n scale big boy

[mls1621]

If you can move the rear drivers with your finger, the drive gear of the motor isn't engaged.

One screw, accessable through the stack, will allow removal of the boiler shell. Lift from the front, a small tab at the rear of the boiler anchors that end.

The motor is held in place by two plastic clips. If the rear clip is missing or broken, the motor may have lifted, disengaging the worm gear that drives the rear set of drivers.

A piece of debris would bind the gear train, you would not be able to move it with your finger.

Another option is that there is a broken gear in the rear driver set. If that is the case, some parts may be available through Con Cor.

I've had mine apart several times for cleaning and lubrication. With the boiler shell removed you can see what's really going on inside.

I hope this helps,

Mike
St Louis

[andyhjn]

thanks for your insight maxx

[Anonymous]

There may be a small piece of debris in the drive train keeping the loco from starting unless you nudge it. one of my FA1 locos had a small iron filing in a gear and it would start unless i nudged it. I removed it and it now moves under its own will. There may also be something a little too tight in the drive train itself for the electric motor to overcome to start movement. Just a thought. I have little knowledge of that particular loco sorry.

[andyhjn]

having a problem with the rear drivers on a rivarossi big boy not turning under power. they freewheel if pushed with a finger[:(]. also the loco doesn't waqnt to start unless given a little nudge. any insights would be appreciated.
thanks andy.