@dolson
All, I had a chance to take a look at one of the Moguls this past Saturday at our D3 meet at Norm's. I will say it is quite a nice locomotive. The sounds are phenomenal. I did have the chance to evaluate the motion and drive system of the unit and wanted to provide some feedback on what I saw. I hope it may be of some help to resolve the issues.
First, wanted to say that I owned the original TMCC version (CN version) and it runs flawlessly, great slow speed motion and not jerky at all.
I had the chance to run the Grand Trunk version this Saturday, and this is what I had noticed:
- At slow speed the engine did have a lurch to it (especially in the forward direction). It clears up at higher speed. (Note, gearbox was properly lubricated so no lack of lube issues.
- I was facing the left side of the loco and the 1st thing I noticed when commanding the loco forward with the Cab 2 was the center drive wheel moved towards me. It was pronounced since the drive gear shifts outwards as well. I would say 1/2 mm or more of end play in the center drive axle.
- After playing with the engine forward and backward, quite slowly, we were able to get the engine to lock up trying to move forward. With just a slight push on the drive wheel opposite me the gears freed up and it moved forward.
- There were no issues with brake wheel stiction or traction tire issues.
This leads me to question either the gear mesh between the drive axle and motor, or the tolerance of motor gear to the drive gear on the middle axle. The friend whom I had sold my TMCC Mogul to went back and checked what happens when drives the engine forward at slow speed. He found no movement of the drive wheel towards him (ie, no end play).
Not sure if there could be a gear tooth pitch issue on motor or axle, or just the alignment of the motor and drive axle.
My 2 cents, hope it may be of some help in diagnosis.
