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Old 08-10-2014, 11:02 AM
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patrickt patrickt is offline
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Default Now You Should Perform a Voltage Drop Test

Since you're replacing the wires, connectors, and alternator itself, once you get the new stuff in you should take five minutes and perform a voltage drop test on the charging circuit (both positive and ground). It will tell you if you have a problem anywhere along the circuit. The picture that I'm posting below shows a 100 amp charge, so the potential difference between battery and alternator is acceptable at 700 millivolts. For your 65 amp alternator, I would only expect 400 millivolts or less both on the positive side and the ground side. Dan, I know you hate any sort of electrical test, but this one is not only the easiest, but it's the best. Just put your VOM's leads as shown, with the car running, and measure the voltage just like you see on the pic. If you register a number that's larger than .4 volt, on either the positive side or ground side, then you have more work to do. If it's less than that, all is well. You can do this.



Last edited by patrickt; 10-28-2016 at 09:48 AM..
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