I have a F7 B that started as a dummy from a newer super weight Athearn F-7A and B dummy set. Bought an older F-7 that did not have flywheels and used the motor, trucks and drive line to power the B unit. Ran fine, then they where stuck in the round house to sleep after I went DCC.
Pulled them about a month ago to clean up and list on E-Bay. A unit ran great and pulled like heck, OK no longer an E-Bay listing. But, sometimes the B unit would stop running? Open the shell and spin the drive shaft while under power and off she goes again. Then stops? Clean the arm (where brush contact the motor) and ran fine, then stopped again. I finally hard wired the motor and that seemed to fix it for sometime. Then it stopped again.
Thinking it might be the brushes or and springs. Or is it just time for a re motor?
I can get an Athearn Super Weight F-7 motor # 84040 for around $10.00. Or is it time to try an A-line motor?
Cuda Ken
I hate Rust
cudaken wrote: I have a F7 B that started as a dummy from a newer super weight Athearn F-7A and B dummy set. Bought an older F-7 that did not have flywheels and used the motor, trucks and drive line to power the B unit. Ran fine, then they where stuck in the round house to sleep after I went DCC. Pulled them about a month ago to clean up and list on E-Bay. A unit ran great and pulled like heck, OK no longer an E-Bay listing. But, sometimes the B unit would stop running? Open the shell and spin the drive shaft while under power and off she goes again. Then stops? Clean the arm (where brush contact the motor) and ran fine, then stopped again. I finally hard wired the motor and that seemed to fix it for sometime. Then it stopped again. Thinking it might be the brushes or and springs. Or is it just time for a re motor? I can get an Athearn Super Weight F-7 motor # 84040 for around $10.00. Or is it time to try an A-line motor? Cuda Ken
Almost sounds like a dead spot in the motor, based on your statement of "spin the drive shaft and it runs again." The commutator sections are each connected to motor windings and the most common failure is for a wire to come off. It's hard to see if you're not familiar with what you're looking for.
Best and cheapest way to repair it would just be to remotor it.
Tom, thanks for the quick answer and it all so makes since. From my old slot car days I use to rewire my motors so I know what you are talking about. I all so now know why the A runs better with out the B unit. With out one of the windings you lose power. B unit helps pulling but slows the train down after the grade.