alternator swap double-check

[785sp]

I'd appreciate a dose of the collective wisdom here.

I did the alternator swap on my 78, with a 105 amp Delco, and I'm testing over 13 volts across the battery terminals and across the engine-bay terminal. So far so good.

But, my dashboard gauge is now lower than with the malfunctioning stock unit. It reads about 10 volts. I've never cleaned the pod terminals, incidentally.

Is this a pod problem only? I hope so. Testing across the battery terminals is fool-proof, true?

Any reason why the pod gauge now tests lower?

Thanks,

Dave

[MPDano]

So you have an Aftermarket Gauge reading low? If so, how is it wired?

[Alan in AZ]

Originally Posted by 785sp

Testing across the battery terminals is fool-proof, true?

Yes to prove the alternator is working. It should read ~13.5v at 1000 RPM.

What made you think the old alternator was malfunctioning - the dash gauge? Its possible it was fine and actually putting out slighty more then the new one - hence lower reading now on the dash gauge??

Anyway - yes it sounds like a pod connection issue.

Alan

[785sp]

Alan,

Yes, the stock alternator, even after a rebuild, would start out fine, but would slowly lose voltage as the engine warmed up, until at operating temp it was basically dead. Never had that problem before on any vehicle, and the best explanation I've found is that the casing was warped/cracked somewhere, causing it to expand so that the armature would lose contact internally. Sort of makes sense, but I'm a beginner with electrics. Anyway, it's now a strong 13.5 across the battery with the Delco, so I'll breath easy. Thanks for the reply.

Dave