please help with squeal/chirp
Thread Starter
Intermediate
Joined: Nov 2000
Posts: 45
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please help with squeal/chirp
I have an 86 coupe with iron heads about 17k miles. Mods: air foil, de-screened MAS, smooth bellows, home ported top plenum, air pump eliminator, AFPR, relocated MAT, borla mufflers, and SLP cold air. While in park/neutral, I hear a short duration high frequency chirp/squeal off idle that lasts maybe 1/10 of a second. This happens when I rev up and coast down maybe around 1000 RPM. I changed the belt, new alternator, and new dampener. With the belt off I rotated each pulley and I don't hear a squeal - I know things may be different when unloaded. I brake raced the engine and the engine mounts seem fine. The sound is too high of a frequency to get a good bead on it. It always sounds like it is coming from somewhere between the front of the engine and the radiator and somewhat low and always from the other side than I am. I used an aluminum rod to jiggle the tensionor while the car was running and I couldn't make the noise appear. I used the same piece of AL to wiggle the exhaust from the engine compartment and under the car and I couldn't make the chirp happen. I thinking about getting a tensioner and idler pulley next. Any suggestions?
Le Mans Master
Joined: Jun 2002
Posts: 6,097
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From: High Plains Drifter Fayetteville, AR
Re: please help with squeal/chirp (zzz)
Take the serpentine belt off and run the engine for a few minutes to see if the sound is still there. If it is, it's most likely coming from somewhere else. If it isn't there with the belt off, at least you have isolated it to the accessories. :cheers:
Safety Car
Joined: Feb 2002
Posts: 4,212
Likes: 10
From: Sun City West Az
Re: please help with squeal/chirp (1989redvette)
While at idle, use an old candlestick and let the belt travel over it. The wax will stop any squeeling from the belt itself if it's slipping. Only lasts a short time so take it out right away and try it.
Thread Starter
Intermediate
Joined: Nov 2000
Posts: 45
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Re: please help with squeal/chirp (zzz)
OK - no belt = no squeak. I guess that rules out the engine mounts. I put a new tensioner pulley on and it still sqeaks. I loaded and unloaded the tensioner and it still sqeaks. The belt is new. I didn't have a candle but I sprayed a mist of water as the belt went over each pulley and still got the squeak. I cycled the AC and still squeaking (more pronounced as the RPMs increase and decrease with the compressor cycling. The car stays relatively cool so the water pump internals seem OK - maybe a bad outer bearing (if there is one). When I move the steering wheel I don't hear any noticable change in the squeak. Maybe a bad power steering pump bearing? Any other thoughts?
Le Mans Master
Joined: May 2003
Posts: 5,203
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From: Las Vegas Nevada
Re: please help with squeal/chirp (zzz)
I got the same cricket in my engine......I think its either the water pump or the air pump....cant isolate it though :crazy: It drives my wife :crazy: But I am so damn deaf from working on Jet engines that I only hear it once in a while. :skep:
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Safety Car
Joined: Feb 2002
Posts: 4,212
Likes: 10
From: Sun City West Az
Re: please help with squeal/chirp (JCAIRE2)
If you have an air wratchet, you could remove the belt and spin up those accessories with nuts...ie: alternator....listening for the noise. just a thought.
Safety Car
Joined: Feb 2002
Posts: 4,212
Likes: 10
From: Sun City West Az
Re: please help with squeal/chirp (Southern Comfort)
I think the noise from the air ratchet would drown out any other sounds....JMHO
Pro
Joined: Jun 2003
Posts: 559
Likes: 6
From: OKC OK
Re: please help with squeal/chirp (zzz)
I had a similar noise issue...water pump. I thought it was power steering at first too...toped it up but still ahd the noise...
Replaced the water pump and the noise is gone... replacing the water pump is a good time to replace the timing set, and clean between the radiator and condensor and be sure to straighten any bent fins. By far the longest part of the job! :seeya
Replaced the water pump and the noise is gone... replacing the water pump is a good time to replace the timing set, and clean between the radiator and condensor and be sure to straighten any bent fins. By far the longest part of the job! :seeya
Thread Starter
Intermediate
Joined: Nov 2000
Posts: 45
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Re: please help with squeal/chirp (MtlSphere)
I'm leaning toward the water pump too. The air pump is gone. I was thinking about squirting some oil into the weep hole in the water pump - I don't know though.
