High pitched squeaking from belt drive...agh!

[ghunt]

I posted last week about my idler pulley siezing up.

Prior to that there had been some occasional squeaking from the belt drive but it wasn't too bad. I wasn't sure what was causing it. A couple weeks after that the idler locked up, so I replaced it. While in there I checked out the tensioner pulley as well and it looked like the bearings were about shot on it too. Wasn't sure if I could trust it, so I put the tensioner pulley from my Thunderbird on it its place and put the new tensioner on. I have not yet installed a new serpentine belt, but plan to when I get the new tensioner pulley.

Anyway, ever since I did that, it has been squeaking/squealing worse than ever. I'm talking about it being at the point where if you're standing in front of the truck with the hood open, it just about hurts your ears it's so bad.

I seriously cannot figure out why it's making this noise and why it won't go away. The tensioner pulley from my Thunderbird seemed to be nice and tight. I'm fairly certain it's not squeaking because of the belt slipping, because it does it at idle. It also seems like it doesn't really start doing it until the truck's been running for a few minutes.

I'd really like it if the new tensioner pulley and new belt fixed it, but I have a feeling it won't. Any ideas, what should I be looking at?

 

[jiggiwdit]

Bearing in water pump.

 

[geonc]

Any ideas, what should I be looking at?

Just at idle---or mid eng speed? Only cold or all time?
Vac pump,P/S pump.....How is the belt tracking on the idler pulleys?
What condition is the smooth side [non-ribbed] of the belt from contact with the idlers?

Got an older belt?---put it on and see if it changes/goes away......

 

[fx4wannabe]

Could be any of the pulleys. Get a long handle screw driver and with the engine turning put it on the accessories one by one and put you ear to it. This should help you isolate it.

 

[ghunt]

To answer the questions-it seems to do it all the time. It's relatively quiet at startup, and by the time I get home it's very loud.

As for the tracking, it seems to be fine though I noticed it's running at the outside edge of the idler pulley. Smooth side of the belt looked fine.

I put a new tensioner on it tonight (as a side note- have any of you guys tried to replace the pulley for the hydraulic tensioner? Advance Auto Parts showed 1 in their system at a store 45 minutes away. I ended up using the one that was shown as being for the 8-rib belt, it fit like it was supposed to go on there and was the same width as the old tensioner pulley, just slightly larger in diameter and made of steel instead of plastic. Was cheaper too ), and a new belt, and started it up and it didn't seem to be making any noise. Guess I'll wait and make sure it's ok tomorrow when I drive to work.

Funny thing is, the sound my truck has been making is almost identical to what a co-worker's F150 with a 302 in it sounds like (same bodystyle as mine, not sure what year)

 

[Agnem]

Your exisiting belt has worn to the shape of the pulleys you had. I wouldn't expect anything should be done until you put a new belt on there.