Ok so I posted this once before but wasn't able to find an answer to fix the problem so im trying it again. The problem is that once the car is warmed up and sitting at idle it makes this high pitched squealing noise. It sounds like its coming from the belt but ive sprayed belt lubrication on it and it didn't change the sound at all. The weird thing is that it only does it while at idle and warmed up. While in park it does it the whole time but once in drive and driving down the road once you hit 20 mph the noise stops. Any help/advice is greatly appreciated

 

ok i just listened to that sound file and wow is that annoying lol..I would check the bearings in the idler pulley , alt, and power steering pump.. Im leaning towards idler pulley bearings..I can almost hear a metal sound scraping seems to be bearing noise to me..The bearings are sealed for life so when you spray the belt it is not getting to the rollers in the bearing hence the reason its not stopping..This is of course assuming everything else is working as it should like shifting etc..

 

yea I can assure you that the sound is very annoying lol. I didn't even think about those things being sealed like that, next time I drive it I will try spraying some lube directly on/in that pulley and see if that makes a difference at all if so then I'll try replacing it.

 

Take a long screwdriver - place plastic handle end in ear, place other end at component (like idler pulley, water pump pulley, smog pump pulley, etc.) and listen - the screwdriver will act like a stethescope and pass the vibrations directly to your ear drum, and you'll be able to tell exactly what's making the noise.

BE CAREFUL!!! I don't want to hear about your dumb a$$ losing an ear, getting your tie caught in the belt and choking to death, etc.

 

lol@ Newbie...He is correct on the screwdriver trick it works great..Another thing is you could remove the belt and check all the pulleys for play then free spin them slowly feeling for it to catch on rotation..The catch will be a bad roller in the bearing ..

 

Thank you both for the advice I will try all of these things out tomorrow and see what I can figure out and let you guys know what the problem was, and don't worry newbie I'll be sure to take my tie off ahead of time lol

 

ok so I did the screwdriver trick but im still not sure where its coming from. I checked all the top pulleys. When I put it to the tensioner pulley I heard a little noise, but when I put it to the alternator I heard a bunch of noise which would mean its the alternator causing it right? but thats brand new so i don't see how. My next question is how do i go about seeing if the belt is straight cause when the cars running it almost looks like the balancer is wobbling.

 

Glad to hear you didn't loose an ear!

All motors that I've ever seen have a tiny bit of 'wobble' in the balancer. You should be able to 'bend' the belt by pushing with your thumb, but no more than about 1/2 - 3/4 inches deflection (wow - I used a big word!). But - you are serpentine, only one belt - the tensioner pulley does all the adjustment for you!

Just because the alternator is "new" doesn't mean it's good - I've bought plenty of "new" that was bad. If you heard any grinding-type noises with the screwdriver that sound louder than any of the other pulley's "grinding" noises, then I'd say that component is the one. If the alternator is new, yank it off and take it back - tell them it squeals, and have them replace it - they usually have a limited lifetime warranty. Find that receipt for sure.

If it still has the issue then I'd try replacing the idler pulley next. It's cheap and easy, and won't hurt anything.

 

yes just checked and both my ears are still intact lol.

Ok I wasn't sure about the wobble, but like I said the tensioner pulley has a little noise to it but the noise coming from the alternator is the squelling noise just not as loud. I still have the receipt so I will try a replacement one and like you said if that doens't fix it then that will at least help narrow it down a little.

 

alternator was loud then thats ur prob,tens pully nade noise too kill 2 stones with one bird lol do them both at the same time u can get them both at jy for cheap

 

Ok well I went out today and took my belt off and turned the alternator pulley by hand and it didn't make a sound. Im thinking that the noise may not be from the belt it almost sounds like its coming from the water pump. It seems like its not a belt because the noise continues after I shut the car off. Like after the belt stops the noise is still there for a little bit, so im not sure what it is

 

dang is that annoying. It's mechanical. Do you still have that silly smog pump on your car? It might be that.

It sounds like the giant ants from the movie 'Them"

http://www.youtube.com/watch?v=mBHaM...eature=related

 

OK well im a complete newb at cars so if you describe what the smog pump looks like I may be able to tell if I have one or not lol. but your right it sounds exactly like those lol

 

If the noise is still there for a few seconds after the belt stops moving then i would look HARD at my fans be it electric or belt driven..The fan motor has bearings in it as well.Now im thinking thats why it does it after the car has warmed up..Because the fans are kicking on..If its a belt driven fan grab the fan amd rock it back and forth if it moves the hub bearings are probably shot..

 

My fan temp sender is for 240 which seems to hot to me so I just turn it on manually, but originally I though it was the fan so I checked for the noise without turning the fan on at all and it still made the noise. The fan is electric by the way. To me the noise almost sounds like pressure building up from the water pump or something so I'm not sure

 

Your AC compressor and the SMOG pump (i believe) have a clutch-and-engage system inside, so the pulleys spin free when they're not active. It could be those. The noise you're getting off your alternator is probably off the carbon brushes inside. Smog pump should be the top pulley on your passenger side. AC compressor would be right beneath it. Maybe I'm mixing those up, but I dont think so.

Anyhow, try looking into those two. The aforementioned clutch systems tend to fail, sometimes. I've seen similar problems on an 01 Monte Carlo and a 98 Dodge Intrepid.

Second guess would be play in one of the pulleys. As mentioned above, remove belt and attempt to wiggle each on an axis perpendicular to the axis of spin of the pulley.

Doesn't sound like a fan problem.

Either way, I don't think it's much worse than annoying, so factor that in before you sink $$$ in it.

 

my engine is not the stock 305 its an older 350 so I don't think it has a smog pump because the top pulley on mine is the ac compressor. But I checked the pulley once before and didn't hear anything out of the ordinary. Like I said before it almost sounds like its coming from the water pump. It doesn't sound like the belt because the noise after I shut the engine off almost sounds like pressure releasing or something.

 

top pulley on my 89 305 is also the A/C. Underneath it is (actually was as it's gone) the smog pump.

 

While this really does sound mechanical, the fact that the sound dies off gradually, rather than stop immediately, when the engine stops, makes me wonder if its not a vacuum leak. Perhaps carb base gasket? Easy to check with a spray bottle of water, or any kind of aerosol liquid.

Try having a freind turn the car off while you watch the accessory drive. This may help you isolate the noise, if it is accessory drive. A mechanics stethiscope is cheap at your local auto parts store. The long probe and flexible hose reduce the chance of getting your ear whacked off or cathing the screwdriver in your belt. The stethiscope works well for finding noises, such as your water pump bearings. A WP bearing that loud should be loose when you wobble the pulley with the belt off.

 

Yea I've done the friend thing and it sounds to me like its right at the waterpump. The pulley did not seem loose when I checked it by hand though. I will check for a vacuum leak also though and see if maybe thats what it is.

 

I assume you checked for play in the pulley with the belt off. Also, a dry bearing may not yet exhibit runout, even though it's noisy. I hate to even bring this up but a damaged main or cam bearing sounds alot like this too. How is your oil pressure?

 

Yes, I pulled the belt to check the pulley, but the engine hasn't had more than 1000-2000 put on it since the new rebuild, so that shouldn't be the problem should it? I'm not sure on the oil pressure until I hook my new gauge up.

 

Oh sorry. If you'd said that, I didn't remember. It's unlikely that you would have a spun bearing at such low mileage unless there was an error made in the assembly. You would have metal fragments in the oil as well. Someone mentioned the AC compressor. The AC compressor clutch bearing can go bad and make this type of noise. You should be able to find that by spinning the pulley with the belt off. The smog pump is direct drive(no clutch) doesn't mean it couldn't have a dry brearing though.

I always start with my mechanics stethiscope and try to pinpoint the noise as close as possible. It can be hard because these noises transfer through the engine and can seem to come from all over. But you can narrow it down with the scope. Then pull the belt and try pulleys by hand to isolate the source.

 

No I hadn't previously said that so your fine. The oil looks fine and I feel pretty confidient that the assembly was done right so there shouldn't be any problems there. I don't have a mechanics stethiscope yet. I think I may invest in one of those because they sound like they come in handy. So as soon as I look into that I will get back with you.

thank you so much for all your help so far.

 

Look for the stethiscope at any parts store. They are faily cheap. I paid $15 for mine(Performance Tool) 12 years ago at Baxter's in Portland, after loosing my Snap On unit. Ive used the hell out of it and it still works great.

 

Sorry I haven't gotten back to you sooner, the weather hasn't been the best lately so I haven't been able to work on it. Now it seems I have bigger problems because im not getting any fuel to the engine so I think I may have a bad fuel pump, or relay. Once it gets nicer out I will try the stethoscope though and let you know my findings there.