This unit is the worst running loco ( steam or diesel ) in my roster. It moves hesitantly at all speeds and is not a smooth runner. I have dismantled it a number of times and also replaced its decoder, and have also installed Tomar pick-ups on the tender for added electrical contact, to no avail. There doesn’t seem to be any valve gear bind as the mechanism runs well when the motor is removed. Could electrical p/up through the drivers or worm-spur gearing be at fault? Any suggestions, short of scrapping, would be appreciated. Thx in advance. Murray, Parksville B.C.
These models were notorious for having cracked nylon drive gears on the 3rd axle that had to be replaced. Initially, Athearn denied all liability for this fault and then provided free replacements to some modelers after a 2 or 3 year wait. I asked for a replacement several times and was promised that my name was on their waiting list, but never did get one. This cracked gear may be what is wrong with yours. I haven’t tried running mine for several years and don’t remember exactly what the symptoms were. I just put it back in the box and forgot about being able to get a replacement from Athearn.
If I remember correctly, Northwest Short line does have a replacement gear for the Athearn Mike. The USRA mike in general ran very good if all of the gears were in tack.
The gear sounds like the solution to the problem.
Yeah, it sounds like the gear is cracked. With a good gear, these are very smooth running locos, and can be made even better by the addition of tender pick-up. I bought two when they were first released, and have had no problems with the gears. When I figured out how to get them to pull a decent-size train, as shown here, I went out and bought two more, used, at a good price. All are used on very heavy trains, and, so far, no problems with the gears.
Wayne