Clutch Release Bearing Squealing!

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Conrad Carter
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Clutch Release Bearing Squealing!

#1 Post by Conrad Carter »

Just installed original engine back in my 63 Coupe. Of course, there is a problem. Clutch Bearing is squealing when I let clutch engage. So, question is, should I remove engine and install new bearing or should I drive it some to see if bearing quietness itself? I have no idea if bearing was squealing when engine was removed some 10 years ago since I did not own car then. Is there a downside to driving car as is?
Conrad

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marcsherriff
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Re: Clutch Release Bearing Squealing!

#2 Post by marcsherriff »

Conrad, mine was similar. I put up with it for months, driving most weekends. Never quietened down.
Gave me the kick in the pants to drop engine, and do the rebuild I had been planning for a couple for years, and replaced the whole clutch assembly.
That fixed it!
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Alan Hall
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Re: Clutch Release Bearing Squealing!

#3 Post by Alan Hall »

Probably not the release bearing but lack of lube on the transmission input shaft where it enters the gland nut. A finger full of Bosch distributer grease mixed with powdered graphite smeared in the gland nut is what I use, others may have their choice. Does require dropping the engine though.

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Harold Singh
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Re: Clutch Release Bearing Squealing!

#4 Post by Harold Singh »

Alan Hall wrote:Probably not the release bearing but lack of lube on the transmission input shaft where it enters the gland nut. A finger full of Bosch distributer grease mixed with powdered graphite smeared in the gland nut is what I use, others may have their choice. Does require dropping the engine though.

I had a high pitch hum when I put my engine back last time. Sounded like the trans. I wonder if the same happened to mine. Will bearing grease work on the trans input shaft? What are the other blends or concoctions people use?
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David Jones
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Re: Clutch Release Bearing Squealing!

#5 Post by David Jones »

I would go for the TO bearing especially if it has been sitting around for years. The lighter fractions of the grease will have evaporated and by now the heavier portions will be oxidized. The bushing in the gland nut is not under any stress and is usually rotating with the first motion shaft and does not make very much noise even when dry and in the case of the phosphor bronze early versions is self lubricating to some extent due to its metallurgy. Pull the engine and change the bearing for peace of mind.
You can diagnose between TO Bearing and gland nut by just pushing in the clutch and then releasing it without putting the car in gear and moving. Before you put the clutch in, the first motion shaft is spinning with the engine so there is no relative difference in speed between gland nut bearing and shaft. The shaft will slow down as the clutch is disengaged but all that is slowing it down is the viscosity of the oil in the trans. When you select a gear and before you start to move the action of engaging a gear will stop the first motion shaft spinning so it is now stopped in relation to the flywheel/gland nut. This is when it would squeal if it were seizing up not as you release the clutch.
If I am wrong in this description of the action of the first motion shaft I am sure Vic will correct me and I would be happy to be corrected.
If I had known I would live this long I would have pushed the envelope a little harder.
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Harold Singh
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Re: Clutch Release Bearing Squealing! Vic?

#6 Post by Harold Singh »

Conrad I hope we can narrow it down for both of us!

I happened to order a TO bearing as a just in case as you mentioned David. I also wonder if Vic could chime in on his thoughts on diagnosing the TO bearing versus the gland nut as you mention.
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John Lindstrom
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Re: Clutch Release Bearing Squealing!

#7 Post by John Lindstrom »

I put the wrong clutch disc on once and it was grinding on the pressure plate when I engaged the clutch, sounded like there was rocks inside the transmission. Had to change my underwear afterwards.

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Re: Clutch Release Bearing Squealing!

#8 Post by Dick Weiss »

The original gland nut had a bronze bushing w/internal grooves to retain initial grease.
Later gland nuts had/has the needle bearing (like in VW's) which will eventually get noisy if the initial grease gets lost over time.

If not changed, it could get jammed and possible surface damage to the mainshaft's hard surface/diameter.

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Martin Benade
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Re: Clutch Release Bearing Squealing!

#9 Post by Martin Benade »

If that gets jammed it acts just like a dragging clutch, grinding while shifting into reverse.
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Vic Skirmants
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Re: Clutch Release Bearing Squealing!

#10 Post by Vic Skirmants »

TO bearing; period. David, great explanation.

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Re: Clutch Release Bearing Squealing!

#11 Post by Martin Bruechle »

Hey Vic, I bet you've seen where a guy will drill a hole in the bell housing and squirt some oil on it ?
Saw some VW's like that. Probably when trying to sell a car, quick Mickey Mouse fix.

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Re: Clutch Release Bearing Squealing!

#12 Post by Conrad Carter »

To clairify symptom...squealing only when car is in gear and I start to engage clutch. Car is silent when engine is running and trans in neutral. Also silent if in gear and clutch pedal is on the floor.

Conrad Carter
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Re: Clutch Release Bearing Squealing!

#13 Post by Conrad Carter »

Follow up question. Will I hurt anything if I drive it, squeal and all?
Conrad

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David Jones
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Re: Clutch Release Bearing Squealing!

#14 Post by David Jones »

Chances are that the TO bearing is starting to seize so what will happen is that it will start wearing down the fingers of the pressure plate. Look at the pictures and read the thread on Harold Singh's clutch on TO bearing and clutch in the last few days.
If I had known I would live this long I would have pushed the envelope a little harder.
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GregVandenbussche
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Re: Clutch Release Bearing Squealing!

#15 Post by GregVandenbussche »

Might want to update to 901 TO bearing, smoother clutch, no more broken cables..
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