Pioneer PL-L1000A service and repair questions

Jeff W.

Jeff W.

Yeah! Yeah! Yeah!
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I've had the good fortune to purchase one of these tables locally. I have been cleaning it and recapping it. I have replaced all the electrolytics on the power supply board and the control board. These are no problem to remove and service. Now I want to recap the board for the drive motor. I've replaced some of the capacitors that are on the perimeter with success, but have not replaced some that are more interior in location as they are tougher to reach when trying to install replacements.

It would be much easier to replace them if I removed the motor from its mounts on the base but I am worried I will disturb the alignment/geometry between the spindle axis and the arm. I have the service manual and it does not address removal or replacement of the motor assembly and any alignment issues that could arise. Does anyone have experience with this model or know if the mounting of the motor is designed to locate it precisely without adjustment?

Another challenge I am facing is the suspension. Mine came missing the springs (PBH-169) at all four corners and the "case assemblies" (PXB-185). Does any one have any springs or case assemblies? I have placed a WTB add in Barter town Parts. Does anyone know of viable substitutes for the springs? If you have the case assembly part and don't want to sell it I could get by with dimensions to make my own it someone wouldn't mind measuring them. I could even provide a "looks like" drawing where the dimensions could just be filled in. Any help or advice will be appreciated.
 
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The motor should not need adjustment since it just screws to the base - it's not an issue to remove and disassemble it. As for the springs I'd go to several good hardware stores and pick up a collection to see which work.
 
The alignment of the Hall sensors to the rotor magnet vs the trimpot settings is critical, do nothing that disturbs either if you cannot make the necessary adjustments as per the service manual.
 
Thanks for the tip Pio1980. I'm assuming this means if I remove the drive motor assembly consisting of the Rotor unit, control assembly and the base unit (PCB) as one from the turntable base I will not disturb this relationship. I just want to remove the three mounting screws that secure this motor assembly to the base so I can flip it over and access the electrolytic capacitors on the Base Unit (PCB). My concern was relocating the assembly after removal. When I go to secure it back to the base does the center of the spindle have to be in the exact x and y axis as it was previously? I would guess it does. Is there a provision(s) to locate it precisely (locating pins, for instance) in the mounting position (exactly as it was before removal) such that it's a non-issue or will I need to adjust the arm to the potential "new" x,y position of the center of the spindle once I return it to its mount?
 
Yes, indeed, thank you. I have it and printed myself a hard copy when I fist acquired the table. That is S.O.P. for me with any new piece of gear. Unfortunately, the manual gives no instruction as to drive motor servicing or replacement and its positioning in relation to the chassis or the arm.
 
I'll have to try to download the manual to my tab, the computer with all my doc's is out of service.
 
My login for TVE is on that computer, so no joy.
However, you basically have it right. Don't change anything that affects the present motor parts a!alignment if it is running properly. That includes the rotor clearance re the thrust pad bearing, and the trimpots for the Hall commutation.
 
My login for TVE is on that computer, so no joy.
However, you basically have it right. Don't change anything that affects the present motor parts alignment if it is running properly. That includes the rotor clearance re the thrust pad bearing, and the trimpots for the Hall commutation.
 
I appreciate your desire to help me find the answer. Please don't go to too much trouble. If you're curious and just want to see the manual I'd be happy to e-mail you a copy. PM (conversation) me with your address and I'll be happy to send it your way.
 
Thanx for the manual. I see nothing other than randomly changing the trimpot settings that could cause problems with the motor, as long as it goes back together exactly as it came apart. Watch out for ferrous debris on the rotor during reassembly.
The motor is very simple with just the two trimpot adjustments, everything else is preset by assembly.
 
My pleasure on the manual. Thanks for taking a look.

I've gone ahead and removed the motor assembly, but took an overhead picture of it first so I record the location of the motor as best I could. I replaced the caps I could not easily access prior to removal. When replacing the motor there is nothing that locates it precisely where it mounts with three screws. It would be hard to return it to its exact location once removed without some kind of reference marking. The photograph aided in positioning it very close to its original position, but I can't be sure it is precisely in the exact same position. However it is, at least, very close. I guess I'll find out when I go to set it up to run.

I removed tonearm lift motor and its rubber sleeve. I treated the sleeve with a rubber rejuvenator and preservative. The motor seemed a little loose in its mounting cage before removal so I added a thin sheet of rubber over the motor to shim it within the cage and hold it a little more rigidly. It's not real tight now, but it seemed too lose previously.

Cason was kind enough to supply me with suspension parts :beerchug: and I ordered "Professor Bizzt's" spring locating rings that will complete the suspension.

Now I will move on to cleaning the tonearm rails. I see that I should use a lint free cloth and Naptha. Is this still recommended?

Is it alright to remove the tonearm from the carriage? What precautions need to be taken? Can anyone point me to a thread or link that is the most comprehensive about cleaning the rails and restoration of this table in general? I've seen some threads on AK. One of the best ones seems to be missing most of the photos. Any direction is appreciated.
 
I wouldn't disassemble the arm and carriage assembly beyond what is necessary to fix a problem. Naphtha is an excellent degreaser but readily dissolves styrene plastics, so test first an inconspicuous spot if used on plastic.
The lone rear carriage rail roller is damped with silicone goo, leave that be, don't clean or lube this roller bearing! The others can be lubed, clean the rails with naphtha as you said. The rail contact part of the rollers can and should be carefully cleaned.
 
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