Clutch noise, or is it the gearbox?

adamskibx · Post by **adamskibx** » 04 Aug 2006, 00:19

Hello all. Its a while since ive posted on here. Im having trouble diagnosing a grinding/wooshing sound from my clutch or gearbox. I thought it sounded like a dry and worn clutch release bearing, but the symptoms seem more complex than that. The sound is most obvious when in lower gears at around 2500 RPM while either maintaining a constant speed or declerating. However, I can make the car make this sound when its parked too, so I have ruled out the differential end of the gearbox. It does it in any gear with the clutch pressed and doing between 2300 and 3000 RPM, almost as though something is resonating. Its a boomy wooshing/grinding sound, and is directly proportional to engine speed. It wont make this sound when in neutral however, no matter what you do with the clutch.

Im replacing the whole clutch soon, but I have a spare gearbox. The car is a Mk1 BX19 GT and so it has reverse by first unlike the spare gearbox I have, so im hoping its the clutch bearing or something. One other posibility I suppose is the crankshaft end bearing?

Has anyone come accross this problem before? Cheers, Adam

AndersDK · Post by **AndersDK** » 04 Aug 2006, 02:05

That noise is to your description not related to release bearing or the RHS axle support bearing.
Must be something resonating at exactly that engine rpm.
As it is an elderly petrol lady - I would first go for a shivering warm air intake shield at the exhaust manifold. Known to make a very mysterious and nasty noise when it starts rust away on the bolt holes.

You may find you still have a noise - but now different - when the shield has been fixed. Common with multi problems on old BX'es

alan s · Post by **alan s** » 04 Aug 2006, 02:48

Checked the oil level in the gearbox?

Alan S

citronut · Post by **citronut** » 04 Aug 2006, 08:48

check yiour lower engine staberliser bush,as this can make arealy horible noise,or is this a rotating noise you are getting
regards malcolm

adamskibx · Post by **adamskibx** » 04 Aug 2006, 10:39

Thanks all. It appears to be a rotating noise. However I will check the heat sheild. The oil level in the gearbox is correct as I refilled it with the correct quantity when I changed it. Malcom. I will chech the lower engine stabaliser. It is a rotating sound but I suppose if there was intermitant failuture of the rubber here any rotation sound would be transfered into the body of the car.

goldfinche · Post by **goldfinche** » 04 Aug 2006, 11:46

Hi when you do the clutch check to see how much play there is in the first motion shaft and how it feels when rotated. That's the shaft that goes through the clutch centre plate. it could be the bearing worn. This can happen through natural wear but also if the weight of the g/box has been taken by the shaft when fitted or removed. While you are there it would pay you to have a look at the bearing in the end of the crankshaft. Sometimes they are worn almost to the point of not being there anymore.
Cheers.
Geoff.

Post by **Peter.N.** » 04 Aug 2006, 11:49

.... otherwise sounds like a noisy 1st motion or layshaft bearing.

adamskibx · Post by **adamskibx** » 10 Aug 2006, 00:10

Cheers guys. I feel like a complete plonka because I did let the weight fall on the shaft for a second when I was putting the box in. I hadnt thought of that:-( Oh well, ill know not to do that next time!! It was a reall struggle as it was just me on my own, lifting the gearbox by putting one arm through the battery support tray and the other near where the starter motor joins on. I should have just hired an engine crane really. Thats what ill do this time round.

Post by **Peter.N.** » 10 Aug 2006, 09:37

.... Or put a jack underneath.

mezuk04 · Post by **mezuk04** » 10 Aug 2006, 09:39

Ow, that thought popped into my mind...I'm rather clever when I say nothing.

French Car Forum

Clutch noise, or is it the gearbox?

Clutch noise, or is it the gearbox?

Noise.