99 OBW Clutch linkage problem. Advice?

[AnotherGreenSubi]

I bought a used '99 2.5L 5-speed OBW in '01. My clutch pedal loses it's
ability to disengage the clutch as the car warms up. I suspect the master
cylinder in the hydraulic clutch linkage.

Within a year of purchase, I noticed a problem with the clutch pedal, but
more likely, a problem with the hydraulic linkage. The pedal does not
return all the way up to it's upper clutch-engaged position. Everything
operates correctly cold, but this condition develops as the car warms up and
the clutch is operated more. Consequently, I almost never experience this
condition in New England winters, but it develops very quickly on hot summer
days in stop/go traffic or city driving when I am shfting a lot. Not
suprisingly, I bought the car in
February, so I never would have caught it during the test drive. Hmmmmm.
At first, the pedal is just reluctant to pop back up over the over-center
position of the pedal return spring. Eventually, the condition degrades to
the point where I can not fully disengage the clutch and what action there
is occurs in the bottom 2-3" of travel and the pedal only returns about half
way. I doubt a worn clutch plate is the cause of this condition, but I'm
sure that it is an effect.

I suspect one of the hydraulic cylinders is leaking (by-passing). The fluid
becomes thinner as it warms up. Each time I operate the clutch, a little
more leaks arround the cylinder leaving less in the line between the
cylinders, until eventually, there is not enough left in the line to move
the clutch plate adequately. If unused for a while, the fluid is
eventually drawn back around the leaky cylinder by the clutch pedal
return-spring pulling on the master cylinder end.

I think it is the master cylinder attached to the pedal, and I am just about
to order one and try to replace it.

I have not ruled out air in the line or dirty fluid, nor have I pursued that
theory, but I have a hard time explaining this condition by air or fluid
condition.

Does anybody have any advice? Has anybody seen this condition.

Pete

 

[Henry Paul]

I had a problem similar to this on my 5-speed jeep. It would do the same
thing, except it would leak in the winter and not in the summer. Go figure.

If you have a hydraulic clutch, you have both a master and a slave cylinder.
The condition you have described is possible, fluid can leak past the seal
and the clutch will not disengage, alternately, the fluid can leak past the
cylinder altogether and drip out on the ground.

Inspect the area where the master cylinder meets with the firewall on both
sides. See if you can see fluid leaking. As for the slave cylinder, the one
on my jeep was INSIDE the transmission housing near the clutch assembly,
which meant disconnecting the transmission from the engine to service the
slave cylinder. I am not sure how the OBW is set up. You might be able to
access it from outside the transmission housing.

Do have fluid dripping on the ground from under the transmission?

 

[Gerard]

Don't know if your model has the hill holder but I had exactly the same
symptoms and it was a maladjusted hill holder at fault. I have a 2000 OBLW
and after a proper adjustment and grease (and a full flush of clutch fluid
just in case) it has not caused me any trouble in 6 months.

I thought I was going to need a whole new clutch - was quite happy to find
it was a cheap and easy solution.

Every time the car got hot, the pedal would eventually end up stuck on the
floor and I'd have to pull over, let the car cool down and then get going
again.

Hope this helps

Gerard...

 

[Mike]

Don't know if your model has the hill holder but I had exactly the same
symptoms and it was a maladjusted hill holder at fault. I have a 2000 OBLW
and after a proper adjustment and grease (and a full flush of clutch fluid
just in case) it has not caused me any trouble in 6 months.

I thought I was going to need a whole new clutch - was quite happy to find
it was a cheap and easy solution.

Every time the car got hot, the pedal would eventually end up stuck on the
floor and I'd have to pull over, let the car cool down and then get going
again.

Hope this helps

Gerard...

What a coincident - I was going to post the same question today about
my MT clutch and high temps. I live in a hot climate and noticed when
the temp climes above 105F, the clutch engages/disengages very low to
the floor and the pedal also does not return to the top. The problem
goes away again in the AM when temp drop, but then returns in the
afternoon when temps climb again. This is the first hot summer I have
had this problem, and it just had it's 32K service performed. The
dealer where I have it serviced is somewhat out of the way, so is
there an adjustment or fluid that can I can check first?

Thanks for any advice ('01 Forester, 33K miles)

 

[camss]

I have the same problem on my '99 OBW. I believe I have found the Subaru
technical service bulletin which addresses this problem on several manual
Subaru models. It's TSB 03-52-03 and it involves replacing the clutch
hose and clutch operating cylinder.

You can print a copy from here:
http://www.scoobymods.com/forums/showthread.php?s=&threadid=2041