Ladies and Gentlemen - I've got a 97 4-door, 4-wheel drive with the 4.3 (with A/C) and automatic transmission. My Blazer has just over 68K miles. I've got a very, very, very annoying squeak in the engine compartment. I know it's in the pulley system. I've already replaced the belt, the tension pulley and the idler pulley. I know it's almost impossible to diagnose through a message board, but I can't find it with what I've done so maybe y'all can throw me some suggestions. I can't isolate it with the engine running due to the space between the radiator and the accessories being tight (or my arm being too big) to put my diagnostic hose (cut off piece of water hose I use as a stethoscope). I took off the belt and turned each pulley by hand and the most I get a very slight squeak from the alternator. I'm got getting any leakage from the water pump so I've kind of put that piece on the back burner and I have no issues with the steering pump as far as dead spots or louder noise when the wheels are turned so that too is being put in the background.

Another problem I'm having is that it's not consistent or repeatable. I've tried to monitor it to see if it seemed worse during certain weather or temperature conditions, but it's not. The only constant is that it's always there - sometimes bad, sometimes not as bad but it's always there.

Any help would be fantastic as I'm now hearing chirps in my sleep!

Joe (macdaddy25177)

 

Yah I had a very similar noise I thought it was the alternator also since it made a squeak when spun by hand, but after changing it the squeak was still there. I put on a goodyear gatorback belt and it instantly disappeared. Now only if the rest of my trucks noises would go away I would be happy. What brand belt did you put on?

 

Thanks for the response.

The belt is a Dayco from NAPA. I've heard that I should turn the belt around. For the life of me, I didn't know those things were directional.

I did try putting soap on the back of the belt. All I got were soap flakes flying through the air and my son thought it had started snowing.

I very reluctant to try belt dressing on a brand new belt. What does belt dressing do anyway? Does it soften the belt or coat it or change the belt in anyway? I don't want to ruin a $40 belt.

 

It gums things up. I don't use it.

 

Just for kicks, remove the cap on the oil fill tube with the engine running. There was another member that had a similar noise that seemingly went away when he removed the fill cap. Source of the problem was a stuck closed PCV valve.

 

Dang! I never would have thought of doing that. I'll give that a go after work today. Thanks Kyle, I'll fill everybody in tomorrow. Same bat time, same bat channel (let's see if anybody here is old enough to remember that one!)

Joe

 

WHAM! POW!!

 

I to had a simluar noise in the engine bay it ended up being the oil dipstick was pushed to far down in the engine and was actually rubbing on the crank ever so slightly, when I pulled it out a little the noise went away, I figured the dipstick was a touch longer then it should have been maybe but I just dont force it in the tube tight anymore I just loosley insert it back into the engine now one of the stupied things I guess but it madea very anoying screaching sound. The other thing to do is just spray a little WD40 on the belt as its running instead of belt dressing which make a terrible mess, I have a bran new belt on and it to made a squeeking noise from time to time, I felt it just had to do with the moister in the air or something but when ever it happens I just spray a squirt of WD on it to shut it up worth a shot its better then having to spray that god awful belt dressing all over and make a huge mess.

 

Well guys and gals - I went out and tried the oil fill cap thing after work last night and nada. No change at all. BUT! While I was there I just kind of watched and listened and felt as the engine was running and I thought I had it nailed but was unsure until this morning. On my way out to start her up before taking the kids to school I brought out my nice new can of WD40 with the new permanently attached straw and hit the suspected offending object and KAPOW - no more squeak!

I was totally amazed that is was .... unbelievable .... the brand new tensioner pulley!

I was too busy trying to look for something else that I never suspected a new part could be bad. The WD40 wore off pretty quick so by the time I got to work the squeak was back. Since the dealer I bought this from actually purchased this piece and installed it, I don't have the receipt, but I think I can get it and arrange an exchange.

I'll check back in with the final result. But thanks to all who chimed in and gave me suggestions without making fun. I asked a friend the other day if they could lend an ear. I started her up and he looked at it - kind of cocked his head a bit and said "Well, it's something to do with your belt of one of the pulleys" and for some strange reason he took on the appearance of Homer Simpson. I felt like slapping him on the back of his head like Gibbs does DiNozoe on NCIS.

 

GIBBSLAP!!