Hanging Monorail Motor Stripdown & Fix

I have a Shonan 5000 hanging monorail unit that's never been right since I got it, it's always been erratic and jerky, with a marked tendency to snag and stop at every rail joint unless alignment is absolutely perfect. Today I finally got around to stripping it down so that I could investigate.

First I'll show the gearbox stripdown sequence for reference:



Everything cleaned up, motor oiled, gears and spindles greased, re-assembled and although it was all running smoother and quieter, the basic problem still existed.  I did notice two things though, as indicated here:



A: two of the spring-loaded wheels that push the rubber drive-wheel against the track have lumps on them, artifacts remaining from the moulding process. I trimmed and filed these smooth.

B: one of the wheels is slightly out of alignment with its opposite number.

Stripping the motor unit down again, I found that slacking off the screw that secures the spring-loaded wheels, C, by about 1/3 of a turn, bought the offending wheel back into alignment.

Result, the unit now runs fine, negotiating track joints without complaint. Two hours on a rainy afternoon well spent!

[ripley802]

Very nice tutorial and repair on this one Chrisjo.

[Super]

Fantastic Dr Chris and perfect up-close pictures of the interior of the Hanging Monorail Workings showing what was wrong and how you went about fixing it. I am going to move this Thread to our 'Modification Guides Forum for easy searching for those seeking out answers or at least the gear configuration which is important if one doesn't know how to put it back together. Thanks for the detailed update.