Generator Issues

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Kiwi Cortina
Posts: 454
Joined: Tue Dec 20, 2011 7:54 pm
Location: Novato Ca

Generator Issues

Post by Kiwi Cortina »

On the 67 GT I'm working on the Gen light will not go off. The generator was refurbed about 500 miles before the car was taken off the road, going by a receipt and the date punched onto the generator itself. I tried testing it by removing the 2 wires, putting a jumper wire across the 2 spades and putting the volt meter to the generator and running engine. Results a little over 1 volt. I have another brand new Generator and get the same results. Any suggestions?

Thanks
peteleo
Posts: 1332
Joined: Sun Aug 24, 2008 11:57 am
Location: San Mateo,California

Post by peteleo »

Do you still get 1 v output when you rev the engine above 2K ? If so, could be a disconnected brush. Run the spare generator as a motor by connecting the two terminals together attach cable to positive post, negative side to gen. bracket. Should spin freely.
Bob_S
Posts: 407
Joined: Fri Nov 27, 2009 8:22 pm
Location: Michigan, USA

Post by Bob_S »

ITs been a loooong time since I messed with generators. But as I remember, sometimes you have to polarize the generator to get it to work. Generators can be neg or pos ground depending on how they are polarize.
Bob_S
First car 70 Cortina GT
Bob_S
Posts: 407
Joined: Fri Nov 27, 2009 8:22 pm
Location: Michigan, USA

Post by Bob_S »

Here is an article on how to polarize a generator for either positive or negative ground.

http://fergusontractors.org/nfs/wp-cont ... erator.pdf
Bob_S
First car 70 Cortina GT
Kiwi Cortina
Posts: 454
Joined: Tue Dec 20, 2011 7:54 pm
Location: Novato Ca

Post by Kiwi Cortina »

Thanks Gentleman, Will try over the weekend.
Kiwi Cortina
Posts: 454
Joined: Tue Dec 20, 2011 7:54 pm
Location: Novato Ca

Post by Kiwi Cortina »

Ok, tried both generators and both spin freely when connected to a battery, tried polarizing and still no volt output and the gen light is still on. any other suggestions?

Thanks
peteleo
Posts: 1332
Joined: Sun Aug 24, 2008 11:57 am
Location: San Mateo,California

Post by peteleo »

Gens are probably ok. I think there is an issue with the voltage reg. Most common problem with these is the cut-out circuit where the contacts are too wide. Also check that vol reg is grounded. There is a short black wire connected to the end of the reg to ground. Cleaning both ends.
JAN
Posts: 181
Joined: Sun Oct 21, 2007 6:57 am
Location: Wigan, UK

Post by JAN »

The test you did in the first post says that the generator itself is not functioning, but I assume that you raised the engine speed during the test? With no regulation, the voltage should rise in proportion to the rise in rpm, and should go up beyond 18V if you take the rpm up to this and get that result, the generator is fine and the fault is the regulator or regulator earth, or the wiring between. If the generator doesn't do this, the fault is there.
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