Clutch Issue or Master???

Okay, z28, 80,000 miles. Everything's stock. Yesterday morning it was a little colder than normal here (upper 40s in the am), rolled out of the driveway and went to go into first, and clutch pedal was stuck on the floor. After pumping it some, I was able to get it in gear, although the pedal felt soft and engaged very close to the floor. After going through the gears a couple times, pedal feel got better.

Later in day when temp got to 70 here, drove home. Pedal was back to normal. Later that night, temp back in the low 50s, clutch got soft again. I'm leaving here (50* right now) in just a bit, so I'll report if it's the same.

Anyway, I've been reading a lot and sounds like the hydraulic system is crap in these cars. Anyone have any recommendations as to what my problem could be?

when was the last time you flushed teh fluid?

Quote:

---

Originally Posted by MYSCZ06

when was the last time you flushed teh fluid?

---

I bought the car about a month ago, so I have no idea. I haven't done it. I'll check the fluid tomorrow morning. Been busy as shit lately.

Start by changing the fluid. I use ATE Super Blue DOT 4 fluid, but a good brand name DOT4 fluid will work also. Valvoline makes a Synthetic DOT3/DOT4 fluid you can get at most auto parts stores. The Super Blue is also nice because you know when the system is completely flushed since the fluid comes out blue instead of brown.

If you flush the system and its still acting up, then you probably have a master or slave cylinder on its way out.

Quote:

---

Originally Posted by Wesman

Start by changing the fluid. I use ATE Super Blue DOT 4 fluid, but a good brand name DOT4 fluid will work also. Valvoline makes a Synthetic DOT3/DOT4 fluid you can get at most auto parts stores. The Super Blue is also nice because you know when the system is completely flushed since the fluid comes out blue instead of brown.

If you flush the system and its still acting up, then you probably have a master or slave cylinder on its way out.

---

I thought I was reading on here to use dot 3, and to stay away from dot 4 because it could break down the seals/gaskets. I thought they were the same thing, with the 4 having a higher boiling temp. Someone please confirm. Thanks for everyone's help so far.

Oh, here's a separate issue, although not really a problem. I am able to start the car without engaging the clutch. I'm assuming the previous owner bypassed it for a car starter or something like that. Anyway, I don't think that this has any bearing on the issue at hand, but thought I'd share just in case.

Quote:

---

Originally Posted by tpilews

I thought I was reading on here to use dot 3, and to stay away from dot 4 because it could break down the seals/gaskets. I thought they were the same thing, with the 4 having a higher boiling temp. Someone please confirm. Thanks for everyone's help so far.

---

You read some incorrect information. DOT5 (silicone) brake fluid is the type that is incompatible with conventional brake fluid. Using DOT5 in the brake or clutch systems of these cars will ruin the system.

DOT4 is merely a higher temp version of DOT3. They are interchangeable with each other, and neither will cause any damage to your clutch or brake system. DOT4 is better than DOT3, so try and use that if you can.

Just an update....

Opened the reservoir and the fluid is pretty much black. It was a little low, so I topped it off because I was stranded at work and it was 44* two nights ago. After topping it, the clutch built pressure and I was able to get home. I'm going to flush the entire system this week when I actually get a few minutes. I figured it was the fluid, but wanted to get some other opinions before I moved forward.

Thanks for everyone's help.

I just wanted to say I just went through the same problem. I checked the fluid down a little then checked to see if the master was leaking it wasn't. So I jacked it up looked to see if the slave was leaking. I noticed that the back off the oil pan was wet but not oil ended up being break fluid and the problem turned out to be the clutch slave.

Well, just a semi-update. I've got a leak somewhere in the system. Every 4 or 5 days, the master reservoir is down a bit and the clutch sticks. Soon as I top it off, everything's great. I haven't been able to locate the leak; really hoping it's the master cylinder. I finally have some time tomorrow to get under the car and check things out. Will update later.

Quote:

---

Originally Posted by tpilews

Well, just a semi-update. I've got a leak somewhere in the system. Every 4 or 5 days, the master reservoir is down a bit and the clutch sticks. Soon as I top it off, everything's great. I haven't been able to locate the leak; really hoping it's the master cylinder. I finally have some time tomorrow to get under the car and check things out. Will update later.

---

Hate to be the bearer of bad news but its probably the slave. Much more common to have to replace the slave than the master cylinder. Check the weep hole between the bellhousing and oil pan, if its wet or dripping, its the slave cylinder. Its tough to see the master because its buried below the power booster, but you can check for a leak by looking under the dash where the pushrod goes into the cylinder, behind the clutch pedal.

I had a similar issue- when I dropped the trans the throwout bearing and spring fell out (along with the part of the slave that the throwout is attached to.) Needless to say, I'm going to assume the slave cyl being in three parts may have been the cause of my erratic clutch pedal behavior.