Pulley Issue

[jknowles87]

Hi, I have a 1988 Chevy C-2500 Scottsdale 2WD, 5.7L 350, 700-4R that has has a squeal/grinding noise coming from one of the pulleys. I have had 2 belts put on, as well as an idler pulley replaced, and the problem is still there. Lately this has been the situation: when idling at a light, i hear nothing. As i accelerate, I can hear it, then as my foot lets off the gas it dimenishes. From watching it run, it looks as if the smog pump pulley is wobbly (compared to the others). If i spray belt dressing onto it, the noise disappears in all cases, even under acceleration. This "fix" lasts anywhere from 2 to 48 hours, upon which it begins again.

I am thinking I should remove the pump and pulley to solve the issue rather than pumping money into a new one. Can i run a shorter belt around the other accessories and essentially delete the smog pump, or will i have to remove it and install something there?

[BajaScout]

I once replaced by belt with a belt that was supposed to be superior than the stock belt. It had a criss cross pattern instead on the straight line pattern. It always squeeled and I then replaced it with a stock belt. No squeeling with the stock belt. Probably not the problem you have, but I thought I would throw it out there since it happened to me.

[2000CAYukon]

I have not heard of a bypass pulley for the smog pump (probably illegal). Perhaps you can have someone listen to it with an automotive stethoscope to find out where the noise is coming from.

A bad tensioner can also cause belt noise. I have 139K miles on my 90 K1500 and I have probably replaced the tensioner 3 or 4 times.

//2000CAYukon