Which oil for CDM4 mechs?

[johnm]

Hi there.

There have been a few references in the past to re-oiling the CDM4/19 (etc) mechs but nothing concrete. Someone mentioned clock oil a while back but what actually IS this? What viscocity etc?

I have a CDM4/22 in a Naim CDI which is working/tracking fine but the motor is slightly noisey now so I need to re-oil it. Can anyone recommend a suitable oil for this - something I might be able to buy easily at Halfords or similar here in the UK? Would good old 3-in-1 be OK or is this too thick for the motor?

Many thanks.

- John

[martin clark]

Whatever you do, DONT use 3-in-1. It's a heavy, low-grade base oil diluted with kerosene (for penetrating qualities) - so it eventually dries out into a sticky, gungy mess

I've heard of using a good quality synthetic oils in other motors (eg Mobil-1 - if you have some lying about already for your car)

[johnm]

Hi - many thanks for your reply. Sorry so late in replying but I haven't gotten around to dismantling my CDI yet.

So would Mobil-1 be OK for oiling the motor as well, or would I need some light grease for the thrust pad here?

Cheers,

- John

[jacco vermeulen]

If you desire something fast and easy, get a small flask of oil for oil-free air compressors and air tools.
Plenty of places where you can buy it, an automobile parts and tools shop will have it.

[martin clark]

john - I've used Mobil1 on CD motors (inc. the CDM9 in my Naim CD2) with no problem.

It only takes the merest drop, applied with a needle or similar - the stuff is thin and will creep anywhere, usually unwanted! I havent looked at teh thrust pad, but a light grease would make sense eg silicone-based - oil based ones are likely to attack the plastic.

[musicomputer]

Are you sure that it's the motor causing the noise? It's more likely to be the disc clamp.

According the service manuals I have, the only things that should be lubricated in a Philips CDM are the two ball bearings that the swing arm pivots on. The recommended lubricant for that is "silicon oil 1000cts".

Best,
Paul

[johnm]

As the CDM has been in use for about 15 years now I just assumed the motor bearing thrust pad might need lubricating now? Perhaps the transport is a little noisey compared to modern units. It's working fine at any rate.

I may just lubricate the ball bearing on the swing arm and leave it at that next time I have the machine apart for whatever reason.

Thanks for all the suggestions guys - much appreciated

- John

[tubenut]

Are you sure that it's the motor causing the noise? It's more likely to be the disc clamp.

Agreed. Clean the clamp and the ball and relube, you could use something as daft as a wee bit of petrolium jelly. If there is a little indentation in the pressure plate, sand it a little with very fine sand paper until the dent is no more.

If this has never been done on a wel used CDM4/19 I can almost guarantee a better sound afterwards too....

While you are there fill the clamp honeycomb with blue tack or similar.

[musicomputer]

Clean the clamp and the ball and relube

Also, the spring that holds the clamp shut might be a little tired after 15 years and may need replacing.

Best,
Paul

[johnm]

The mech used in my Naim CDI is - I believe - the CDM 4/22. It uses a lightweight magnetic clamp to hold the discs, not the usual disc tray type ala Phillips. It's a top loading machine.

The only two points which I believe may need attention are the laser swing arm pivot, and the motor bearing thrust pad. Reckon after 15 years of use I should give both a check and - if required - a lube.

Cheers,

- John