[morzh]

The tray refuses to slide out unless helped. I changed the belt close to 3 years ago and lubed it without thorough cleaning the old grease; the problem resurfaced very soon (few months) after the reassembly (I had the thread here, it was a handful).

So my question is this:

I thoroughly cleaned all the points where I saw grease.
What type of grease do I use? Regular calcium, Lithium, do I use liquid for axes for nylon gears?

I have Lubriplate No 130-AA calcium grease, and i have Liquid Wrench, the Lithium Grease. I used it the first time.

The pats that were lubed are mostly plastic on plastic.

If necessary, I have pictures; if not, I opened a thread on AudioKarma.

https://audiokarma.org/forums/index.php?...e.1019506/

[RodB]

I have a tube of silicone grease for plastic on plastic.

[GarySP]

I use P B Blaster spray silicone lubricant on non-electrical points of contact. Spray nozzle goose neck lets you get into tight areas easier. Any big box or auto supply store carries it. You don't need a lot! Take care and BE HEALTHY! Gary

[morzh]

Well, after many threads on many forums, plus reading the references of the references, I see that the right choice is MOLYKOTE® EM-30L Grease, a DuPont goop, which is a PAO grease with lithium and PTFE, formulated specifically for plastics.

https://www.dupont.com/products/molykote...rease.html

I ordered a 4oz can from Amazon Friday, it will be here next week.

Of course before I found it, I bought some silicone lube spray, a tube of lithium grease in addition to what I already have.

Well, I have been patient, so I will be a bit more patient.

[TV MAN]

I've run into the same thing. I don't think the size and/or quality of the replacement belts are the best anymore. Probably NOS. They last a couple years then start slipping. I have a couple old cd players and VCRs I want to resurrect. I tried different lubes too, no avail. I'll have to try what was mentioned.

[morzh]

Tim,


No, they were not NOS. That is, in a way....they are PRB belts. Not Philips.

And changing it did improve things: the belt was slipping, and it is no longer.
Same thing happened to my old Kenwood CD changer, which along with the whole system was given to my son. No amount of lube helped; but as soon as I bought a PRB replacement, it just worked, and still does, 2 years after.

Now, I am not sure the lube will help, but a 30-year-old machine might need one anyway, so why not start from what is warranted, and then start looking at the rest? Same as with the radios: why troubleshoot the whole set without checking the tubes and replacing the know-to-fail caps, right?

My methodology of troubleshooting is: no spending time on the questions that do not even have to be asked when the maintenance and low hanging fruit problem weeding out have been performed. Works for me every single time.

So, this weekend (the lube had come 2 days before I expected, Tuesday) I will attempt the lube and assembly, and then we'll see.

[morzh]

So. I ordered and 3 days ago I received the Molykote EM30-ML, and today I went to apply it.

So, first things first, I used Kluber oil to lube the motor's mearing. Not that I think it needs it but won't hurt.

Then I applied the Molykote to:

Both axes of nylon pulley and rack-n-pinion gear cogwheel.
4x grooves in the slide which are used by the CD table to go up and down.
The nylon rollers, every one.
The inclined surfaces the Disk hub holder uses to go up and down.

Then I reassembled the player and tried the slide. No change. Same exact problem as before.

Then I lubed the pins of the Disk hub holder that are used for it to turn when going up and down.
After this I could see some improvement: the table started pulling out, but after 1/3" it would stop. I applied the lube again after extracting the holder, with the same result. Clearly this one was important as this is the only point of lube, which affected the operation at all.

At this point I removed one spring pulling it down, and the slide came out without effort.

So I ended up doing what I thought I could avoid: I stretched the outside spring a bit, and the slide started coming out after this.
Then for symmetry I did the same to the inside spring.

The CD works now after the reassembly. I could see that it is just a tad sluggish when coming out, but comes out nevertheless.

Well, it could use a lube after 30 years plus, and I think it was the right thing to do. However I should admit that the lube itself has not solved the problem.

Two possible causes:

1. The motor has lost the torque.
2. The pins of the hub holder lost their smootheness to the point where even withh the lube the friction is more than it should be.

It plays just as good as it did before.

So, this concludes my efforts.

[morzh]

Today I decided that I had in fact left one stone unturned, which is to check the driver itself, and opened up the patient again.

I decided to take a good look at the driver. I noticed that

1. There is a mistake in the sch (one of the diodes shown backwards).
2. Instead of -6V there is -5V. This lowers the driving voltage by 1V. However, upon the investigation (I actually took the board out to recreate the circuitry), I noticed the LDO that creates the -6V out of -18V, which is supposed to be UA7906, is actually MC7905, which is neg. 5V LDO. The LDO seems to be factory installed so I do not think this was a repair. Also it connects to -10V instead of -18V (which is OK).

So, I am not sure I want to change this, as i am not sure if this was the factory practice for a long time. Whatever it is, it is factory. I could possibly get an MC7906 and out it instead, but as said before.....

[morzh]

PS. And in the meantime, purely serendipitously.....look what I found. Funny. Grease for ONLY CD880.

https://www.ebay.com/itm/134231724374?mk...3931653835

Grease Bold for Philips CD 880 CD Player Compact Disc Player
Item specifics
Condition:
New: A brand-new, unused, unopened, undamaged item in its original packaging (where packaging is ...
Marke:
BlackReel
Herstellernummer:
15548.6
Produktart:
Ersatzteile, spare parts
Markenkompatibilität:
Für Philips
Modellkompatibilität:
Für Philips CD 880
Gerätetyp:
CD Player