Generator help EM

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LinuxLieutenant
Posts: 8
Joined: Tue Apr 28, 2020 9:17 pm

Generator help EM

Post by LinuxLieutenant »

Hello again, I've been having some trouble with the charging system in my 1960 sedan. I've looked through many of the previous threads relating to the generator and charging system with no luck. I put in a new battery and voltage regulator, and a rebuilt generator from California corvair. The gen light comes on and stays on with the engine running. I've checked the battery voltage with the engine running at high idle (12.4) and not running (12.6). I have also cleaned the contacts on the terminals and cables on the battery, regulator, and generator. I've polarized the generator by shorting the batt and arm terminals on the voltage regulator with an 8 inch piece of 16 gauge wire for a second after I reconnected the battery. This leads me to believe that the generator is bad, but the website says they're tested under load before being shipped. Is there any way to test the generator, or is there anything else I'm missing?

LinuxLieutenant
Posts: 8
Joined: Tue Apr 28, 2020 9:17 pm

Re: Generator help EM

Post by LinuxLieutenant »

I just tested the generator by running it as a motor and it spins nicely. However, I tested the voltage from the generator while the engine was running and it was only putting out .1-.2 volts. I tested for broken cables in the engine bay. The arm and field terminals on the generator and regulator show 0 resistance. The batt terminal on the regulator and the positive battery terminal also shows 0 resistance. All grounds seem to be good. This makes me believe the wiring, at least in the engine compartment, is good. Could the generator still be faulty? Or is it something else that is causing the battery to not charge?

joelsplace
Posts: 867
Joined: Wed Oct 13, 2010 12:51 pm
Location: Northlake, TX

Re: Generator help EM

Post by joelsplace »

The motor test is one of those electrical tests that if it passes it might be good but if it fails it is bad for certain. I had one that would motor fine but didn't put out any voltage. Took it off and tested everything several times. I finally gave up and installed another one and all is good.
If anyone knows how it can pass the motor test and still be bad let me know. I still haven't figured that one out. The only thing I've come up with is a broken wire that opens when trying to output current but stays connected when current is going the other direction.
114 Corvairs, 5 Ultravans and counting
Northlake, TX

LinuxLieutenant
Posts: 8
Joined: Tue Apr 28, 2020 9:17 pm

Re: Generator help EM

Post by LinuxLieutenant »

I checked the voltage coming from the generator while disconnected from the charging system and got .5 volts idle and 1.2 at about 2000 rpm. What might cause the voltage to drop to .1 when the generator is hooked up to the charging system?

joelsplace
Posts: 867
Joined: Wed Oct 13, 2010 12:51 pm
Location: Northlake, TX

Re: Generator help EM

Post by joelsplace »

It should have way higher output than that. I can't remember exactly but I want to say 50+ volts. Whatever the voltage should be it would have to be higher than normal charging voltage because it will fall drastically when a load is put on it.
114 Corvairs, 5 Ultravans and counting
Northlake, TX

LinuxLieutenant
Posts: 8
Joined: Tue Apr 28, 2020 9:17 pm

Re: Generator help EM

Post by LinuxLieutenant »

Hmm alright. I guess I'll try to return the generator, I'm not sure what the return policy on rebuilt parts is though.

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