Subaru clutch question: Grassroots Motorsports forum: Grassroots Motorsports Magazine

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April 6, 2010 4:24 p.m. David S. Wallens Editorial Director

You guys are smart and seem to appreciate a good riddle. This tech problem comes from a friend and concerns her 1999 Subaru Outback wagon:

When I start driving, the clutch is perfectly normal. If I'm on a long highway trip, it stays fine. If I'm in city traffic using the clutch a lot, the clutch pedal starts to stay on the floor instead of popping back up. Yesterday, after 2 hours in traffic, clutching constantly, it started to not want to engage until it was way at the floor.

Then 3 hours later, when the game was over, the clutch acted normally again. I've only ever owned manual shift cars, and I've had clutches go bad before, but I've never had a clutch do this. Weird.

So, any advice? Her mechanic was equally stumped.
April 6, 2010 4:31 p.m. 93celicaGT2 SuperDork

I find it a little odd that the mechanic would be stumped, too. This sounds like slave cylinder to me. Or horribly hilariously bad and old fluid?
April 6, 2010 4:54 p.m. Kramer HalfDork

David, call the guys at Exedy. They make the OE clutch for this-they'll be able to answer your question. I'd help, but I no longer work there.
April 6, 2010 5:26 p.m. Johnboyjjb New Reader

My 2000 Impreza had a TSB for a clutch that did that. The TSB said it was the slave cylinder but the dealer said it was an improperly torqued pressure plate. When they retorqued the pressure plate they rebled the clutch and it worked fine.
April 6, 2010 5:32 p.m. Nashco SuperDork

This is a word problem, so proper wording is important.

Engage = disengage??? When you push the clutch pedal in, you disengage the clutch. A clutch pedal slowly needing to get pushed further to the floor to disengage the clutch sounds like a hydraulic issue, I'd suspect slave related if it gets worse with heat.

When the game was over = clutch wouldn't engage at all??? Did they pull to the side of the road and let it cool off? I don't know what "game was over" means.

More useful information: Impreza or Legacy? Or, more importantly, which engine (2.5 Legacy or 2.2 Impreza)? This will dictate if it's cable (pull style) or hydraulic (push style), IIRC. Have they had any work done with the clutch before? What and when, if so? If not, how many miles are on the car? When the pedal has to get pushed further to the floor to disengage, what happens if you pump the clutch fast a few times...any change in pedal height where it disengages?

I'm guessing it's a Legacy, which means hydraulic clutch pedal. It's possible, but highly unlikely, that there's blockage in the line making the pedal work inconsistently. More likely is that the slave cylinder is on its way out.

Bryce
April 6, 2010 5:33 p.m. iceracer HalfDork

Master cyl or slave cylinder. May need just fresh fluid and a bleed.
April 6, 2010 5:57 p.m. David S. Wallens Editorial Director

Nashco wrote:

I don't know what "game was over" means.

She drove it to a baseball game. I'll get more info on Impreza vs. Legacy.
April 6, 2010 6:12 p.m. DILYSI Dave SuperDork

It's one of the cylinders. Assuming it's been doing this a while, then that leads me to think it's an internal leak or she'd have lost all the fluid by now.
April 6, 2010 6:20 p.m. Nashco SuperDork

David S. Wallens wrote:

Nashco wrote:

I don't know what "game was over" means.

She drove it to a baseball game. I'll get more info on Impreza vs. Legacy.

Ha...I didn't even consider the LITERAL meaning. Doh!
April 6, 2010 6:22 p.m. David S. Wallens Editorial Director

Nashco wrote:

David S. Wallens wrote:

Nashco wrote:

I don't know what "game was over" means.

She drove it to a baseball game. I'll get more info on Impreza vs. Legacy.

Ha...I didn't even consider the LITERAL meaning. Doh!

Yeah, baseball. You know, take me out to the ball game and all that stuff. I think it was opening day, too, when this all went down. Thanks for the help, too.
April 6, 2010 7:11 p.m. carzan Reader

Our '93 Miata exhibited similar behavior. It was the slave cylinder.
April 6, 2010 8:26 p.m. Streetwiseguy Reader
David S. Wallens wrote:
1. If I'm in city traffic using the clutch a lot, the clutch pedal starts to stay on the floor instead of popping back up. .
This sentence sticks out at me. I would suggest making sure the Master cylinder pushrod is not adjusted too long. It sounds like the reservoir port is not being uncovered, either because of a misadjusted pushrod, or the piston is getting hot and growing, and not returning all the way. My first inspection would be of the master cylinder, anyway. If the slave were sticking, the pedal would probably return ok, but the clutch should slip rather badly the more you pump the pedal.