Good job for the wife or girlfriend. Both, if you have them, but recommend not at the same time.
Squeal on Deceleration
Thread Starter
Instructor
Joined: Apr 2018
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From: Sabula Ia
Squeal on Deceleration
67 L79, manual trans. My hearing is not great but I am hearing a very high pitched squeal when I let off the gas. It continues until I load the engine, then stops. I am not sure what end of the car the squeal is coming from! I've listened with the hood up at idle, but can't hear it.
I need to get someone in the car to rev the motor while I listen with the hood up, but haven't had anyone around to do that last couple days. I am asking for other ideas or things to look for. My initial thoughts of possibilities are : belts, throw out bearing, U joint, I am leaning towards thinking its not belts because the noise stops when I accelerate.
Any thoughts are appreciated!
Steve
I need to get someone in the car to rev the motor while I listen with the hood up, but haven't had anyone around to do that last couple days. I am asking for other ideas or things to look for. My initial thoughts of possibilities are : belts, throw out bearing, U joint, I am leaning towards thinking its not belts because the noise stops when I accelerate.
Any thoughts are appreciated!
Steve
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Check your motor mounts and trans mount. Do you have PS? Look at the pulley for the pump and see how close it is to the frame. If the left motor mount is broken, it may be letting the left side of the engine settle lower and the pulley may be touching. Under load, it lifts and clears the contact spot. At the rear of the car, look at the pinion snubber/u-joint and see if it is rubbing on the body (it may not make a classic squeal). 
Dennis
Dennis
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From: Sabula Ia
Check your motor mounts and trans mount. Do you have PS? Look at the pulley for the pump and see how close it is to the frame. If the left motor mount is broken, it may be letting the left side of the engine settle lower and the pulley may be touching. Under load, it lifts and clears the contact spot. At the rear of the car, look at the pinion snubber/u-joint and see if it is rubbing on the body (it may not make a classic squeal). Dennis
Dennis
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From: Sabula Ia
If I rev it with belts on and it does not make the noise I would have to assume its in the driveline somewhere ----agree?
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if you rev it up with NO belts and it makes NO noise its either the belts OR barrings in the water pump or Alt
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From: Sabula Ia
Yeah, I guess I didn't explain it very well. I only hear the squeal when I'm in the car. That may be because if I'm running the throttle by hand the engine is too loud to hear it. I messed with it this weekend and found that it makes the noise pretty much all the time when the engine is cold, not just on deceleration. The car can be sitting still or moving, doesn't matter. It does quit however when the engine is put under a load. It also quits entirely after about 10 miles of driving. Since it squeals when not moving that eliminates anything behind the trans. I'm still leaning towards a throw out bearing but it squeals with clutch in or out. Also, I would think a belt would squeal regardless if it was cold or hot. Whatever it is it apparently expands enough when hot to stop squealing.