Alternator

[chockey]

My alternator was bouncing all over, from 8 volts to 16 volts and decided to replace it. Put in a rebuilt one and now it is holding steady at about 12+ volts. Is this about right? I recall that before the first one went bad it was at 13 volts, is it possible to get bad one. I purchased a heavy duty one which is 70 amps and that is what is called for.

I appreciate your input.
Chuck

[Dave L.]

Chuck - My guage reads 13-14. I also have the 70A alt option on my car.

Dave

[iron cross]

Voltage should read from 13.6 to 14.4 when running! Amps is merely the output of the unit to run accessories. Not all Vettes have high amp alternators.

[Nut]

Chuck.... mine runs around 14+. I put a 85amp alt in it last year after 21 years with the OEM 63 amp unit.

............ Nut

[chockey]

Thanks for the replies, mine is about 13 amps and decays to about 12.5 while driving. No starting problems or any other noticable things but I think that I got another 63 amp alternator not the 70 amp I asked for.

Chuck

[vettenick]

A quick check if the alternator is up to the task is to monitor the voltage after you've turned all of your items on; headlights, a/c, rear defogger, etc. If the voltage drops below 12.8 volts, you have a problem. If the voltage stays up where it should, then it's able to produce all the amps your car needs.

[81 Corvette]

quick side questions...where does the guage connect into the system. Mine had a bad connection someplace, as it often sits dead left but the car runs fine.

[vettenick]

The voltmeter is mounted on a printed circuit board behind the cluster lens. From there, it gets its power from the gauge fuse and it's connected through a pink/black wire. The other connection(its ground) is through a black wire that's grounded to the instrument panel ground. The ground location is on the driver's door hinge post right above the courtesy light switch.

[81 Corvette]

thanks