Pioneer sk 700 tape deck intermittent

[donahuest]

Hello. I’ve been working on this pioneer for a bit. I replaced the belts and it will play. Rewind works a little slow and ff doesn’t work. I would be happy to get it to play properly. Once the play is engaged it will play great till the tape ends. Then sometimes it will play again and sometimes the wheels shown in pictures don’t spin then it stops. I noticed that if I hit play and it doesn’t spin (I can hear it trying) and I just start the wheel in pics with my fingers to get it going it will continue to play great again unti stop is pressed. Can anybody help me where to start? It seems to play great once started , the speed is good too.
Thanks in advance.

 

[donahuest]

Here is video
https://youtu.be/pYbNjdGgAmY

 

[hopey]

These are super hard to fix due to the extra burden on the belts due to the mechanical load of the gears and cams.

You need to use belts that are tight enough to prevent slippage but still allow enough speed for the tape to sound correct

You may also have to service or replace the motor to get it enough torque to operate the gears and cams correctly

 

[donahuest]

Thanks. It seems that the problem is that the gear shown causes the head to move into place when the play button is depressed. Should I replace the square belt with a tighter one?

 

[Fatdog]

Thanks. It seems that the problem is that the gear shown causes the head to move into place when the play button is depressed. Should I replace the square belt with a tighter one?

If the belts are loose, definitely get a replacement. A belt of manufacturer's suggested length is best. If you go with a belt that is too tight, you will put extra strain on the motor.

 

[hopey]

The one I worked one had the flat belt replaced but was two tight. I replaced with a slightly bigger one then it could reach the required RPM to operate the cams.

I had to isolate record Coil as it would crash the mechanical logic (unrecoverable).

 

[fyj2972]

Old grease