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Sony TC-WR870 (TC-WR97ES): Capstans and belts replacement

M

MaxItaly

New Member
Hi all,

I need to replace both capstan motors and belts to my deck. I already own the belt-set but I haven't find the motors yet (Matsushita MMI-6H2L WK @12V). Anyway I've found the same motor from Pioneer as you can see by the pics attached below

309nhcp.jpg

PIONEER EXA 1241

2160ht.jpg

SONY X-3356-605-1 (THE ORIGINAL)

Of course I need first to replace the reels and weld the wires on the new lcb as well. Do you think it would work?

Thanks in advance for any suggestion.

Max

P.S.: please forgive my terribly english!
 
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I think your new motor would work fine, seeing that they have the same model number, specs and wiring. Back when I was playing with CD players we were swapping those cheap Mabuchis left and right with no problems.
 
Great, thanks soviet 123. By the way, in the meantime I have succeeded in installing new belts, but now I'm having a new, big trouble. When I turn on the unit, Deck B starts to rewind and fast forward for a little than stops and I can't get the tray to open by pressing the eject button. Even pressing on any other button (play, rec, pause, ff, rew, rec mute) the history repeats itself as you can see on this videoclip View My Video

Previously I haven't totally disassambled the decks in order to apply the mode belts, just unscrewed the screws and pulled back the plates a little bit, but evidently something went wrong with Deck B. I'm afraid that cam boss is no more proprely aligned. I've tried to manually rotate the gear with no luck. Since I am not able to disassamble it entirely, how do I get rid of it? Any suggestion would be greatly appreciated.

Edit: one more thing... on Deck B I've also pulled out the Flywheel (R FWD) in order to clean it and I imagine that the opposite washer has moved out from his place. Since I have no chance to open the tray, I cannot rescue it.
 
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Ok mates,

I did something I never thought I'd do. I've completely disassembled the deck and realigned
the Boss Cam with the Rotary Encoder, besides I've fixed up the mode lever.
10oh6h5.jpg


Now I can finally get the tray to open again and I'm still waiting for the motors to come.

View My Video

Unfortunately during disassembling/reassembling operations a capstan washer
is gone. How can I replace it? Thanx again.
 
Uh... That is way beyond me. Please wait patiently, your call will not be ignored by the good knowledgeable folks here.
 
New Capstan motors have finally arriverd! I’m going to replace them shortly and I'll let you know.

s3ekuq.jpg

A comparison of new and old Matsushita MMI-6H2LWK capstan motor
 
Done! New capstan motors are in place and work perfectly! No speed adjustment or regulation needed.
My Sony deck has been brought back to life!

2eai4bp.jpg

6od6s6.jpg


However, I'm still experiencing a couple of issues and maybe you can help me.
When I press play (or any other button) on both decks, tape moves for several minutes or few seconds then stops randomly. In the meanwhile, tape position led blinks on the control panel display (it seems to be a sensor fake). In your opinion, it may depend on a logical or mechanical failure?
Besides, playback produces sometimes a deep sound while in reverse mode sounds great or viceversa. It happens mainly with recorded tape, while with pre-recorded tapes no problem at all.
Heads, capstans and pinch rollers got demagnetized and cleaned. A head allignment is needed maybe? Thanks!
 
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Hi all, cassette sensor switches got cleaned with unifix spray and finally tape won't stop moving anymore. It hasn't been quite easy, to the end I spent a lot of time (and money) by replacing both capstan motors and 4 belts, but it was worth it! Thanx to all for the kind attention and patience. Cheers.
 
Alternative

Sometimes these motors are just dried up and can be refreshed with WD40. I apply it through the little black hole and also between the gap above the wire connections. Occasionally you will also need a drop of oil on the part of the motor where the drive shaft emerges although this isn't easy to apply without getting oil everywhere. All the motors I have done this to have speeded up considerably and needed no further adjustment.
 
How do you adjust speeds on these motors? Im retrofitting one onto a model that had a pot on the back for speed adjustment but these are controlled by the PCB. Can I graft a pot onto the solder terminals (there are 4)?
 
For normal speed, according to last above picture, connect +12V to red, ground to white, and a resistor in serial with a pot between the 2 other pins.

I would try a 10k resistor and a 4,7k pot.
 
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