C3 corvette. Squealing noise.
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Instructor
Joined: Jan 2017
Posts: 175
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C3 corvette. Squealing noise.
My 1974 corvette has a squealing noise coming from the engine bay.
1. The high-pitched squealing happens only when accelerating.
2. The power steering pulley and pump were both replaced a few years ago. The belt was reused. (the noise began after that)
3. I have noticed when the engine is idling the power steering pulley has significant play in it. ( the pulley motion im describing moves in and out, like movement towards the radiator and back rapidly)
Is there any way to tighten up the pulley or do I have to reinstall a whole new pump/pulley?
1. The high-pitched squealing happens only when accelerating.
2. The power steering pulley and pump were both replaced a few years ago. The belt was reused. (the noise began after that)
3. I have noticed when the engine is idling the power steering pulley has significant play in it. ( the pulley motion im describing moves in and out, like movement towards the radiator and back rapidly)
Is there any way to tighten up the pulley or do I have to reinstall a whole new pump/pulley?
Le Mans Master
Joined: Oct 2000
Posts: 6,362
Likes: 30
From: Oak Harbor WA
From what you are describing I would be under the impression that the pulley is suffering from one of three things:
Pulley is crocked itself.
Pulley installed slightly off center.
The pump shaft is no longer straight.
Besides the noise this could lead to a thrown or broken belt. The squealing is likely belt slippage.
I'll assume from your description that you are not trying to maintain the car to 'NCRS' specs which is why the pump/pulley were replaced and not rebuilt... could be the newer unit came with a defect.
You could remove it and then check the shaft runout to see if that is the problem or if it might be just the pulley. Once you figure that mystery out then replace the belt when doing the reinstall.
Pulley is crocked itself.
Pulley installed slightly off center.
The pump shaft is no longer straight.
Besides the noise this could lead to a thrown or broken belt. The squealing is likely belt slippage.
I'll assume from your description that you are not trying to maintain the car to 'NCRS' specs which is why the pump/pulley were replaced and not rebuilt... could be the newer unit came with a defect.
You could remove it and then check the shaft runout to see if that is the problem or if it might be just the pulley. Once you figure that mystery out then replace the belt when doing the reinstall.
Is my vette stock?? HAHA
Joined: Oct 2015
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From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
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Tighten your belts, one at a time starting the engine after each belt to see which one it is. If it changes pitch then that’s the belt. Before you tighten the power steering shaft, while the belt is loose, pull on the pulley, if it’s loose, tighten it, if the shaft slides in and out, it needs rebuilding or replacing. If the pulley is just warped, tighten the belt and check your results. Sometimes old belts get a shine on them which belt dressing can cure, or the belt just needs replacing even though it isn’t cracked
