Sansui P-50 belt drive turntable slowed down.. any ideas (it's not the belt)? LONG.

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: Hi everyone : I have a Sansui P-50 turntable that has slowed down a bit and can't find the cause. : I must 'confess' I tried some tweaks on the unit. None of them should've caused trouble (I tried cork and felt platter mats, that kind of thing) except for one: : I played around with a glass 'platter mat' for a couple days some time ago. It didn't sound too hot so I put it away, but the turntable 's been slow since then. The belt was stretched, but changing it had no effect. : I tried a drop of oil (sewing machine oil) on the platter bearing (without disassembling it); I also let a drop slide down the motor shaft. No change. : I cleaned the surfaces the belt rides on with some alcohol (platter inner rim and motor pulley), no success either. : I tried cleaning (washing) the belt, talcing the belt, cleaning it again, no success. : Today I finally decided to tear into the unit, so I did a couple things: I disassembled the platter bearing and cleaned it of all grease and oil. : I'm not sure what to put on the bearing (I've been told everything from light oil to heavy grease) so for now I put it back again dry. The platter spins freely with some minor noise. What should I use on the bearing? : I also noticed the motor is mounted on a 'suspended' assembly of sorts, with some rubber pieces around the screws that hold it all together. This gives it some 'play', but to me it appears to be too much (it's fairly loose). : I tried affixing it a bit by using a hefty rubber band attached to the chassis screw posts to pull it back away from the platter (my 'theory' is that the belt is pulling the motor towards the platter, therefore reducing belt tension and speed). This actually slowed it down further, the tension might have been too much. : Last thing I tried was adding a rubber O-ring to one of the suspension points on the motor (there are three) so it couldn't 'bottom out' (and be pulled towards the platter). : This might've helped a bit, although by now I'm not that sure anymore. I might have looked better with a strobe disc though. It's still not perfect, in any case. : Only thing to check is the motor itself, but I don't know much about motors. It's an AC motor fed straight off the mains, BTW. Local mains frequency is the one indicated on the unit. : Can the motor have become 'tired' or need cleaning? If so, could anyone help me out? : The turntable did work fine until I started playing around with it, I used it for quite a while with no trouble whatsoever (I'm fairly sensitive to pitch changes so I'd have noticed if it had been slow before). : Only thing I've left to try is to add one more rubber O-ring to tilt the motor suspension even further, other than that I'm out of ideas. : I'll appreciate any and all comments, advice, suggestions, help, etc. : Thanks in advance, sorry about the long post : Damián

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