictures and the mat was an original but maybe some really old mats are incompatible with the Platenclene. Think I will throw a leather mat on it instead.

Do you have any experience in using Super Lube PTFE lubricants instead of mineral oils in the bearing and the motor?

Best regards//Jens
Mr Ives said…
Hi JP, I'm sorry to hear you had a bad experience with platanclene. I've used it a lot and not had any problems. with mats I spray 2-3 "squirts" onto the mat then wipe round with a cloth until everything is an even, original colour. I've used it on mats from thorens, pioneer, Nad and this weekend , Harmon Kardon and never had a problem with it dissolving the mat. It clearly does remove some surface material. Did you soak it in the liquid for a long time ?

I tend to use oils that are simpler i.e SAE20 engine oil, gearbox oil or sewing machine oil. I have since learnt that some bearings used sintered brass which absorbs oil into microscopic cavities in the metal. I'd be concerned if additives prevented this in some way. Keep it simple is my philosophy here.
JP said…
Hi Mr Ives and thanks for the reply. The mat was only wiped with a cloth after a fair amount of cleaner had been sprayed on. Dissolved is probably not the right word. It kinda made it swell and look like an indian Naan bread and it felt like it would easily rip or break apart. But after considering it to be lost I left it outside on a table in the cold and today it has almost completely recovered and regained its normal shape and thickness. Only a tiny bit of the thin parts stil has a slightly uneven surface. I have never experienced anything like this and I have used platanclene a lot at work to restore many kinds of rollers and rubber parts. None of which have ever been as old as this mat though.
Because of the experience I used LaCrosse rubber refresher for the other rubber parts and the dampers from the motor now look like they did in 1975 :-)

Excellent advice with the oil. That probably explains why I have never had any success using Super Lube with the brass bearings on my italian bike.

At the moment all bigger parts of my PL-12D are spread across the dinner table - family is not amused, but I enjoy fixing and restoring it.
Mr Ives said…
Thanks JP for the update, a matt swelling like a Naan bread (sudden mental image of the Family Naans popular in Restaurants in Sparkbrook - size of a sleeping bag) is something I've not used, but I do use it quite sparingly. It does cause some swelling when I used it contained in a bag to treat the rubber mounts favoured by 70's Japanese decks,to decouple the motors.

i tell my family sometimes I just need the uncluttered free space of the dining table. Good luck getting it all back together.
JP said…
Hi again Mr Ives :-)
I've just realized that the plinth is covered in some cheap fake wood made of vinyl. Do you have any experiences in replacing that with something more genuine like veneer or perhaps just airbrushing it?

My older sister had one of these for decades but it must have been a "mk 1" as it was real wood.

Br/Jens
Mr Ives said…
Hi JP,

My PL12D's have all been vinyl wrapped chipboard, and to be honest it looked OK to me. I have seen examples of people re-veneering decks where the vinyl has come away. on the vinyl engine forum there was a beautiful rebuild and re-veneer of a trio KD-1033, a very similar deck to the PL12D. I wonder if it's easier to build a second plinth from solid wood and migrate the deck across, keeping the original if you decide to sell it ?


BTW I'm going to write a new turntable rebuild blog on a Harmon Kardon T40 which I recently acquired. it was running fast. I cleaned the motor spindle which still had a small amount of melted belt on it. Initially I ran the motor and pressed a isopropyl alcohol soaked rag against it, later a green plastic scouring pad, till the motor pulley was clean and shiny. Speed dropped back to perfect, but I assume you tried similar with your fast PL12
Dino said…
Hi,
I have the PL-12D since 1972 and stopped using it 8 years ago during the CD popularity. Now that vynil is back took it out to play my old records and found that the left channel was not playing. I replaced the turntable belt and bought a new N75ED-2 but still no luck The right channel plays well but not the left ie no stereo output. Not wanting to dismantle to find the cause yet, can you please advise what to do?
Mr Ives said…
Hi Dino,

A few things to check. if you swap the wires at the amplifier , I assume the non-working channel swaps also. This way we can rule out a problem with the amplifier.

the wiring on these decks is pretty good quality. I would try cleaning the plugs on the ends of the red and white signal wires, they can become tarnished. A wipe with some Isopropyl solvent will clean them up.

Next focus on the headshell. The cartridge is connected to the headshell plugh with 4 small wires. Check they are all present and if you use some tweezers, check they have a tight connection both at the cartridge pins and at the headshell pins.

Finally, if you remove the headshell from the arm, you will see it has 4 small gold studs on the back which connect with 4 spring loaded caps inside the collar of the arm tube. these spring loaded caps can become stuck in and you loose a connection. I'd use a wooden cocktail stick or toothpick to work each of the 4 contacts inside , possible squirt in a very small amount of a switch contact cleaner like Servisol (EU) or DeOx( USA) and further work the little pins in.

A problem with the pins in the collar can sometimes be confirmed bey carefully removing the small rubber washer from the connector at the back of the headshell and reconnecting. This allows for a tighter connection and may bring the missing channel back
Unknown said…
Hi mate, me again. I decided to give it a month before going any further to see if I could just adapt to the way things are with my PL-12D at the moment, and I got along alright but I've spent a little more in hopes i can get this thing in a better shape. I used 2 different kinds of moly grease on the spindle hoping to introduce some drag but it doesn't seem to have done anything to help slow the speed. I saw a suggestion somewhere online to check the capacitor on the power board, but this wouldn't make sense since the motor is based off of frequency. I'm wondering if it's just the mains frequency in my part of the country that causes this issue, though I haven't noticed any variance in speed at all when the mains frequency supposedly changes throughout the day. Also ordered a can of platenclene for the rubber parts since the tyre restorers effects didn't last long and some 300,000 cst silicon oil to dampen the tone arm's decent. Overall I've spent way much more on this TT than I should have but it'll be nice to have a PL-12D that's pretty much been fully serviced at this point. Just a bummer I couldn't fix the speed.
Mr Ives said…
Sorry to hear, all that I can think left, is to show the motor pulley a bit of gentle abrasion
Unknown said…
and so I've done just that with some sandpaper. Haven't done it with a strobe disc but by ear to Strawberry Fields Forever as the mellotron seems to be the most speed-sensetive instrument I have ever heard. Good thing I bought that other motor as I now have a backup spindle incase I want to revert it. The finish on the pulley is a bit rough now, I have no knowledge of metalwork at all so I don't know if that would cause any extra wear to the belt (It sounds completely fine by the way no warbling or any wow/flutter with the pulley this way) so it seems that the only working solution was the one I procrastinated doing until the very end. All I need to do now is use the platenclene on the rubbers and sort out the tone arm's dampening and this'll be my turntable forever hopefully. Your post here has been so very helpful and your advice has been nothing but great and I can't really express how grateful I am for your replies. To think I was having regrets leaving my old AT-LP60 behind some few weeks ago...
Mr Ives said…
I cannot account for why your deck was fast, as it should be about geometry and gear ratios, a synchronous motor is fixed to the mains. Did you gently hold the paper against the spinning pulley, might be a good idea to vacuum around in case any brass filings are anywhere they shouldn't be. Otherwise - sorted. My pleasure, and as someone once said "Keep 'em spinning"
Unknown said…
I held the sandpaper against the pulley, moving it up and down to get it evenly cut down. Picked some of the brass filings up with my fingertip but it's not properly back together yet (I'm busy enjoying my music with my new pre-amp and headphones at the moment) but I'll be sure to remove those little conductive monsters before this all goes back together, bearing in mind I still have the rubbers to properly sort out before I can call this done. The royal mail are obviously really stressed at the moment with it being Christmas so that platenclene won't be here for a few days. Pairing my Shure M75-6S with a Behringer PP400 has to be one of the best ideas I have ever had, I'm so impressed with the sound quality, considering how cheaply they can be had.
Michael Larsen said…
Why was there also only 3 rubber O rings as there is on my turntable?

I found 25mm, 1 mm thick rubber O rings that leveled out my turntable, they are just not the right size, wheer can i get 4 that has more the same size as the original O rings?
Mr Ives said…
Hi Michael, I dont know why either, but if you look one of the four springs is slightly different than the other three ? I reckon anything could be used as a spacer, washers, coins or discs of rubber. If you have a punctured bucycle inner tube you could cut discs from that. Pluming washers come in many sizes too
Unknown said…
Hello Mr Ives,

Excellent Blog! So very informative and clearly explained. I have one of these decks that I am looking to replace the interconnects and ground cable on (quite a loud hum that worsens when moving the cables) but now I have all the information I need to give it a full service... without stripping down the motor maybe!

I also have a Grenadier Hacker if ever you fancy giving that a service as a side project?

Thanks again
Paul
Mr Ives said…
Thanks Paul, glad its useful. Re. Hum , it can have multiple causes, though the provided cables I have found to be good quality.
Has someone fitted a mains/safety earth to the deck ? Check the internal wiring.
Other causes can be mechanical vibration from hardened motor mounts, and unshielded cartridges like Grado.
If you’re really unlucky you get all 3.

BTW there is a very friendly facebook group dedicated to the PL12 and earthing has been discussed there too
Paul Findlay said…
Thanks for your reply.

I'll check the internal wiring and get back to you. If I do need to replace the phono cables I read somewhere that having low capacitance cables are needed, do you have any advice on that?

Thanks
Paul
Mr Ives said…
Hi Paul,

Yes. Moving Magnet Cartridges will have different sonic characteristics, based on the capacitive loading of the preamplifier, which includes the capacitance of the cable. It's generally considered a good idea to keep the cable capacitance low (<150 pF) but it depends a bit on the cartridge. Shure for one, favour a higher capacitance.

have a look at the wiring. It might well be fine, look for signs of damage or if the wires have been folded back or squashed. I think the standard cables are fine, but it could be the phone connectors are damaged, so perhaps just re-solder new plugs.

Another approach is to buy some interconnects, cut the plugs off one end, strip them and solder these inside the deck. I'm highly sceptical about audiophile cables, which I consider largely to be a scam,. In the past I've used Van Damme Microphone cables, which is widely used in the music business or Beldan R58 coax. Not worth spending more than £20/$20, and only if you have to.
DRSipes said…
Hello everyone

Mr Ives, your initial description has emboldened me to attempt the overhaul of my PL-12D-II purchased by me new in 1968 in Oregon. It has never been serviced with the exception of damping fluid, spindle oil, and motor oil. I am the original and only owner, so I know its history, and that it has been only lightly used, but never "stored away", always connected to my stereo setup. The top metal plate has never been opened.

I think a snapshot of the TT as it was originally sold will be helpful, ie the question posed by TheDutchOwner about the springs: on mine the heavier springs are definitely on the left side. That said, I initially thought the springs were in 3 different strengths, the heaviest on the left, the medium on the right rear, and the lightest on the right front. And only one of the springs had a rubber washer under it, the right front with a circular piece of thin rubber glued to the wood where the spring inserts.

That kind of information may be helpful to people who are left wondering what modifications may have been made on their newly acquired but aged PL-12D. It is always a caveat, of course, that quality control at the factory, or other reasons, may lead to differences even among brand new units. But at 51 years old, my unit is as pristine as it's going to get.

So if you agree, I will post my finding here. It will take a while, and be quite a long post. I am incredibly impressed that this blog is still active after so many years. That longevity is a testament to the continual and increasing interest in vinyl in general and the PL-12D series as a very good starting point in particular.

What do you think?

DRSipes
Pioneer PL-12D-II fully manual turntable
Pioneer PL-A45D automatic turntable
Pioneer SX-850 receiver
Pioneer SX-1050 receiver
Pioneer CTF-9191 cassette tape deck
Mr Ives said…
Thanks DRSipes for your generous offer and I would be interested to post our pictures and description of an original example.

You may need to email it to me (jonathan DOT ives AT gmail DOT com) and I will post it as an update.

i recently worked on another PL12D which featured a much simplified electrical layout with no voltage selector (240v) and a safety earth fitted. possibly a local EU version ?

you may also be interested, there is an active Group dedicated to the PL12 on facebook, if you search for Pioneer PL12D

best wishes

Jonathan

bigbro said…
hi, i'm currently undergoing resotre w/ my pioneer PL12. Just want to ask what size of the tonearm wire do i use?
Mr Ives said…
Hi bigbro,

To answer your question, the tone arm wire should be very fine and very flexible. I have seen suitable wire sold on ebay as Litz type. However are you really sure the wire in the tonearm needs changing ? I ask because its a very fiddly job, I've done it on other decks. the pioneer tonearm shouldn't wear the cable out, unless it has rubbed against a rough or sharp point in the arm when the tonearm is moving in one of the two planes.

If it's because you have hum or lost a channel they I'd explore other areas first , like the headshell pins in the connecting collar , for example, they are spring loaded and get sticky. Work them with contact cleaner and a cocktail stick or tooth pick.

Changing the tonearm wire for is unnecessary unless damaged, ditto the interconnect cables, which are good quality only slightly let down by an RCA plug which tends to get a bit loose due to the thin 'petals' of the outer section

bigbro said…
Hi mr ives, thanks for the quick reply. I was just thinking of having an emergency kit if ever coz i want to restore my pl-12 & i might destroy it in the process. Well, you said that it's a bit difficult to that effect repairing the tone arm wire, then i'll take extra care in my repair
bigbro said…
Hi mr ives, thanks for the quick reply. I was just thinking of having an emergency kit if ever coz i want to restore my pl-12 & i might destroy it in the process. Well, you said that it's a bit difficult to that effect repairing the tone arm wire, then i'll take extra care in my repair
Unknown said…
Hi
my son has just purchased a PL12D turntable and it is running slow.
my question is, should the centre locating pin actually turn or is it fixed?
alan
Mr Ives said…
The centre spindle should turn smoothly and freely. If not the main bearing is in need of a service, which is covered in the blog above . Probably the old lubricant has turned hard. Quite easy to fix
ash said…
A very helpful post, thank you. Mine kept humming after cleaning, lubrication, reviving the rubber and checking all the internal earthing/ ground connections looked clean. It turned out the issue was the earth pin on the mains plug was carrying some muck/ oxidation. Removing the pin, cleaning with wire wool, and re-wiring the plug removed the final hum for me... Bit of a "D'Oh!" moment.
Patrickblue said…
Hi Mr Ives
Firstly, well done on a brilliant blog.

Can you tell me what oil you recommend for the centre spindle bearing. The reason I ask is because of a comment left by Rainer a few years back, where he (or she) says that sewing machine oil should not be used unless the bearing has extremely close tolerances (which he/she says the PL12D doesn't) and goes on to say that a sae30 oil or even a gear oil should be used. Then in a later comment Rainer states that his/her PL12D spindle has the closest tolerance he/she has ever come across.
I would agree with the second statement, and use sewing machine oil in my PL12D.
I didn't see a reply by you, but some of the earlier comments seem to have got out of sequence

On another note, I've always thought the PL12D is somewhat underrated, being dismissed as entry level or budget, so when I removed my 3009 improved for maintenance from the Thorens it's fitted to, I thought I'd give the Shure V15 111 that normally lives in it a try in the Pioneer.
Now, according to perceived wisdom, this should not have worked at all, it being generally stated that the arm has too much mass for the cartridge, but there it is tracking perfectly at 1 gram, and sounding beautiful.
This is fitted with a Thacker elliptical stylus, which I believe is a Jico.
Mr Ives said…
Hi Patrickblue and thank you for your kind words, yes the comments do get a bit confused, I never expected to have to manage so many :)

I reckon either sewing machine oil or SAE 30, Turbine or gear box would all work well regardless. I think that modern engine oils should be avoided as they typically contain all kinds of additives designed for the high temperatures in an engine, rather than a comparatively slow moving turntable. The original PL12D user guide is not specific about the type of oil, the deck shipped with a small oil bottle intended for both the main and motor bearings, and I'm pretty sure it was sewing machine oil.

For my range of turntables I have a bottle of SAE20W/50 motor oil, designed for vintage cars. Some decks I work on use sintered bearings and I prefer to avoid modern high performance oils for the reasons above, and also getting the oil out of the pores in the bearings would be harder .

There is a recent follow up blog post on the "PL12D revisited" on the blog, you might find that interesting. It was written by Dirk Sipes , covers oils and also the choice of ball bearing
Unknown said…
Hi Mr Ives,
Great blog! My PL 12D sometimes starts having a fluctuating pitch, the music gets faster & slower, any suggestions? I tried changing the belt but it was the same.
Thanks Kev
Mr Ives said…
Hi Kev, thanks for the the feedback.

Fluctuating speed can be one of a number of things, but remember these decks are 40 years old and do need a bit of a service .
It could be :

1) Main bearing dry or old lubricant going sticky

2) Motor pulley loose or at the wrong height

3) Motor pulley mounts hardened

4) Motor bearings need oil

5) Deck springs need foam replacing.

So following the blog and performing the service will address all of these and is not especially hard to do. My first question is , if you slip the belt off the motor pulley and spin the platter by hand and leave it, it should spinn silently for several minutes until it finally stops. If its a few seconds, then the main bearing needs a clean and relubrication.

It is possible that the motor has a problem. These can be purchased on ebay and replaced, but I'd exhaust the other options first>

There is also a facebook group dedicated to repairing PL12D, which you may find useful too

So does the platter spin easily without the belt attached after a manula spin
Scottj said…
Hello Mr Ives,
No question from me, just a thank you.
Way back in 1975 my father purchased a Pioneer PL-12E turntable, which he, and I, used intermittently over the next 15 – 20 years.
It somehow ended up at my place some 20 years ago, after my parents had yet another house move. It has, since then, been sitting on the top shelf in the wardrobe, along with the amplifier, tape deck, and speakers, taking up much needed space.
The plan had always been for it all to be set up, but, lack of time / motivation, as well as not really knowing where it should go, kind of got in the way of actually doing something about it.
That was until a bit over a week ago, when it was all dusted off and I managed to work out which cable went where.
I had a vague recollection that the tape deck had an issue, and I duly discovered that that was in fact the case. I’m not terribly concerned about that, and perhaps at some point I may get the urge to see if something can be done about it.
As far as the turntable is concerned, I quickly discovered that it too had some issues.
Long story short, the belt, perhaps not surprisingly after all these years, needed replacing. This was done a few days later, and while it did result in the turntable actually turning, the actual turning speed was a problem.
As my wife said, it sounded like Jon Bon Jovi was stoned while he was singing Living on a Prayer.
Much Googling was then undertaken, along with a few more attempts at rectifying the problem, before I somehow ended up here.
Your explanations, along with the photos, made it all so easy, and I soon found myself peering under the deck of a 45 year old record player.
The shaft was duly removed, ball bearing found, and all moving parts; of which when I first started setting the whole thing up, I didn’t actually know that they should in fact move; were lubricated.
Everything was put back, fortunately with no pieces left over, and all of a sudden the platter, with belt yet to be attached, could almost spin on its own with not much more than a slight breeze.
With anticipation building, it was plugged back in.
And the result of my tinkering from your excellent instructions?
Jon Bon Jovi now sounds like he’s supposed to sound.
To say I’m happy is an understatement; I am absolutely rapt. It’s brought back a lot of memories, and Dad is now even looking forward to hearing his old record player again, that he hasn’t heard for well over 20 years.
So once again, thank you so much for your excellent blog!
Regards,
Scott
Mr Ives said…
Hi Scott, glad the blog was useful and thank you for sharing your wonderful story, many here are beloved decks with a history. it's probably a good idea to replace the foam in the springs at some point as this seems to always have either crumbled or ceased to work as a "shock absorber". Now you've had the "bonnet open" it should be easy. The 3rd thing is the motor mounts, a slightly trickier job, and only needs doing if you get any slight hum when a record is playing.

Well done, thank you and keep 'em spinning
Scottj said…
Yep, the foam definitely needs replacing, so that, along with a cabinet for it all to sit on, is on the list of things to be done.
The motor mounts looked okay, and I haven't noticed a hum as yet, but will certainly keep in mind.
Cheers,
Scott
Anonymous said…
very very, helpful article ,as i had one of these gathering dust i decided to carry out all of your servicing and found it gave very good results when playing . I also then went further by very carefully fine tuned the arm bearings and making a very solid mahogany base that compered to a linn sondeck base .This i think was by far the biggest improvement by far and as soon as it was played the clarity and bass really stood out. Regards Richard
Mr Ives said…
Thanks Richard for your kind words,

was that the vertical arm bearings too ? I've not had the courage to tweak those. Thanks for the suggestion about the base.I think it's important to ensure enough ventilation underneath as the motor gets very hot the standard base has a grille over a circular hole beneath the motor. Either similar or some drilled holes I think would be advisable to allow convection. There is an active facebook group dedicated to the PL12 deck, and recently there has been some discussion about the potential benefits to damping and weighting the platter. I've not tried it, but it's another line of thought
I revamped my pl12d.
I removed the motor from the deck suspension, and made a new mounting bracket and fixed on rubber grommets this to the bottom of the plinth.
Now there is no motor noise at all. I treat to a new sure m75ed, and the deck has never performed so well. No hum, no rumble, no buzz. 👍

Mr Ives said…
Hi Buster, thanks for your comment. That's interesting, so you have the motor mounted to the base of the plinth , so supported from below ? There is a facebook group dedicated to the PL12D https://www.facebook.com/groups/1800061146950818, it would be great to see how you have done this
eWalsh said…
Hey Mr. Ives! Great resource!

Just got an old PL-12D and it wasn't working. I took it apart, and cleaned it. Also took the motor apart and lubricated it. Put it all back together and it worked, except the motor runs backwards. The wiring is all correct. Any idea?
Mr Ives said…
Hi eWalsh,

That's interesting. The only two things I can think of is either the stator section is upside down or the phase capacitor has failed. Assuming the wires are unchanged

For the stator to be upside down, the wires would emerge from the top of the motor not underneath ?

The phase capacitor determines which way the motor turns, its the red orange blob near the voltage selector switch on some models or directly soldered across two tags on others. I cannot find a circuit diagram in the Pioneer service guide but I *believe* (please check) its a 0.047uF (47nF) 275Vac (X2 Class) capacitor and should be easy to source a replacement
Unknown said…
Stator was upside down... Oops. It's all good now! Played it this morning and it sounds great! Really appreciate the quick response and knowledge.
Mr Ives said…
Glad it's sorted, I've certainly done things where I though 'Doh', for example I was trying to balance the arm by just turning the black plastic ring , not the actual weight.

plus we now know how to play all those LP's with backward messages :)

Unknown said…
The Pioneer PL-12D does indeed use 3 different spring rates spread across the 4 springs.
Left Rear spring is .064" dia. wire, Left Front is the same size. Right Rear is .060" and Right Front is .048". The right front was much shorter than the other's. I just picked this TT up and it is pristine in and out but the right front of the plinth was much lower and bottomed out at the slightest touch. That's why I took it apart. I found no shim washers in any of the cavities. I will shim it level and give her a go.
Sincerely,
Aaron Shumaker
DRSipes said…
Aaron, That is VERY interesting! I had not thought about measuring the actual diameter of the wire used for the springs. Thanks, Dirk
lamongne said…
Dear Mr. Ives,

Thank you very much for those detailed posts about your PL-12D maintenance. It's been very helpful in my case so I want to share a bit about my turntable issues here so it might help others troubleshoot their own:

The PL-12D we got hasn't been in use for a couple of decades. When we first tried it, the RPM was way too slow and the whole deck was shaking. First off, we changed the strap. The speed problem seemed fixed, but the deck shaking was still occuring. The strap wasn't touching the 33/45 speed arm and the platter seemed fine on its own.

Then, I tried to oil the motor (the only oil type I had, which seemed ok according to my research on forums, was some white mineral oil that I use for an electric clipper). After ~6 drops, the platter was turning much smoother. But after a while, the deck shaking got back to it. It seemed like I needed to let the turntable roll for about 15mins so it would warm up and stop shaking. It was annoying, but I wasn't so confident about opening up de turntable to do a more complete service, so we used it as is for some time.

Until, lately, when I warmed up the thing again to stop the shaking, I let it roll for a couple hours (just forgot about it). When I got back to it, the RPM was off tracks and the shaking was even more persistent. After some more research, I found that it must have been some old dirt that warmed up in the motor bearings and caused the locking of it all.

Being in this deadend, I had no other choice to pull a full(er) service on our PL-12D. So I followed steps on how to open everything up, mostly with your post here. I replaced the shocks foam which made the whole thing much more stable.

I did disassemble the motor and bearings, but, as I don't have any soldering tools, I kept every cables in place while doing so (and of course, the AC plug wasn't connected during the whole process). A good soldering station is quite expensive, so I thought I would try without and it wasn't that big of a deal in my case. I had to be extra careful not to twist those short wiring cables, but as there is some wood support on the left side, I could let the motor sit there while I was working on it. It's not ideal, but for someone who doesn't have the necessary tools, it might be a good alternative.

So, having the two bearings apart, I cleaned them with 99% isopropyl alcohol and cotton buds. I followed pretty much your cleaning procedure at this point. I didn't have any grease so that's the only thing I couldn't do for the lower bearing (Lucky me that my lower bearing has a little hole that I can use to oil it once mounted!). The one thing that I wasn't so sure about was the position of the motor spindle. I managed to lock it with a gap around 1mm over the upper bearing frame. When everything was in place, it seemed like the strap was totally in the middle of the speed arm bracket!

And now... Everything is going great! The RPM is steady at the right speeds. No shaking, no trouble. The motor clean up and foams replacement did the trick and wasn't that big of a deal. We just have to follow your steps, take our time, everything should be fine.

That's about it. I've been very grateful for all the good infos I found here. I wanted to share a bit so some people might be encouraged to do the necessary. Going to fire it up again right now. Thanks again and keep it up!
Mr Ives said…
many thanks lamongne for your kind words and detailed description. Glad it's working well, and thank you for sharing your journey
dhad06 said…
Thx for the very competent guide.

I've been restoring a PL12 for my son-in-law, and I was having quite a lot of motorhum, and being on a tight budget (he's studying), new parts weren't an option. So first I tried boiling the bushes in a viscous mix of soap and water to soften them up (in Denmark it is called brown soap and in Sweden green soap - maybe the English term is soft soap?) When I pulled them from the deck, I thought they were soft, but it couldn't harm. It didn't help either.

I then moved on to the springs, and as you can imagine the foam was drizzling and almost gone. There were no rubber washers. Funny fact - the guy who had the deck for some 40 years, never removed the red "shipping" screws :-D, so the foam was both flat and drizzling. I made new foam cylinders and new rubber washers with a dinking die and reassembled.

Tada, the hum is now a thing of the past!

So thank you again!
Mr Ives said…
Thank you dhad06, that's very interesting. I wonder what was causing the hum. If the top plate is coupled to the plinth by the action of the shipping screws, perhaps the whole box was acting like the sound box on a guitar and causing resonance ?

Anyway I'm very glad that you are OK. Were the springs OK after 40 years of imprisonment ?
dhad06 said…
I am wondering as well. I could trace my steps back, but as I am no tech savvy, it somewhat scares me, if the hum comes back, and I cannot get rid of It again. :-D

Just to clarify - the hum might have gotten a little bit muted, when I removed the shipping screws, but not enough to notice.

The springs seem fine. The deck is kinda wobbly, but not more than the most other spring suspended decks, I have owned. But yes, it is crazy for how long time the energy in the springs has been trapped. :-)

Cheers Peter
I ended up mounting the motor on a base that I fabricated out of sheet ali.
That base is suspended on rubber bushes, fixed in turn onto the wooden plinth.
(ie, not on the deck)
so the motor vibrations have a double buffer to pass before getting into the pickup arm.
more importantly, and vibrations of the motor are coupled into the mass of the plinth, which severely damps out vibrations.
When i place the stylus on the vinyl, there is absolutely zero motor noise... Nada. :-)
My PL12 deck now is far quieter now than it was when it was new!

if you want photos, send me your email and i will oblige.
Mr Ives said…
Thanks Buster. Most interesting. Do you find that with a double decoupled motor you get increased wow ?
Mr Ives said…
BTW I'm jonathan ives and I'm on gmail
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