While setting up consists and staging, testing prior to our show this weekend, http://www.ssmrc.org/
I found one of my favorite engines to have a horrible clicking/ grind. This Atlas Master GP40 has seen countless running time over the last 10 years. It really sounded like that “Dreadful” P2K cracked gear problem. I assumed there was some real serious drive issues and was prepared to switch out the shell to one of the many other units. This model has had many detail changes, far more than any other on my Chessie roster.
Off to the shop and removed the shell, test running still couldn’t located noise even after some lube and TLC. While checking motor shaft end play as I added a drop of oil, noticed that a flywheel was scraping the recessed frame. How it was clicking instead of the scrape or grind is beyond me. Twisting the flywheel further on the shaft to gain clearance fixed the problem. I have over a dozen of these Atlas units and never had anything like this happen, just like to post this if anyone else experiences the same issue.
Heading up the set up that 1972 Chessie consist w/ WM GP40 in RWB (Circus) in the lead, GP38 in B&O Blue and followed by that saved Chessie GP40. They will be pulling about 20+ Plug door box and Bulkhead and centerbeam lumber loads.
Interesting fix. Since this was a new problem I wonder what caused the flywheel to move so that it was touching the frame. You twisted it back into position. Was it a little loose?
Joe, actually the flywheel was quite tight on the motor shaft. Twisting to reposition was moving the other one. I had to shape a wood block and move it w/ a quick sharp rap. The only thing I can figure, is that this Atlas drive (14:1) was run w/ 2 SD50s (18:1) P2Ks for extended periods in the past. Not really the best thing…I did keep the Atlas (faster one) last pulling the weight of the 30+ hoppers so most of the time the SDs were just running along out front until needed for a grade. Decending a grade, however, is another story. .Over running of the drive an/or instant stops from shorts etc could be the only way it could have moved. Go figure.
I ran it today for quite a few hours along w/ 2 other matching Atlas units. All performed flawlessly. Of coarse the rest of the time I enjoyed running my somewhat new Bachman EM1, they are quite incredible in detail and performance- another fun day running trains.
This should hold true for any of the Atlas drives as they are quite similar in design. This would be the China prodution not any older Rocco or Kato versions.
