Strange clutch engagement

Joined
Nov 13, 2002
Messages
199
Location
Michigan
Hello, I wanted to hear the opinions from the more experienced drivers than myself. I have a new Subaru with a 5sp manual with less than 6k on the odo. I’ve noticed recently that the clutch pedal feeling has changed noticeably in the following ways: When the car is cold such as when I get in to drive to work in the morning the clutch is easy to depress and clutch engagement is close to the floor just as I remember it when it was brand new. As the engine warms up the clutch pedal becomes much harder to depress and what little free-play was available has disappeared. It’s at this point the clutch doesn’t fully engage until the pedal is completely let out. The clutch sort of acts like an on/off switch and makes it difficult to accelerate smoothly from a dead stop. I’ve spent hours researching what might explain this behavior and I also bled the hydraulic system according to the procedure outlined in the factory service manual with no change. The only thing I can think of is the spring plate within the pressure plate is changing its resistance (spring back force) with temperature and the “fingers” are pushing back against the throw out bearing in turn causing the release force to push back against the slave cylinder piston. Does this make sense? I’ve never experienced this “variable engagement” before on any manual trans vehicles I have owned and wasn’t sure if my theory made sense. Has anyone else experienced something like this before? Funny thing is I found a few internet posts at random forums where people complain of similar behavior but no one ever responded to them. I guess it’s one of those rare things?? Any input would be greatly appreciated!
 
Last edited:
Joined
Dec 30, 2006
Messages
25,647
Location
Dallas,Tx USA
Sounds like the clutch fluid is expanding when its heating up. The same thing happened to me when I had my clutch pedal adjusted with not enough cold free play. When it would get hot,the fluid expanded and the clutch would *almost* slip. I added a lil more pedal-play to it and it`s now right on the money.
 

HondaRD

Thread starter
Joined
Nov 13, 2002
Messages
199
Location
Michigan
Thanks for the input. I thought about that to so I did adjust the pedal out a bit to get more free play but all it seemed to do it increase the overall stroke of the pedal since all free play gained is taken up once the engine has warmed up. I also adjusted the push rod to the master cylinder to reduce pedal stroke but I cannot adjust any more since clutch engagement when cold is just above the floor. I may have to try and convince the dealer there is something amiss and hope they will agree to replace the clutch under warranty but I'm pretty sure they will tell me it is normal.
 
Joined
Sep 5, 2006
Messages
19,479
Location
Chicago Area
Apparently you have a standard system , not a fly by wire clutch. Get something from the dealer in writing. Make noise at them. This is un acceptable. If there is no service bulletin now, there may be in the future.
 
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