BSR idler noise

[ITAM805]

Hi all, got a late 60's Ferguson player with a BSR deck (unsure of the model) which has a noisy idler wheel, or rather something rubbing on it?

The noise is a scratchy rubbing sound that gets worse when the motor is turned off and the deck is running down If however I put slight pressure on the speed change selector downwards, by that I mean from say 45rpm towards the 33rpm position the noise disappears?

Any suggestion what might be happening?

[slidertogrid]

It may be the spring that tensions the wheel catching the motor spindle.
Check the grommets that are on the motor mounts if they are deteriorated the motor may have moved out of the correct position.
If you remove the turntable and operate the speed control you may be able to see what is catching.
Rich

[ITAM805]

Thanks rich. The rubbers mounts seem good and supple and the tension spring doesn't touch the spindle. With the turntable off the noise disappears!

[RojDW48]

Possibly the idler is bearing on the drive spindle between two of the speed steps? I think the stepped drive can be adjusted on its spindle on one of these.

[ITAM805]

Thanks Roj, I did adjust the screw that lines up the idler with the spindle but this makes no difference to the noise. The aforementioned speed adjust lever seems to slightly relieve the pressure on the idler, so I'm wondering if the wheel is making the noise and this is amplified by the turntable, although why it gets noisier with the motor off is a puzzle?

[john600601]

I have had this happen a lot on these C109/C154 decks, I'm sure I know the sound you are referring to, the sound of two surfaces rubbing together, though as you say why it is particularly noticeable as the deck/motor shuts off I can't work out either. Then as you say no noise if spun manually when in the stop position. It's to do with the inner rim of the turntable though as I have done a lot of swapping of idler wheels and platters to try and get to the bottom of it as at one time I had four or five on the trot all the same. It only seems to affect the plastic platters not the metal ones. What I have done seemingly succesfully is to use a black spray paint available from hobby shops and spray the inner perimeter surface, leave it overnight and that has always solved the problem without fail. In effect giving a new coat to the plastic platter. I initially thought this may wear off after time and be back to square one but it doesn't seem to be the case and they have always run quietly after that. I must have done a dozen or so over the last few years. At the same time worth cleaning/roughing up the idler wheel though this alone never solved the problem. Hope that helps.

[Andrew2]

I'm glad it's not just me. I came across this effect several times on (I think) BSR low-end decks. Only present when the t/t is in place and the deck has just switched itself off and sounds like something metallic gently scraping on the drive rim. A sort of thin, zinging sound. Never did trace it!
Please tell us what it is if you ever find it!

[Edward Huggins]

A quick test is to coat the inner platter rim with Talc to make it "grippier". If this works out, then suggest you proceed to (evenly) spray paint it as well described above.

[ITAM805]

Thanks John, I tried the paint trick you describe using some automotive matt black which has had a minimal effect on the noise, but it is quieter. Does it matter which paint type in your experience? The platter run down noise is still present. Further experiment needed ...

[john600601]

I use Humbrol Acrylic Spray Black Satin 85 (AD6085) though assume any similar would be OK including matt. If as you say it has made it quieter I'd give it another go as you may have a particularly bad example but also rough up the idler wheel at the same time with some sandpaper or similar. Two clean and fresh surfaces should give a good result or at least have with the ones I have done. This seems to be a fairly recent thing as I have been doing record players since the early 2000s and it's only the last few years I've experienced this so whether it's to do with the age of the plastic or something I don't know.

[ITAM805]

Thanks John. Just for giggles I tried sticking 20mm insulation tape on the running surface and it works well, the run down noise disappears too. Not a permanent fix alas but an interesting result nonetheless

[john600601]

Good idea, definitely proves that is where the problem lies.

[Techman]

It certainly proves that the idler is not fully disengaging.

[ITAM805]

Thanks Techman. Your comment got me thinking about my observation that slight pressure on the speed control affected the noise, so I wondered if the spring tension was too much? Now I dont see how the spring tension could have increased from factory but I relocated it from it's original position so as to lesson it slightly and the it seems to have cured the noise. The platter run down now takes longer suggesting the idler wasn't disengaging correctly as Techman says. The turntable is now as quiet as one would expect of this kind of machine

Many thanks to all

ps: the 20mm tape is still on the platter rim, dare I remove it ...

[john600601]

I'd be interested to hear what happened if you do remove it.

[Radio_Dave]

Could it be the motor's thrust washers are the wrong position? With the platter removed watch the motor spindle and see it it jumps up, when the mains is turned on and the rotor finds its position within the magnetic field.



Regards
David