So I replaced my power steering pump, because the old one had play in the pulley.

Put on a new belt, a few days later, it snapped under acceleration on the highway... booo.

So I checked the alignment again, it seems good.
After searching, I will check the surfaces of the pulleys to see if they are damaged.

Other than that, what can cause a new belt to snap so soon?
How tight should it be on?

Thanks again...

The tightness is a little tricky to measure unless you have one of those gauges. I do not have air conditioning and I keep it tight enough so if you grab the middle of the belt with 2 fingers you can just about turn it 180 degrees.

Originally posted by ner947
The tightness is a little tricky to measure unless you have one of those gauges. I do not have air conditioning and I keep it tight enough so if you grab the middle of the belt with 2 fingers you can just about turn it 180 degrees.

Really? thats pretty loose then?
I could barely turn mine... 15degrees?

Too loose it will slip and squeal. Too tight and you damage the bearings for the pulley.
If you push straight down on it with a decent amount of pressure, you should have about 1/4- 1/2" play.

new belts will stretch a little so you need to re-adjust the tension after the car has been running for a few minutes

Originally posted by juggalo
new belts will stretch a little so you need to re-adjust the tension after the car has been running for a few minutes

Whoa. Haven't seen you in a while. }(

I wish i had the belt so I could examine it... then I'd know if i broke it, or threw the belt.

What if the belt didn't snap and was thrown off?

If you're throwing belts, either the tensioner is bent/loose, your accessories aren't bolted down, or your crankshaft pulley isn't tightened down all the way with an impact wrench. If you have a UDP or rebuilt engine, the latter is most likely the problem.