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I was at a friends house, about 10 miles from my house and as I got on the road to go home, I noticed that the volt guage was reading a little less then 12 volts. I immediately turned off the radio and turned off the lights. Lucky me it was just starting to get dark. I also reached under the dash and pulled the fuse for my fans. Immediately the guage went to 12 volts. I figure the engine will stay cool as long as I kept moving. The temp outside was in the 40s. Luckily I was able to limp home, engine temp never went about 190 degrees. Once in the garage, I pulled my multimeter and with the engine running measured the voltage at the alternator. The reading was a big fat 0 volts. Is it safe to assume that the alternator is dead? Any other tests I can do to double check this?

I am using the Mr. Amp alternator from DUI. Here is a link:
http://www.performancedistributors.com/alternator.htm

Andrew
 

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I'm not sure I trust your reading of 0 volts. Remember the alternatot output (large red wire) should be tied to the battery. It's sort of rare that a battery on a running car could read 0 volts. Something must be making the car run. I would re-check the voltages again. If the car will start, check the postive battery terminal, the alternator output, and the red wire on the horn relay. Measure these to a good clean ground. Post back what you find.
 

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Yep....should have 12 volts of battery there. If you have a true reading of zero, did you take the reading at the wire terminal connector? Sounds like the alt took a dump and took the fusible link with it.

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Steve Jack
-Concept One Pulleys and Brackets
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-Northern/Southern Rodder Magazine's "Jack'Stands" technical column author/originator
 

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hmm id check the cranking amps, and check the belts make sure they arent glazed of the hundreds of alternator tests ive done at my work ive never seen one read 0
 

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Steve
Just for information.
A 70 doesn't have a fusible link between the alternator and horn relay. The link is between the horn relay and the bulkhead connector. Car can't run if that link has popped. The main reason I think the initial reading may have been wrong.
 
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