Panasonic RX-CS780 Belt Path Query

[Darkhorse89]

Hi all.
Wow, what a great forum I've stumbled on!

So my query, I have a Panasonic RX-CS780 tape mechanism, that fast forwards/reverses ok, but the play doesn't seem to want to work.
Taking it out of the unit and comparing it to other photos I've seen on here, mine doesn't seem to have the second pulley/flywheel as indicated by the red arrow.
Does this mean that it has been "lost" over time, or was it even there to begin with? Without that arrowed pulley, should there be a belt between the left pulley and the upper rubber pulley????? (badly drawn in blue)

Thanks in advance
Malc

 

[BoomboxLover48]

One way to figure out the belt path is to see if the pulleys are in the same position or in the travel plane, when all others are in place. Check double pulleys on motor pulley also if there is one like that.

I hope the pics below can help to some extent. Follow the A, B, C, E. F path...

Our experts will have more information on it.

 

[Darkhorse89]

Hmmm, judging from that diagram it looks like I’m missing the bottom right pulley. I just have the black under part of it. I must have taken it apart many years ago and put them somewhere “safe”. ‍

 

[goodman]

Yes, there is obviously some difference...
It appears that the second pulley/flywheel is missing.
It was apparently lost during previous repairs.
You will have to improvise and find and install such a pulley.
Here is the problem shown and solved:

Panasonic RX-CS780 Belt Path? Help!

www.boomboxery.com

 

[Darkhorse89]

I’ve had a full day search trying to find that bit, looking in all my “safe” places, but no joy.
Hmmm, tracking down that specific part I feel is going to be impossible.
Thank you for your help though.

 

[Superduper]

Actually it looks like that black pulley doesn’t even belong there, like someone replaced the original one with some random one. If you compare the photo of the deck in the other thread, and the diagram posted by boomboxlover, the black pulley should have holes and recesses, like the one in the other photo. Also the larger of the two wheels should be the more distant one from the motor, but on yours, it’s the closer one to the motor? So either this is a different deck design, or parts were swapped and or missing.

 

[goodman]

You can't put the belt on the left pulley (as you drew it)
because it will rest against the motor housing and the direction of rotation is reversed.
I think there is a solution to this problem:
You should try (if possible) to remove only the black pulley (without the metal base)
on the left side and put it on the right. You may need to glue it if it is loose.
Then you can put the missing belt on.

 

[Darkhorse89]

Actually it looks like that black pulley doesn’t even belong there, like someone replaced the original one with some random one. If you compare the photo of the deck in the other thread, and the diagram posted by boomboxlover, the black pulley should have holes and recesses, like the one in the other photo. Also the larger of the two wheels should be the more distant one from the motor, but on yours, it’s the closer one to the motor? So either this is a different deck design, or parts were swapped and or missing.

I think the metal top flywheel bit is missing, which has a pulley on top of that.

You should try (if possible) to remove only the black pulley (without the metal base)
on the left side and put it on the right. You may need to glue it if it is loose.
Then you can put the missing belt on.

That's not a bad idea. Good shout. It's never going to be the best tape playback, but at least it'll play.