Ok you guys, what do you think of this?
1991 RS Camaro (in the UK-by the way) with rebuilt (1000 miles) 350 out of a 1977 pick up, and used T5. Brand new flywheel, pilot bush, clutch friction plate, pressure plate, throw out bearing and slave cylinder. When the clutch is pressed down, a “moan/groan” comes from the bellhousing area. Not every time, but it can be started by revving the engine (clutch down still). The noise sounds just like a shaft rattling around in a bearing. The type of noise that you get when the starter motor bush right at the front is worn and the shaft vibrates inside it when the engine starts and the starter disengages. When the clutch is brought back up in neutral, the noise stops. When it is brought up to biting point in any gear the noise stops.
I pulled the trans and the clutch, inspected the pilot (ok), renewed the throwout bearing anyway, inspected all clutch components and input shaft. All seemed okay. Put it all back and guess what? Same noise!
Just now-started it up from cold, idles very nicely, thank you (!) and pressed the clutch pedal. No noise. Revved the engine-noise started. Kept clutch down all the time. Moaning/groaning coming and going. Clutch up, noise gone. The vibration can be felt through the release fork and gear lever when it occurs. It is loud under the car.
First I thought that the input shaft bearings on the T5 are wearing, but when the clutch is down, and the input shaft is not spinning, the noise is there.
Any ideas before I pull it out again! I’m getting quite good at this trans pulling bit!

I’m going to nip it over to the shop that built the engine for me tomorrow for them to have a listen. I will still do the work, but I want an opinion. Typical. Just as the show season starts! First one on Saturday!

Thanks for any replies.
Andy.

 

It sounds like the same thing I had going, sounds like the throw out bearing rubbing against the pressure plate. i really don't know what to tell you, is this a stock clutch and pressure plate your throwing in, is the PP tourqued down to spec? Check the throw out bearing for finger wear from the PP. Also check your clutch fork and be sure it is aligned correctly. Sorry, all i can think of, hope you find it.

 

This may sound odd but I have changed a couple of throw out bearings with simmilar simptoms all of them were Plastic composit throwout bearings. I changed them over to a heavy duty steal bearing and never heard a noise again. Another thing it could be is the slave cylender not engaging disengaging.
Hope that helps
Dan