Hello Everyone,

This is long. I'm sorry but I've already tried to narrow this down and hit a dead end. All information is relevant.

I have a 2006 R53 Factory JCW car with 68,XXX miles on it. As far as I know and can find in the limited records I got with the car, the clutch is the original. Up until yesterday the clutch began to engage around 1/4-1/3 of it's pedal travel from the floor and had a "normal" bite.

Yesterday I encountered a problem and I've done my research on it to a point where I've hit a dead end. I'm looking for guru input before I pull the transmission out.

Here's the details... I'm sorry it's long.

Yesterday I started the car after it had been sitting for about 30 minutes, so the vehicle was still hot from previous operation. I began to drive and about a 1/2 mile down the road there was a scraping sound that occurred right after I had shifted and no longer had my foot on the clutch pedal. It lasted for maybe 2 seconds and went away. It was loud enough that I could hear it moving at about 25mph with the windows down but by the time I recognized and reacted to it, it was gone. The next shift my clutch engagement is on the floor. It makes the sound again, exactly as before but that is the last time it has made any unusual noises.

I pull into a parking lot and fiddle with it. I can shift without too much trouble, but the clutch engagement is literally as soon as I left any pressure off the pedal. The friction zone is small and aggressive, the first couple times I bucked the car a little bit. The friction zone almost feels like a race clutch engagement. Very little warning before it bites.

So I drive it straight home using the clutch as little as possible. It makes no other strange noises and there are no additional changes in operation. It's almost like a setting was just changed...

So here's what I have found so far.

1. The clutch it not slipping.

2. The clutch hydraulics appear to be in excellent shape. The master and slave are both done dry under their boots. The reservoir is near the max line. I compressed the slave and bled a small amount of brake fluid out of the slave, no bubbles. The fluid started black-ish and then became clear. This tells me that the hydraulics are not leaking, the old(er) brake fluid was the first to push out, followed by fresh stuff from up the line. I checked the clutch line down to the slave and found no leaks.

3. The clutch fork arm is in the correct position, angled towards the slave with pressure against a resting slave. I found a post by Helix that if the arm is angled away from the slave at rest it could be an indicator of a throw out bearing issue.

4. The slave fully extends and does not lose pressure. It pushes the clutch fork arm past a vertical position and holds it there. I put a brace on the clutch pedal and marked the fork arm position. No change after an hour.

5. There is a plastic groaning sound when you press and release the clutch, but you can only hear it when the car isn't running. It sounds like the plastic bushing the clutch fork arm rides on. Cannot verify that it didn't make this noise prior to this incident.

6. I currently have the clutch pedal held to the floor with a stick. I left it overnight and I'll check it when I get home from work. If it was a air bubble in the line, gravity should work it out by this afternoon and we'll see if anything changes.


TL:DR - Clutch pedal engages on the floor, friction zone is small and has an aggressive bite. Made a less than 2 second scraping noise after the clutch had been completely released for two shifts when the change happened, no other noises to indicate issue. Hydraulics test out, clutch is not slipping.


So yeah, I have my thoughts on what the problem could be but I'm looking for some input. Not pulling the trans would be really nice. Not having any weird noises is causing a dead end because I've listened to enough clutch, TOB, and flywheel noises to last a lifetime.

 

Hopefully will get some responses. Please let us know on the air bubble possibility.

 

Appreciated.


I took the car out tonight, the clutch pedal being left pressed didn't change the feeling of the clutch. I was able to replicate the noise multiple times but it was only under full throttle pulling in second gear above 5,500rpm. Basically, highway on ramps. This is vastly different then when I heard it the first time.

It also sounds very, very similar to the noise found in this video, although the circumstances of the noise are different.

https://www.northamericanmotoring.co...tup-noise.html


However, I do have an oddball question to add...

Could coolant leak out of the thermostat housing, into the bell housing, and onto the clutch/flywheel? Have any of the shops ever encountered this? The thermostat housing is directly above the connection between the bell housing/trans/engine. The friction properties of the clutch could definitely be effected by coolant, you see where I'm going with this. Is this even possible? I don't know what the connection between the bell housing and engine looks like.


I feel like I'm going nuts because this wouldn't explain the change in the pedal engagement point but could explain my perceived change in the friction zone of the clutch.

 

Follow up post in case anyone stumbles upon this later. I hate finding a description of what I'm dealing with and then no resolution.

The end result was the throw out bearing was collapsing and the flywheel was beginning to go. The failures were causing a stiff pedal that felt normal to me because it was that way when I bought it. I'm also used to older trucks and cars with heavier clutch pedals. I never thought it was a symptom.

The throw out bearing never really made any consistent or loud noise but its failure was what changed my clutch engagement point. I drove it about 200 miles after my initial post and the clutch engagement point varied at random from "normal" to on the floor. I would get an intermittent scraping sound after the clutch was completely engaged as I posted before, but that was not often.

I had a new OEM clutch, flywheel, throw out bearing, and guide tube put in the car. I slammed the clutch pedal to the floor the first time I went to start it because the pedal is much lighter now.

So yeah, alternative facts for TOB failure that involved little to no noise.

Also, I highly recommend Helix in Philly!