GM alternator hum...

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Poser said:
An alternator is going to generate heat when it is under load, and trying to charge a dead battery at idle or higher RPMS is going to be asking a lot from it and probably damage it. It is not a good idea to start a vehicle with a dead battery and try and bring the battery back up to a proper level of charge using the alternator.

Hot to the touch:

Warm, you can keep your hand on it is fine; warm to the point that you do not want to touch it or cannot keep your hand on it is not good.



No worries bud.

:beer:
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Thanks for the input. It was definitely not too hot to touch...just warm.
 
Do not use a torx bit or anything other than a 1/2" drive ratchet to take the tension off that belt!



You do not need to disassemble that tensioner to release belt tension. Just insert a ratchet into that square drive and swing it out of the way against the spring tension.

Remove the belt and let the tensioner return to where it stops.
 
Poser said:
Do not use a torx bit or anything other than a 1/2" drive ratchet to take the tension off that belt!



You do not need to disassemble that tensioner to release belt tension. Just insert a ratchet into that square drive and swing it out of the way against the spring tension.

Remove the belt and let the tensioner return to where it stops.
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Very nice. Thanks, man!
 
Most oreilys alternators are lifetime warranty. IMO they need to be. I went through about 8 alternators between two mustangs in 10 years. Multiple issues with the voltage regulators inside them. I never worried too much because I learned to swap it in under 10 min and they were always in stock. My :princess: wasn't a fan.
 
Skillet said:
So, does anyone make one that is not a piece of garbage?
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Like I said in my PM, I've always had good luck with Napa rebuilds.

The alternator in my truck is original, from 1993. Maybe a used one from the junkyard?

BTW Poser, my truck doesn't get driven much and I've had some trouble with the door lock relay draining the batteries (2 of them). It has been jump-started countless times in it's 19 years with the alternator then charging the two batteries. I'm guessing it has gone through about 6 pairs of batteries in this time.

I'm not saying it's good for the alternator, just that this one is a survivor. I never even thought about it before now. It is a c3500, so it probably has a 100amp alternator or some such.
 
Skillet said:
So, does anyone make one that is not a piece of garbage?
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I find the best alternator is one buit by an alternator/starter shop. Considering that is all they do. Might try to find one in your town. Most mid size towns have at least one. They will do it right.
 
What about Tuff Stuff?

They are brand new...

100 amp / $90


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Skillet said:
Also, if I went to a 100 or 140 amp alternator, what kind of wiring upgrades would I need to make with the painless harness, if anything?

The one I have is 85 amp.
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When I went from my stock 45-amp Denso to a 200-amp Mean Green, I replaced my battery and starter ground cables and the battery to starter positive cable with 0-gauge marine cable and the alternator to battery positive cable with 1 or 2 gauge (don't remember which), and added an extra 1 or 2 gauge ground cable from the alternator also. That, and a WiredWagon headlight harness. Works well, and no more dimming of anything at idle.
 
Well, I am going to Napa in the morning to try and replace this O'reilly pos.

They have a 140 amp that should work.

Is that going to be okay in here with the winch and if I want to do some extra lights, etc?

BTW, Poser...thanks for the tip on the tensioner, I could have made that operation WAY more difficult than it was.
 
Skillet said:
BTW, Poser...thanks for the tip on the tensioner, I could have made that operation WAY more difficult than it was.
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Yes, and sorry Skillet for suggesting you booger up that torx head with an Allen wrench jammed in there. I forgot all about using that square opening to loosen the tensioner. Good luck.
 
Got the NAPA 140 amp and installed. Much larger than the 85 amp.

After install, noticed it ran hot...so, I researched and decided to ground directly to the battery and run a larger wire to the 100 amp fuse that is part of the Painless system...

No change.

So, I need to say that I am getting 14 volts all around and battery is up to par...seems to be doing great.

Why so hot? Maybe the higher amp setup?
 
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