Is this a high output Alt? Can you tell?

[munepit]

There is a guy selling this locally. Does this look like a high output alt? Should I grab it? Im waiting on this guy to get me some #s on it. Its $40.00

http://bakersfield.craigslist.org/pts/2141900142.html

 

[munepit]

The guy just told me he got it from a guy who works at a Alt. shop and he is the one saying it is high output. He said he is selling it cheap because he doesn't have any spec on the Alt.

Probably waste of time though.

 

[4xcrazy]

Looks like one my '78 Caddy used, as far as i knew, i didn't think you could tell just by looking if it was a "high output" or not.

 

[imiceman44]

The guy just told me he got it from a guy who works at a Alt. shop and he is the one saying it is high output. He said he is selling it cheap because he doesn't have any spec on the Alt.

Probably waste of time though.

It's a 12SI which normally was the high output versus the 10SI.
Still the highest stock 12 SI was 100amp from the cadillacs.

 

[cybrfire]

I think the output has to do with the number of windings inside or some such. I'd agree with 4xcrazy, from the outside the only thing you could do is look at a part number and find out what output that particular alternator had. Beyond that, you'll be taking the sellers word for it.

 

[munepit]

He said I could take it and have it tested. Seems like a lot of work though. Thanks guys!!!

 

[ktmoutfront]

My 200 amp at speed, 80 amp at idle looks just like the old one. Test is really the only way to tell.

 

[diesel4me]

All Gm altenators will have a amp rating and part number cast into the case--usually near the "ear" where one mounting bolt is or on the outer case somewhere,unless it was ground away at a rebuilder...its possible you could get one that has been reworked yet still has the original amp rating marked on it too,so yeah,having it load tested might well be the only sure way to know just what it'll put out...I'd guess anything over 100 amps is plenty for most of us,unless you have a huge winch,stero amps and a few million watt driving lights all on at once...dual batteries are better than a big altenator and just one battery,BTW..the batteries will deliver the power and the altenator only has to keep them fully charged that way,not also carry the brunt of the loads..