Another 3 brush conversion question

Electrical issues
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RexEstes
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Another 3 brush conversion question

#1

Post by RexEstes »

Not sure whats up but I'm not getting my genny to motor after rewiring the field coils as a two brush.

When I apply 6v, the commutator doesn't want to rotate- acts like it's electrically locked. Remove powe and it rotates freely. Tried motoring per this video: https://youtu.be/urYTz1hKn54

I reconnected the field coils per service bulletin 418. Top coil bottom field lead joins bottom coil and top field lead on the switch terminal. The remaining leads get connected to the top (+) brush.

I checked for ground on both relay and switch terminals both have infinite resistance to the case. Both coils have 3-5 ohms resistance so I don't think I have a broken wire. What could the issue be?

Fyi this is a 32e running 6v.

Rex
1950Panhead
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Re: Another 3 brush conversion question

#2

Post by 1950Panhead »

Not sure whats up but I'm not getting my genny to motor after rewiring the field coils as a two brush.
You removed the adjustable brush ?
What did you do with the wire ?
RexEstes
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Re: Another 3 brush conversion question

#3

Post by RexEstes »

I removed the third brush and the wire got rerouted to the switch terminal.
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Re: Another 3 brush conversion question

#4

Post by 1950Panhead »

I removed the third brush and the wire got rerouted to the switch terminal.
The 32e is two generators, the lower field coil runs the ignition, the upper field coil is activated when you turn the ignition switch to the 2nd position and runs the lights.
You can wire the field coils in series however then you need a voltage regulator and if you draw more then 10 amps the generator will over heat and destroy the armature.
If you want more more for lights or hand warmer get a model 58 or 61 generator which makes more power.
I know of three different 418 bulletins, one of them describes converting a fan cooled police generator from three brush to two brush, the police generators differ from 32e generators and makes more power.
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Re: Another 3 brush conversion question

#5

Post by Frankenstein »

The symptom you describe is usually a result of the fields being ungrounded in your test jig. Or, possibly, the polarity of the two fields being wired in opposition to each other.

With the genny wired as a stock 3 brush genny,
Try this:
Lead that is on relay terminal stays there.
Lead that was on switch terminal is moved to Relay terminal
(each field now has one wire connected to Relay terminal)
Lead that was on third brush is moved to switch terminal
Lead that was grounded is moved to switch terminal

(Switch terminal now has 2 leads on it)
One that used to ground through the third brush, one that used to be directly connected to ground.

Applying power to the Relay terminal, and grounding both the generator case and the switch terminal will cause the generator to motor.
DD
RexEstes
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Re: Another 3 brush conversion question

#6

Post by RexEstes »

Thanks DD, found a bad joint on my alligator clip which was not allowing proper grounding from terminal to case.

Seriously scratched my head on this one. I mean come on, it's just 4 wires and two terminals... makes sense it was the bench setup.

Thanks
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