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gtv-racer
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current varies

Post by gtv-racer »

On my supercharged 75 3.0v6 america the current varies. Only with a warm engine....
Cold 100 pecent steady (0.1 volt change)

So far:
Rebuilt the dynamo. Bad bearings and collector so i replaced them.
Voltage regulator was only 3 years old and had 10K kilometers on it. Brushes looked nice.

Is it typical for a voltage regulator to go bad when it heats up?
Or something else i miss?
gtv-racer
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Re: current varies

Post by gtv-racer »

Could it be the new better fan i placed wich draws twice as much current (20amps meassured continues) causes this? How much extra has an America 3.0 dynamo for spare power?

Gonna check this weekend and temporary shutting the fan down at the trouble point for just a moment.
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MD
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Re: current varies

Post by MD »

gtv-racer

You are mixing terminologies which suggest to me this subject is not a strong point for you.
I suggest the KISS rule.
Remove your alternator and take it to an Auto Electrician Workshop. Have them test it under electrical load to see how much current it can deliver at what voltage. If there are any anomalies with the regulator or any winding failures with heat, this will show up under test. The cost outlay for this work will be absolutely minimal.

If the results come back to say the alternator is sound without any problems, then you need to look for issues with your car' wiring loom. Without being certain about the performance of the alternator in its own right, it makes the job of diagnosis much harder.
Transaxle Alfas Haul More Arse
gtv-racer
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Re: current varies

Post by gtv-racer »

Thanks MD but i already had tested it at a bench. It was oke and deliverd about 70amps. Don't know t current tunfortunatuly.... but i guess it's oke otherwise the opporater would have told me.

I recently change someting in the loom. Made an extra relay to switch fan,lambda and intercoolerpump so they only turn on with running engine
Maybe it is the signal wire for the relay.... don't know where i got it from anymore. Let's have a look this afternoon :?
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Zamani
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Re: current varies

Post by Zamani »

When you tested it on the bench, did you point a heat gun at the regulator?
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Re: current varies

Post by gtv-racer »

No Zamani. But it was a starting failing regulator because today it totaly failed. Also on cold engine no 14v...
Luckely i still had the old one so i popped out the old brushes and solderd new ones from the new one in the old one. :lol: everything is oke now.

It hard to find when something is working at one moment and the next it's bad...
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