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MG MGA - Delco Alternator Conversion

Hello everyone,

I'm no electrical genius - how do I test the output of the charging sytem to the batt with a simple voltage tester? I've heard charging should be less that 15 amps?

I've done a alternator conversion and want to make sure I don't over cook the battery.

Thanks
John
John

When running, the voltage at the output of the alternator should be ~14.5-15.5 volts or so. The actual number depends on the alternator and the ambient temperature. The hotter it is, the lower the output voltage and vice-versa. Easily discernable from the 12.6-13.0 volts at the same terminal when the engine is not running. As far as charging current goes, there is no actual control for that. There is a current limit, normally set above the rating of the alternator (depends on the model you have chosen). The amount of current going to the battery vs. the rest of the car is determined solely on the battery's internal impedence and the output voltage of the alternator.

This is no different than a modern car. I would suggest installing a fuseable link though, just in case.....

Chuck
Chuck Schaefer

Agree entirely with all Chuck has advised, but he omitted to tell you where to measure. Simply place your volt meter across the battery terminals. Ensure if you are using a multimeter that you have the leads in the voltage holes and not current, otherwise you will experience a slight bang as its fuse blows. With the engine not running you will get about 12 to 13V, running it should be about 14.5V.
Bob (robert)

This thread was discussed on 26/04/2005

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