JVC RC-646L - Auto-stop constant clicking when try to engage Play (but sometimes it works!)

[richi71]

Hello All,

I hope someone can guide me with a frustrating issue on a JVC RD-646. The deck had been working ok, belts change wasn't too bad but auto stop is now a problem. Initially the auto stop just did not work at the end of a cassette. Now the issue seems to prevent play. When you press play it will not stayed engaged and a constant clicking is heard (the solenoid activating over and over). Every so often however Play will engage and everything plays perfectly. It seems like the mechanism possibly just to catch in the right way and every few attempts it does?

I guess this rules out electronic issues and is possibly pointing to more of a mechanical issue but I'm far from sure what to adjust!! The manual gives two areas for potential adjustment. I put the relevant sections below - I hope that is ok, The adjusting arm for the pressure I can see in the mechanism (1st pic) but not sure if this is what I should be adjusting. The adjustment for the timing (2nd pic) I'm struggling to see where the stop detect level is to adjust! Again even if could find it I'm not sure it's what needed.

Please can anyone offer some assistance. I'd really like to have this deck working

 

[floyd]

The new belts could be too tight causing the auto stop to engage.
Loose belts it will not engage auto stop.
Belts too tight auto stop thinks it's at the end of the tape because off resistance.

 

[richi71]

Thanks Floyd, it had been fine with the new belts though but I went back into the box because the balance wasn't 100% and wanted to clean again the switches. The odd thing is that if I attempt to engage play, then release the play button and let it slip back before it clicks in to place, and then press it again it seems to allow the mechanism to catch properly. After that the tape plays fine and auto stop too! I was worried I may have put something out of alignment when opening up, or maybe something electronic is failing / has failed.

 

[floyd]

One thing that might help is to lubricate any pivot points and bearings and sliding assemblies .

 

[richi71]

Thanks Floyd - I'll give that a try and report back. I seem to have blown the power fuse so waiting on a replacement but hopefully will have an update in next couple of days.

 

[hopey]

It has a mechanically activation so you must have a clean pinch roller; try using 600 grit wet and dry sandpaper and then clean with alcohol.