Trouble with my 32E gen

Anybody can help me?

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dariovital
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Joined: Sat Jul 31, 2021 9:12 pm
Bikes: Harley Davidson 1948 U model
Location: Argentina
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Trouble with my 32E gen

#1

Post by dariovital »

Hello friends! Greetings from Argentina. I've been a happy owner of a 1948 Model U Harley with a sidecar for a couple of months now. Since I acquired it, I have been improving many details typical of a motorcycle that has its years, and for many of the last it has been standing still. I decided to remove the dynamo for examination and cleaning, as it was not able (even increasing engine revs) to get the GEN light on the dash to turn off, so I assumed the dynamo was not charging. The first thing I notice, is that it was missing the metal and Bakelite washers between the conmutador and the back cover. Also the insulating papers of the field terminal coil and those of the switch terminal. Also the cables of the shunt field coils were badly connected. Once these problems have been solved (place the corresponding washers, the insulating papers and connect the cables according to what the manual explains), try to test if the dynamo rotated as a motor when connecting current from the battery, but no ... it does not rotate. -It is clear that according to videos I have seen, connect the positive of the battery to the SWITCH and RELAY terminals, and the negative to the housing-. The surprise was that I accidentally connected the positive battery cable to the RELAY terminal, and the negative to the third brush holder and now if I WORK AS A MOTOR! .. what could be happening here ??? have I connected or isolated something wrong? (If I can, I will try to upload a video. That is more graphic than all words). Thank you in advance for your comments!
dariovital
Junior Member
Posts: 9
Joined: Sat Jul 31, 2021 9:12 pm
Bikes: Harley Davidson 1948 U model
Location: Argentina
Has thanked: 3 times

Re: Trouble with my 32E gen

#2

Post by dariovital »

here I leave the link to the video:
Pascal
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Re: Trouble with my 32E gen

#3

Post by Pascal »

Both the SWITCH and RELAY post are positive;
SWITCH receives positive current from the battery as soon as you turn the switch.
This charges the generator.
When the motor turns, so does the generator, thus building up voltage.
When the voltage inside the fieldcoils rises to the point it surpases the battery-voltage, the cut-out opens and charges the battery.

Connecting the third brush to earth/ minus, closes the ring and yes; makes the rotor spin.
Effectively, you've created an electromotor...
dariovital
Junior Member
Posts: 9
Joined: Sat Jul 31, 2021 9:12 pm
Bikes: Harley Davidson 1948 U model
Location: Argentina
Has thanked: 3 times

Re: Trouble with my 32E gen

#4

Post by dariovital »

Thank you very much Pascal for your answer !!! My question (and doubt) is, why the generator does not turn when testing as it is - that is, when connecting + to both SWITCH and RELAY terminals, and - to the housing? :cry: ). How can I test the current output of the generator?
Is this generator working well?
Pascal
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Re: Trouble with my 32E gen

#5

Post by Pascal »

You can test the genny on a workbench; put it in a clamp and spin the genny by hand (I use a bent nail or spoke thru the holes of the oilslinger) while putting a multimeter (set on 20A) with negative on the housing and positive on RELAY post.
It should read 2-2,5 amps..if not; set the third brush.
dariovital
Junior Member
Posts: 9
Joined: Sat Jul 31, 2021 9:12 pm
Bikes: Harley Davidson 1948 U model
Location: Argentina
Has thanked: 3 times

Re: Trouble with my 32E gen

#6

Post by dariovital »

Thank you very much Pascal for the help! This weekend I will do the test as you recommend. Then I will comment on the results!
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