Intermittent slipping clutch on 93 legacy turbo

[kip]

I have owned this car since new. It is a terrific car.

However, within the first 1000 miles from new (1993!), I started having a strange clutch slipping problem. It seemed to be related high ambient temperature. The clutch pedal (hydraulic system) would get firmer and the "slack" would be disappear. Eventually, the clutch would become disengaged enough to slip at peak power output due to this apparent increase in hydraulic pressure.

My dealer (idiots) simply replaced the clutch at 5000 miles after months of my pain. The new clutch slipped the next day on my way home from the shop.

I ended up adjusting the threaded adjusters under the dash to give some more "slack". This worked fine and I was happy...

Well, now it is 10 years later and the problem has returned. It only happens on 20 mile+ drives and on hot days. When I commute south (San Francisco to Palo Alto) to work, the clutch pedal will get very firm and the clutch will begin slipping by the time I get to work. In the reverse commute I usually don't have the problem because it is cooler in SF. The car only has 97K miles and has been meticulously maintained. I do not think the clutch is bad as it doesn't slip at all unless the pedal gets firm.

So... Whats the issue? Bad master? Slave? I am going to change the fluid this weekend. I could adjust the adjusters again, but when the car is cold and it is cool out, the adjustment is perfect. I was under the impression that the hydraulic system is self adjusting.

Oh... and I do have the clutch shudder problem that people seem to discuss a bit.

BTW, I have been looking for a site like this for about 3 years!!! Nobody knows anything about this car! Great to find you all.

-Kip

[eastbaysubaru]

I can't provide much assistance on this topic, but was just curious if you're planning on coming to the Subaru meet this Sunday in San Jose. A few of us BC BF guys will be caravanning to the meet and parking together to represent the first gen. Legacy's. PM me if you're interested.

-Brian

[kip]

More info on this issue here
http://bbs.legacycentral.org/viewtopic.php?t=15237

[entirelyturbo]

Welcome Kip, glad to see someone who has been in love with the car since new! Very few of us here are the original owners of our cars

Depending on how hard you are on the clutch, it may be time for a new one. If the adjustment you made has lasted for 10 years, then I could imagine that the disc is worn down. But 97k miles is an early demise for a clutch, especially a Subaru one.

I don't know much about the hydraulic clutches (my nonturbo is cable), but when was the last time you flushed the system out? You say it's temperature-related, I'm thinking that maybe the thermal expansion of the fluid is causing the slave to partially disengage the clutch. Maybe the fluid has moisture in it...

[kip]

Welcome Kip, glad to see someone who has been in love with the car since new! Very few of us here are the original owners of our cars

Depending on how hard you are on the clutch, it may be time for a new one. If the adjustment you made has lasted for 10 years, then I could imagine that the disc is worn down. But 97k miles is an early demise for a clutch, especially a Subaru one.

I don't know much about the hydraulic clutches (my nonturbo is cable), but when was the last time you flushed the system out? You say it's temperature-related, I'm thinking that maybe the thermal expansion of the fluid is causing the slave to partially disengage the clutch. Maybe the fluid has moisture in it...

Yep. I was pretty fired up to be able to afford such a cool car fresh out of school. But believe it or not, the turbo's weren't selling and I got it for a great price. My only regret was the lack of a 5sp in the wagon. Would have definitely bought one if it existed.

I got 180,000 miles out of my volvo clutch driving it like a rally car. I am hard on the subaru, but most of the clutch wear has come from this slipping problem. If the radio is loud, I don't notice the slipping while on boost. The clutch works perfectly fine when its cold out and the pedal hasn't gotten too firm. It does have a bit of subaru shudder, but its been like that forever.

I plan on doing a clutch with the next timing belt replacement (120,000)

I changed the fluid and bled the system a few months ago. No change. I am 90% sure the problem is a faulty master cylinder. I have a rebuild kit but I haven't put it in yet.