Overheating alternator? (New question)

[rendyx]

Just put in my new alternator and serpentine belt, but they have done a few odd things. First, when I applied plenty of electrical load in the car, what I assume was the belt began to chirp. We loosened the idler pully a little, as the alternatpully had become very hot. This caused it to chirp even sooner under electrical load, but the pully did not feel as hot. So we really tightened up the pully, and this made it shut up, although the pully became slightly hot. I'm not quite sure what it is, could it be because the new belt does not have as tall of ribs on it as the old one, and does not have small slits in the ribs (so the ribs are not a long line around the belt, but rather dashes)? Any ideas?

<small>[ December 29, 2002, 06:15 PM: Message edited by: rendyx ]</small>

 

[SHOZ123]

How hot is hot? It will get too hot to touch under normal use. I have read that until the ribs start to chunk out the belt is good. the small cracks in the individual ribs is OK.

 

[rendyx]

Okay, from what you said, it's fine. I drove around some, checked the temp again, and there was a little warmth above it. Now, is it supposed to be the pully that is producing heat? And second, should I break in the alternator at all? I'm thinking of taking it easy on the thing for a day or two, before applying heavy loads, or winding the engine way up.

 

[SHOZ123]

An alternator is an electric motor in reverse. Just as the magnetic field in a motor induces heat from the current running through the windings the alternator will to. In the alternator the tension of the belt is the major contributor to the load on the bearings. In a motor it is the driven load.

 

[rendyx]

Well, I just came home from work, and as I was listening to some music and driving, I heard some sort of squealing noise. Yes, that belt was slipping again. Would you people say it needs to be tightened more? And is there a way to determine the tension without some tool nobody has? Thanks again.

Edit: I found a post in which Scott Patterson said you should tighten it enough so that it has about 1/4" play under firm finger pressure in the longest part. I assume this is right at the bottom of the belt, parallel to the ground. Right now I'd say it has about half that much play between the alternator and idler pulley!

<small>[ December 29, 2002, 05:45 PM: Message edited by: rendyx ]</small>