I recently bought a second hand Pioneer pl 320 turntable. Each time i put tonearm onto record it immediatly returns to start position. Then turntable continually switches on and off with tonearm lifting up and down. Seller says it worked fine, so maybe something happened during transit. Not even sure how to open it up for repair. Any ideas anyone?

Lee, February 2009

Remove the motor assy and you will see the main nylon large gear, it had 2 metal cams under the one screw on top of it. One is the start cam and it must slide freely on top of the other one cam. Over time the grease binds up under the start cam and it doesnt move back in as the motor moves the nylon cogs around and so it start over gain and again. Degrease and lightly lube the metal cam so it moves freely by using your finger, reassemble and test.

Chris, October 2010