I have a PS2 MTH Premier Shay (3 truck WM 6). It shakes and makes a grinding noise in reverse(and only in reverse) unless pressure is applied (by hand) on the top of the engine pressing it downwards,then it runs smoothly. I left it sit on a shelf for about a year due to a number of back to back moves. Now that Im home again I put it on the track to run it, and it ran perfectly forwards and baclwards for a couple of minutes, then while backing it stopped, grinding noise came back, engine shaking violently. Of course I stopped running it to avoid damage, although it does continue to operate normally in forward.
Any suggestions for repairing the engine or further diagnosing the issue?
Thanks!