Exciting the alternator?

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Re: Exciting the alternator?

Post by Marc » Mon Feb 20, 2017 9:26 pm

Even a tiny wire from that ground screw on the housing to the chassis will make it pass an ohmmeter test so you must do an active voltage-drop test under load (headlights, etc. all on) between the alternator housing and chassis ground. If it fails, check again between the housing and the pedestal to see if it's just due to the painted housing. If the main grounding point where the alternator housing contacts the saddle has high resistance, that little wire will take more of the current and quickly go up in smoke. The ground path must be capable of handling the rated output of the alternator (~55A for a stock one).

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