JVC top loading vcr HR-7100U problem
 

I 'm wondering what i missed. when i picked this up several months ago, it wouldn't do anything due to all the belts failing. Changed all that i could find including the counter and now it plays but it won't rewind, ff, or take up the slack to eject.

I do not know that model, but it sure sounds like a bad idler/tire or similar item, or maybe a spring fell loose while you were replacing the bad belts. Does it "try" to rewind or fast-forward when you select those modes? Can you trace the mechanical actions it takes as you switch to different modes to understand how the motor rotation gets to the reels (or is not getting to them)? You would do all of this with the top off, of course. Back in the 80s and 90s, you could buy a clear-plastic "decoy" VHS cassette shell that you could insert to let you see the various mechanism parts easily as you used different controls; maybe you should try to find one of those shells.

Cool. never saw a clear decoy before. i'll have to pull the cover again and see. i'll post again when i find out.

+1 on the see-through dummy tape. It will let you see the idler slipping on most models, which is likely to be your problem.

Available here, about 3/4 the way down the page.

http://www.studiosoundelectronics.com/tools.htm

I need to get one of those. thanks for the tip!