SOLVED: 1991 318iS - Grinding noise when push clutch to the floor

[jsnppp]

1991 318iS w/ M42 and Getrag 240 5 speed

Backstory - I just replaced the clutch (and pressure plate, throwout bearing, pinion bearing) while I resealed the transmission and replaced rear main seal.

Car shifted well before the update.

Put everything back together and now when I push the clutch all the way to the floor, at maybe 1/4 to 1/2 inch from the floor I hear a grinding noise, like something spinning and hitting something else. Car is in neutral.

To my mind, it's like the clutch slave is pushing a bit too far.

I did not change the clutch slave, however when I was bleeding it I hyper-extended it a bit and had to push the piston/rod back in.

I found this link, feels similar: https://www.bimmerforums.com/forum/s...slave-cylinder, but I find it hard to think the rod is now too long.

The clutch seems to work fine otherwise. No odd noises, etc. I haven't driven the car but just lightly let the clutch out while idling in garage.

Any thoughts? I hate to put washers in or cut the rod back.

[monty23psk]

Was anything down with the flywheel?

[jsnppp]

It has a stock dual mass flywheel, I didn't modify it as the surface was good and I didn't have trouble shifting or clatter beforehand. My main purpose for opening it up was to reseal transmission and replace rear main seal...

Somethings up for sure.

Jason

[e30austin]

i've seen this a couple times; in both instances, the last person to have the transmission off, did not install the release bearing correctly. it was installed 90 degrees off, so when the clutch pedal was depressed completely, it was allowing the clutch release arm to contact the pressure plate. oddly enough, both times i saw it, it was on M42 powered cars.

[jsnppp]

Oh boy, really! This feels like the right answer.

Since I am the one who pulled the transmission, I get only myself to blame.

Question: I am pretty sure that I installed the throw out bearing like this photo (not my car or photo). Does the throwout need to be 90 degrees from this? Or is this correct?

IIRC, I don't see how the throw out bearing could be 90 degrees off. Would be nice to explore it w/o removing... I have a camera scope and may try peering through the clutch slave opening.



Good times.

[jsnppp]

UPDATE - I crawled underneath and found the spring retainer on the other side of the clutch release arm was not properly installed. The topmost clip was not engaged.

I reinstalled it using pliers and a hook.

This helped a lot. With the car in neutral and running, I can now push the clutch in to the stop and not have grind/noise.

However, if I remove the clutch stop entirely it can still do it. When I have it adjusted just so that the clutch stop prevents the noise from happening, the clutch engagement is very near to the clutch stop.

Does this sound right? I guess my question is - with a properly installed system, should I ever be able to have a grind/noise from too much clutch travel? I'm thinking not...

I'm trying not to have to take it all apart again..

~Jason

[jsnppp]

SOLVED: Took about an hour to separate the transmission from the block. Took another hour to get it far enough back to be able to see inside. That metal gasket hung up and killed some time.

This is what I found:



As you can see the throw out was indeed 90 degrees off, allowing it to sit further in the carrier arm and thus letting the carrier arm hit the pressure plate.

Took another 2 hours to put it back together, the stupidest things slowed me down.

Truth be told, I can still make the grinding noise but only iff the clutch stop is removed and the clutch pedal allowed to hit the literal floor. With the stop in place, even at lowest position, no grind.

~Jason

[82eye]

good catch

[jsnppp]

Thanks! e30austin steered me in the right direction.