Clutch Failure and Grinding Noise

Hello all, it's been a long time since I've been on. I was on here a couple of years back as "oz_hole" with a 92' green 4 door up in Rhode Island.
Now I've got a stock 97' 2wd, manual, 170k miles.

So I was driving through the lot at work today in 2nd gear and went to shift. I felt the clutch resist and then feel like I was jamming/breaking something to try to engage it.
I stopped and pushed the clutch in and I got a grinding noise. I looked at my slave cylinder and there was fluid, but it also looked like it kinda blew apart on the shaft inside the cab. The plastic piece that tapers down from the firewall was broken right there and freely sliding along the shaft, it almost looked like threads with a spongey o-ring? And the ball joint connector to the clutch pedal was blown out.
So I'm thinking that it shouldn't be too bad, just needs a new slave and i try to start it. I've got to really jam in the clutch and then the engine turns over really slowly, like there's a battery issue. But it finally catches and the grinding noise begins until I let out the clutch. And slowly engaging the clutch I can almost "feel" a spinning motion being transferred through the pedal just as the grinding begins.

I've done the search and haven't seen an issue described like this, so any help would be greatly appreciated.

oscar.zulu said:

I looked at my slave cylinder and there was fluid, but it also looked like it kinda blew apart on the shaft inside the cab. The plastic piece that tapers down from the firewall was broken right there and freely sliding along the shaft, it almost looked like threads with a spongey o-ring? And the ball joint connector to the clutch pedal was blown out.

Click to expand...

welcome back, unless im missing something, thats the master cly... the slave is inside, or nestled up next to the trans depending on year.

if its the master cyl, thats an easy 30 minute job, hardest part is the under dash work. having a 2nd person to help bleed the clutch helps if your low-tech like me.

You buy the slave and master as a single unit, don't open it, just uncoil the thing and bolt it in on both ends. No bleeding involved unless you open it before you put it in.

my jeepforum write up on it.
the pre-bled clutch/master is just over a hundred shipped from rockauto.

Tools:

• 1/2" deep well socket
• extensions
• needle nose pliers or small screwdriver

Removal:

1. Remove (2) 1/2" nuts/studs from slave cylinder to clutch housing
2. Remove slave cylinder from clutch housing
3. Disengage clutch fluid line from body clips
4. Verify clutch master cylinder cap is on tight
5. Remove (2) 1/2" clutch master cylinder attaching nuts, one from inside above clutch pedal, other from engine bay below master cylinder
6. Remove cotter pin holding clutch pedal to master cylinder push rod
7. If pedal pin is equipped with bushing, inspect, replace if worn
8. Remove clutch hydraulic linkage through engine compartment
   (I positioned a drain pan below, cut the line, drained the fluid into it by opening the MC cap, and slid it right out)
9. Disconnect clutch pedal position wires
   (mine did not have these)

Assembly:

1. Be sure master cylinder cap is on tight
2. Position clutch linkage components in vehicle
3. Work slave cylinder downward through engine bay so that hydraulic line is tight to body, parallel to brake & gas lines
   (Ok, the line on mine did not want to fit between the brake booster and the seam at the dash panel/cowl. I had to get a little ugly on it with pliers so that the line would go down behind there. When you take yours out, see if it fits through there, and do what you need to before putting the new one in.)
4. Position master cylinder in dash panel
5. Attach master cylinder push rod to pin on clutch pedal
6. Install and tighten clutch master cylinder attaching nuts, tighten to 200-300 INCH pounds.
7. Insert slave cylinder push rod through clutch housing opening and into release lever. Be sure cap on end of rod is securely engaging in lever. Check this before installing cylinder attaching nuts.
   (Don't take the white plastic piece off the slave, it's designed to break off inside the first time you use the clutch.)
8. Install and tighten slave cylinder attaching nuts/studs, tighten to 200-300 INCH pounds.
9. Secure fluid lines in body clips
10. Connect clutch pedal position wires
    (mine did not have these)

Exploded Views:

One piece, non serviceable, clutch & slave cylinder assembly:
Don't take the white plastic piece off the slave, it's designed to break off inside the first time you use the clutch.

Other pics:

Click to expand...

Thanks guys, yeah looks like I got my parts mixed up, it is the master that has failed inside the cab.
Last time I did a master cylinder change was on my 92' on the side of I-95 and I didn't realize that the slave it wasn't internal on this one until now.

So if anyone can tell me what it is exactly that is grinding? I've had a few guesses here at work that it's the throwout bearing, and I'm really hoping for the cheaper answer.

Thanks again,
Ozzie

The report of resistance, then grinding, does not sound good. When you say you hear grinding, is it grinding simply when you depress the clutch? If so, it's possible you have a throwout bearing failure, or what happened to mine, which is that the throwout bearing failed, ate the fingers off the diaphragm, jammed, and the grinding noise was the clutch lever being chopped to bits by the pressure plate!

A hydraulic failure of some sort is almost guaranteed when the mechanism goes bad. But you may not get a really good idea of this until you replace the failed hydraulics, since you can't look very well inside, but you should probably pull the slave first, and see if you can see physical damage to it.

Thanks xcm, Rich, Matthew and Duece, especially for that write-up.
We'll get the clutch cylinders replaced with the kit tomorrow and hopefully that'll do it.

Thanks again, my wife was well impressed by the support shown by you all.
Of course I said that I wouldn't have been able to do what I did to my old Jeep without



Yes, I live in the past... especially with my red stocker.

Re: Things That I've Found in My Clutch Housing

ok, so I started the clutch master/slave cylinder kit install, but when I removed the old S.C. this is what I found:








I stuck my finger in the hole and managed to push the rest of the SC deeper into the clutch housing... yeah!
I went and got a magnet and fished around inside and pulled out these pieces:



my questions so far are
1) Is the bent wire from the SC?
2)should I be worried about anything else laying around inside the clutch housing?
3)Is the failure of the SC push rod what was causing the grinding?

And finally here is a shot of the fork (which appears to be resting pretty close to>>) and a surface that looks like it has some wear (again, my apologies for lack of tech)

And up to this point my clutch has been perfectly fine...

How does this look?



Thanks again for all the help.
Ozzie

That looks discouragingly like mine after the throwout bearing failed. I think what you're seeing in there is that the fork has been rubbing against the outer edge of the pressure plate, hence the grinding noise. If you look at the spot on the fork just inboard of the spot where the slave cylinder rod pushes, you'll see a scorched spot. That's where the pressure plate has nearly worn it through. The left of the two pieces of spring is part of the spring that is supposed to retain the opposite end of the fork on the pivot ball. It has probably popped off at the other end. The fork should not be down that close to the pressure plate at the slave end, and though it's possible that this was caused by the pivot end unseating, it's more likely that the throwout bearing is either gone to pieces or passed through the diaphragm. Either way, though, you're going to need to open it up, and likely to need a new clutch.

Exactly. It was the retaining clips on the throwout bearing that had failed and caused the fork the additional travel to allow grinding against the pressure plate as I pushed in the clutch pedal.

The bearing didn't actually cause any damage other than the subsequent grinding of the fork.

Now I've got a new clutch and compared to the old leg-press-clutch this one throws like butter.

Thanks again for all the help,
Ozzie