I installed a McLeod RST clutch, Tick adjustable master cylinder, and slave cylinder earlier this year. Still using the stock flywheel. I measured to determine if I need a shim and installed one so that the throwout bearing with the spring removed is about 5mm (0.19in) from the clutch fingers. I've since had two slave cylinders fail.

The first time the slave cylinder failed, I thought it was due to having the master cylinder adjusted incorrectly with too long of a throw, causing too much pressure on the slave. The second time I installed a slave cylinder, I adjusted the master cylinder all the way in and backed it out gradually until the clutch engaged smoothly. The clutch pedal is about 1 inch lower than my brake pedal. The clutch felt great with normal driving and I had no problems shifting. I just finished my 500 mile break-in on my rebuilt engine and finally revved above 4k rpm and as soon as I did, I lost clutch fluid pressure and was unable to shift. The clutch line was still intact and looked fine, so something inside the slave cylinder broke and released the fluid.


One important note is that occasionally I have a fairly strong vibration coming from the clutch/slave area. It only happens when in gear and accelerating above 2-3k rpm. As soon as I press the clutch, the vibration goes away. I don't believe the vibration is due to the clutch being imbalanced. I had it balanced with the flywheel prior to installing. Keep in mind this is an intermittent vibration. Sometimes I can accelerate and feel nothing at all, but other times I get the vibration. The first time I felt this vibration, I used a scope to look into the bellhousing at the slave cylinder. Both slave cylinder bolts were still tightened down and I didn't notice anything out of the ordinary.

Both times the slave cylinder has failed, the bolts have backed out completely. The second time I installed a new slave, I re-tapped the holes and used red loctite but the bolts still backed out. I'm not sure if it's due to the vibration or excessive pressure on the bolts.


I went ahead and ordered new couplers and bearings for the torque tube just in case that's what's causing the vibration.

I'm hoping someone can provide insight as to why this is happening. This is the second slave cylinder I've had go bad within 500 miles. I've removed the bad slave cylinder and torque tube and am waiting on the new parts to come in. I'd like for this to be the last time I have to install a slave cylinder.

 

Why is the inside of the slave damaged? Shaft runout?

 

Couple things. Just because you had it balanced doesn't mean they did it right, Seen many times not balanced properly.
Second did you check harmonic dampener to see if its wobbling.
Third ,get rid of that stupid tick MC. Your just throwing in a variable. The stock MC is perfect no screwing around. I had a tick myself started to have shifting went back to stock and i have a twin mantic over 1k hp. I kicked myself in the *** putting in that stupid tick. My feel of the clutch is stock feel. Drove my buddies stock vett and couldn't till except for the little rattle. All this is just my opinion so relax and don't yell at me.

 

I'm not sure why the inside is damaged. It looks like the shaft pushed out too far but I have no idea why.

 

Thanks for the input demon. I'm fairly certain the clutch is balanced, mostly because I don't get the vibration every time and when I do, it goes away as soon as I push the clutch pedal.

Harmonic damper is fine. No wobble at all.

I'm happy with the Tick master cylinder. The clutch pedal feels great and can engage gears smoothly. I don't think that's the cause of the vibration. I'm still leaning towards the slave or the torque tube.

 

I have the TT out of my car now, here are pics:

I don't see any way to get the damage in your pics without there being something going on with your torque tube. Either out of balance or bearing issues. No noise from there when you were running it? I know just spinning it by hand on my bench you can judge the shaft runout and bearing condition.

 

For it to back out the bolts holding the slave something has to be acting on the inner surface of it, hence the damage.

 

Clutch, I learned a long time ago a assembly test procedure.

- Once a flywheel is installed and dialed in, I always Start the Engine.. No Vibration please.

- Once the Clutch Disk and Pressure Plate are installed,, Start the Engine. Yes, I have had several install that had a vibration at this juncture, always the Pressure plate. With the engine running I take a close look that the pressure plate Fingers, under a RPM range.

I'm wondering if the Pilot Bearing is Defective, because of the damage on the Release bearings Shaft on the inside. A damaged
pilot bearing can cause the shaft to move side to side when depressing the clutch.

C5 Pilot bearings can be a choir to install.

Did you install a new Pilot Bearing , and Did You or Did You not lubricate the bearing ???

Michael.

 

Frodo I think you're exactly right. I think the torque tube is the problem. I took it out of the car and spun it by hand and the shaft wobbles. I can't tell if it's the bearings or if it's actually bent. Once I get some larger snap ring pliers I'll remove the shaft and investigate further.

 

On the big snap ring: I had a pair of needlenose vise grips that I filed the tips down on, worked great.