I've noticed a weird noise coming from my belt. It seems to be around the alternator. It's pretty quiet at idle, but when I rev it the noise gets louder. However, if I spray some wd-40 on the underside of the belt wrapping around the alt's pulley, it goes away for about 10-15 min then it slowly comes back. Bearing, worn belt, rock, or somthing in the pulley?

 

Probably the idler pulley bearing. Put a large screw driver directly on the center bolt while the engine is running and the other end against your ear. You'll hear the bearing making noises if it is bad. Be very careful not to touch any moving parts!

It only costs about 10 - 20 bucks. You can buy just the pulley with bearing or the entire spring assembly with pulley. Either are readily available anywhere.

Spray WD40 right in the pulley center to see if quites the bearing. If it does, you know it is bad. Don't get it onthe belt or it will slip.

 

Okay I gave that a shot and the bearing sounded fine. I'm starting to think that it's the alternator pulley's bearing starting to go. I appreciate the advice though at least that was narrowed out.

 

Yes, it definitely sounds like an idler pulley bearing going south. Get it fixed before it seizes.

 

USe the same trick with a scredriver on the alternator to hear if the bearing is making sound. You can also remove the belt and spin it by hand to see if it feels right or makes noise.

 

Yeah I tried that on the alt too but that sounded fine. I'll have to take it to the shop one of these days and see if they can do a quick diagnosis. Thanks for the help guys I'll let you know what's up.

 

why go to a shop man?

go to the parts store and buy a new belt tensioner pulley, or the whole assembly, because its probably on its way out too. Then get under your car, put a 13mm on the belt tensioner pulley, turn clock wise. That will relieve tension. Take the belt off and then you can let go of the 13mm. Then you need a 10mm, theirs 2 bolts, 1 on each side of the tensioner. Take them out, the belt tensioner should now be free. Then just replace with your new one, make sure to lock tight the bolts.

If you just replace the pulley, leave the tensioner on the car unless you have air tools, and just take the center bolt out and then replace with your new pulley.

its a 15 minute job, 30 for a first timer.

 

Yeah I could do that myself, I just wanted to see what they say. But after thinking about it, there is a good chance it's just the belt cuz when I spray a bit of wd40 on the belt, the squeak goes away instantly. I'll pick up a gatorback and put it on and I'll let you know if that fixes it.

 

I had the same problem, no matter what belt I used, until I picked up a gatorback. I hope that fixes your problem!

 

Wow, there are 6 parts stores around me and none of them sell gatorbacks. Is there any other belt that works good?

 

Replaced the belt with a Gates and the noise is gone.