Slow RW in both decks GF-767

[ElectroKid]

Hi all,

I had the small rubber tires changed,
The flywheel flat belt changed, size approximately measured - any affect on RW speed at all ?
The capstan square belts changed, size approximately measured - any affect on RW speed ?
In deck 2 I had sluggish spindle - I found the shaft has been slightly pushed inside so I pulled it out 1-2mm and now is running smooth.

What else should be checked ?
I guess that only the tires and the flywheel do this job - right?
Could it be the tires do not clutch enough to the plastic wheel on the flywheel - how can it be fixed?
Could it be faulty springs that do not proper engage the tires mechanism ?
It's hard to diagnose since the unit has to be re-assembled for testings thus cannot see action inside...


...

 

[baddboybill]

Did you try cleaning surface of flywheels where the tires ride? Or since you replaced tires, are they the same height as old ones?


Bad Boy Bill

 

[ElectroKid]

Yes to both.
Tires are orig from a 777, same height or I should say thickness compared to the broken ones I had.
The plastic grip surface on the flywheel was cleaned with alcohol (it was pretty much clean already).

Thinking of it, I remember wondering what is the adjustmet on the inner flywheel for... maybe it was moved during working on it...
It could be too strong grip (when rewinding it kinda start and then slow down like wobbling motion)
But then again, it looks like there is not enough gripping force between them so maybe the tire is not getting close enough - so may need to use a higher or wider tire
Trying to grab the spindle while RW, it has somewhat lower force than the FF one

 

[baddboybill]

So you put on used tires? There is the problem most likely then. The tires are probably dried up and not getting good traction.


Bad Boy Bill

 

[baddboybill]

And the tire that rides the capstan in pic is for the play mode. Not rewind.


Bad Boy Bill

 

[ElectroKid]

Yes the tires are used but I checked them thoroughly and they seemed to me like new with no small cracks or dry marks...
They replaced my broken ones, and FF and RW did work ok for sometime as I recollect...
Maybe they should be soaked in oil overnight and see if they get better traction? But it's strage tho...
Is it reasonable that the RW mode needs more force than FF mode that works perfect ?

 

[ElectroKid]

Finally after a night of olive-oil soak this Issue is now fixed.
Also gave the flywheel inner plastic wheel a good alcohol clean and the RW is now much much better.
It's amazing how the tires seemed so clean yet they did not grab at all (they were squeaking).
I just hope this is not a temporary fix and they'll stay plump for long time.
Thanks.

 

[ElectroKid]

And the tire that rides the capstan in pic is for the play mode. Not rewind. Bad Boy Bill

Yes, the flat belt seen in pic above you called 'tire' is for play mode - I know.
The soaking was done for the small rubber tires in the 1st pic- now the traction has very good force.
Thanks BBB

 

[baddboybill]

Olive oil? We talking about Popeye GF ?? just kidding. Very interesting using olive oil. Let us know how it does after some use.


Bad Boy Bill

 

[ElectroKid]

Olive oil? We talking about Popeye GF ?? just kidding. Very interesting using olive oil. Let us know how it does after some use.


Bad Boy Bill

Yep, Olive - extra virgin type ....
I'll see how it performs after some use (box remains open for some cleaning)

 

[ElectroKid]

well, the slow Play+RW in Deck-1 is kinda solved. on some c90 cassettes where the tape is closer to beginning, this introduces too much drag...
but on Deck-2 Play+RW close to the beginning has noise resulting from the 2 cog wheels not fully interlocking (one on the spindle which is driven by another smaller one)...they slip and I can't figure why
maybe i'll shoot a video later

 

[baddboybill]

That's because there's a tire that drives the cogs are bad.


Bad Boy Bill

 

[stosoorok]

Do RW/FW still work? I'm facing exactly the same problem.