alternator pulsating - Diesel Bombers



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Old 09-01-2011, 02:59 PM
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Default alternator pulsating

I can see a pulsation in the headlights and thinking that this may be related to my other issue I started to trace the power wires and found that the power from the alternator it self is pulsing. I wired in an external voltage regulator due to ecm problem. The pulse is fast and I can see it with a test light but not with a multimeter. I also cleaned and added grounds to the frame and to the firewall and ran a ground from the alternator to the negative on the battery. Still pulsing. Any help would be appreceated. Thanks
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Old 09-02-2011, 03:05 AM
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I had the same problem awhile back and mine was a fuseable link that was bad sometimes it would make connection and sometimes it wouldn't.
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Old 09-02-2011, 07:18 AM
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Default alternator pulsating

New alt, rectifier bridge is on it's way out. Take your digital multimeter,
Put it on volts/ac and put your Positive lead at the alternator output and the negative on the alternator case. Iirc you should see no more than .5v ac coming out of your alt.


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Old 09-02-2011, 08:08 AM
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Check for bad connections before you do anything. I had the same issue with mine a while back. Turns out, it was a poor connection in the voltage sensor wire that goes from the alternator to the voltage regulator. Use some test wires on alligator clips bypass the OEM wiring and see if this fixes the problem.
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Old 09-02-2011, 01:35 PM
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I wired in an external voltage regulator a while back and I have rechecked all of the connections. I should also mention that this is a rebuilt alternator from a reputable local company.
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Old 09-03-2011, 12:51 AM
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Like I said mine done the exact same thing and it was a fuseable link its the little white one that's attached to the orange one I cut it out and put in a 30 amp circuit breakerand it fixed my problem.If I would have figured that out the first time I wouldn't have had to run a million ground wires and change the alternator!
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Old 09-03-2011, 09:50 AM
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I will check the fuseable links. Thanks
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Old 09-03-2011, 09:26 PM
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When I checked mine it didn't feel bad but it was!
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