I've recently purchased a WM-31 just because I thought it looked neat, though cheap. After giving it a thorough clean and lubrication, the mechanism operates as good as a low budget one will. But the motor seems to be excessively loud, to me. It's not that it makes any kind of knocking or "bad" sound, it just buzzes a lot (not in the audio). The buzz is pretty much the same as in brushless motor Walkmans from the 1990s, just a heck of a lot louder. So, I'd like to ask - is this normal for this model?
Hey, I just created an account here to reply to this lol. Even though I'm 3 years too late. I have the same walkman with the same issue. Everything else is fine and it plays music without any problems. I can't believe it's supposed to be this loud so maybe this is some kind of problem these things get after all these years?
Some motors are louder than others. If both the top and bottom bearings have been properly lubricated and the buzzing noise persists, it's likely to be normal. Have seen motors that seemed particularly loud to me (a recent example is the Koss Music Box), but remained like this even after lubrication and the wow&flutter value was excellent. However, a video or audio recording would be helpful to make an assesment of "normal".
Looking at the service manual, I see this motor a slim-type and it has an integrated governor. If you can provide pics of front and back of the motor I can recommend further steps into lubricating it. As for the noise, it seems very similar to the noise WM-150 series walkmans produce: a louder noise in the beginning and then a constant hum. It might very well be normal, but lubricating can't hurt assuming it's relatively straight-forward to do. The WM-150 series are like this: https://stereo2go.com/forums/thread...-type-motor-in-sony-walkmans.7943/#post-59754 I do suspect this WM-31 might be of a similar design but with a small PCB containing the governor. For reference, this oil can be used to lubricate motors: https://www.ebay.com/itm/164185783921
Thank you for your constructive reply. Unfortunatley I'm not confident enough to take apart the motor. But what I did is I just took the walkman apart again, popped the whole main board out and lubricated all gears. This actually reduced the hum by a lot! It's not fully gone, but also not as obvious as it used to be before (it was audible even wearing headphones). It's at a level now I can live with and hope nothing gets damaged.
