Music Hall mmf-7 spins faster

I just finished my testing with a multi-meter (I couldn't locate a variac) and found between 115.6 and 116.7 volts. Better yet, I used a 500W AC automatic voltage regulator (and plugged the motor in): no change. It still spins too fast, somewhere closer to 45 rpm than 33 1/3. I really don't know what else to do. And please note that I used 2 different Music Hall motors with exactly the same results and that the Speed Box II didn't/doesn't change a thing.

I am desperate now.

One more additional bit of information. The multi-meter reads 18 volts at the motor's power adapter output.

Question: is there any kind of belt inside the motor that might be causing the problem (because it's dilated or something)?. It's definitely not the AC voltage.

Still desperate.

Lrmellon -- Are you reading the 18 volts while the motor is connected and running (in which case it is probably much too high), or when the motor is not connected to the power adapter or is not running (in which case it might be ok, and the best way to tell is to compare the measurement with your friend's table, under the same conditions)?

Re your second question, I have no knowledge of what might be inside the motor assembly, but my guess would be "no."

Regards,
-- Al

Thanks, Al.

I have that reading when the power adapter is connected, but with the motor not running. I have the same with the mmf-7.1.

I don't get what's wrong; there must be a rational explanation (and a solution), I'm sure.

Just grasping at straws here, but have you at any point taken your complete turntable to another location, such as your friend's house, and tried it there? Although it would seem unlikely, perhaps there is something grossly wrong with your ac power, either the frequency being too high, or unusually large amounts of harmonic distortion. If, as I suspect, the turntable's rotational speed is synchronized to the power line frequency, perhaps that could be the explanation.

Also, you've undoubtedly checked this, but just to be sure, could there be an accumulation of some sort of detritus around the rim of the small pulley, that would in effect increase its diameter?

Regards,
-- Al