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Nakamichi BX-100/125/150 Cam motor repair

I was able to restore the cam motor by follow the excellent directions on Pieter's KB. What a write up! I loosely buttoned the transport back and tested it. It plays, FF/RWD like before. I'm waiting for the tire and relay to arrive to complete the restoration!
I played the deck for 1 hour and heard intermittent squeal sound coming from the capstan motor. Tapping it would quite it but would eventually return. It's a sealed motor so cleaning it would be a chore I assume. Has anyone attempted to clean the motor?
 
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Update: I disassembled the capstan motor, the process was easy. I provided some details and I hope it will help someone with similar squeaking/light grinding noises coming from the motor.

Remove motor and desolder the +/- connections Make note of polarity.
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Using needle nose pliers, I bent the collars out slightly enough to separate the cover from the body.
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Once removed, I gently removed the brush section from the motor. You will need to tilt the brush section and mind the delicate brushes. Set aside

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Clean the bottom and top bearings, and lubricate
Bottom
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Top
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The inside of the motor, shaft and contacts were dirty. Clean it, lube it, enjoy it!
I returned the motor back to it's natural habitat. Bent the collars back the best I can and soldered a few dabs to keep it closed. The motor runs perfectly silent now.

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Ready to rock for another ~30 yrs
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12 years later and the cam motor has failed again. The deck was used intermittently for most of that, and went back into service when my CT-F800 started having problems about 8 months ago. From that point on it was used daily for 6 months and then failed again. So this time I'm going with a replacement motor.

Charlie.
 
Did you replace the conductive paint beneath the brush contacts with solder, as outlined in a link above?
 
Correct. The cam motors never wear out, as they only run a second or two at a time. The solder fix has been 100% and is almost as easy (or easier) than a replacement motor, as the replacements don’t fit without an adapter plate or machining of the holes and screw heads.

And note that this fix is valid for the entire CR, Cassette Deck, and DR series as well. I do it automatically on every one that I service.
 
BTW, I just had two consecutive cases of motors refurbished including soldering that then ran too fast. I had to slow them down.
 
I bought a motor and adapter plate off of eBay and installed it yesterday. I had to trim some metal for it to clear, that was the hardest part. For $31 including shipping, this was a lot easier than opening up that cam motor again. I took the opportunity to lube everything while I was in there. It’s working great now. New motor doesn’t make much more noise than the old one, especially after lubing the cam and worm gear. Now if I could just find a 3D print file for a gear drive conversion and I’ll be a happy man.

Charlie.
 
@ChopperChas
I did this mod to several BX back a few years ago, and one of them was a BX1 that had the gear mod. It was the best sounding BX, and made the best tapes...
I only took one photo of the mechanism, because I didn't even think of 3D printing the parts or I'd have paid closer attention.
Here is the photo... how many gears would be needed? 4?

BX1 Gear Drive.png
 
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