Have cleaned commutator and slots, brush plate and existing brushes; I have checked continuity. All appear in good working order. When I connect power, the motor just chatters and does not spin. Why?
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Did this ever run for you?
How are you connecting power?
Thanks Rob. No, this unit has not been run for me. My friend picked it up at a recent train show and wants it restored electro-mechanically for a themed repaint job. When I apply power to the brush contacts, the motor only chatters and does not spin. In my Greenberg's Repair manual for postwar equipment, it says this unit will run on either AC or DC power. When I connect it to power, it chatters like a DC powered engine on an AC powered track system. I am puzzled.
It is an AC motor and you cannot just put power to the brushes . The field coil needs power too. I stole this from another forum member.
1 Take a jumper wire and connect one brush holder to the metal tab between the brush holders (this is the field tab)
2 attach one test lead to the other brush holder.
3 attach the other test lead to the metal solder tab on the side or the motor, or simply touch it to the metal side of the motor.
The motor should run.
Exchange the wires going to the brush holder, and the motor should run in the opposite direction.
You might check the armature coils. They all should give the same resistance. The one on my Marx 333 was bad and got one on ebay. The below link can rewind yours if bad.
Charlie
@Ralph736 posted:When I apply power to the brush contacts, the motor only chatters and does not spin...
That is the problem & why I asked.
Being a series-wound AC-DC motor, the field must be connected in series with the armature.
