Sony VO-7600 tension issue?
 

Hey there.. I have a VO-7600 umatic and I have changed all the belts. I removed the carriage and have tried to play a tape and it struggles to pull the tape. I can get it to play a bit but will shut down. I noticed that the T tension regulator arm when it is threaded bounces alot. It does not do that on my other 7600. Also when I power it on it goes to stand by and the other does not. I cannot find a service manual. Anyone have any ideas? It has to be something with the reels in that area.

for the tension: see 17.30 min mark
https://www.youtube.com/watch?v=TNXLdIxw5pY

If you changed the belts with original belts it should work, if chinese cheap /thin belts i guess it's slippin' / not enough torque power ; with a more thorough cleaning maybe (old gum.) ...

The problem could be the deck. It could be the tape. It could be a combination of both.

Well its definitely not the tape. I have 2 of the same models and one plays the tape perfectly and the other does not. I think its the T tension regulator arm. It is loose. I cannot see from the service manual how to tighten that. There is an adjustment but it does not stay.