Weird Clutch Failure

Status
Not open for further replies.
Joined
Dec 13, 2018
Messages
55
Location
ON
Car is a 2004 Toyota Celica GT, 266 000 km. About ~60 000 on current clutch according to previous owner (no receipt, but I trust him when he said it was done since the clutch is quite grippy and has operated perfectly thus far).

Yesterday I made the hour drive to the college for class, then I was the only one who showed up so the teacher called it after 10 minutes. Went back out to the lot to leave, got in my car, and found that with the clutch depressed I can't shift into any gear. Went from perfectly operational to zero operation in the span of ten minutes.

Transmission still shifts smoothly with the car off. Pedal feels normal. A passerby was nice enough to confirm that when I press the pedal, the slave cylinder does press on the clutch fork. Unable to fix anything in the parking lot of the college, I started the car while in second gear and drove home that way (no fun at all doing 55 km/h at 4000 rpm for an hour and a half on back-roads). At multiple times during the trip I tried to see if the clutch came back, by taking my foot off the gas (engine braking) and depressing the clutch pedal to see if I began to coast; Nothing. Clutch always engaged.

Anyways, now that I'm home my father confirmed again that the clutch slave cylinder IS moving, but the clutch doesn't disengage since it still won't go into gear. No leaking, no weird noises, nothing unusual except that the clutch is always engaged. That is my only symptom

Possibilities I can think of:

- Some sort of hydraulic failure that causes the clutch slave to stop before it reaches it's full travel (unlikely, but the cylinder costs $12 and can be reached from the top of the engine bay so I am replacing it anyways). Master cylinder is more involved, but also pretty cheap.

- Clutch fork or pivot ball failure, causing the action of the slave cylinder to not press the release bearing as intended.

- Friction plate welded to flywheel (unlikely, as I felt a slip a few times on my drive home when starting in second gear)

I ordered the entire clutch kit, master cylinder, slave cylinder, etc. since I got a good price and I like keeping spare parts on the shelf. Only things I haven't ordered are clutch fork and pivot ball, since I need to go to the dealer for that.

Plan is to replace the slave cylinder, bleed it, and test. Then the master, bleed it, and test. After that, it's time to pull the transmission and inspect the mechanism.

Thoughts / suggestions?
 
Order a new rear main seal, too. Easy to do once you drop the transmission, and it's right by the clutch. If that seal leaks, you get oil all over your clutch and will have to do the job again
cry.gif
 
FYI you can shift without the clutch. Just rev match your gears. No noise no damage. Only time I use the clutch is to get moving. I'm going to assume that your hydraulics have failed and are not moving the fork enough to release the clutch. That's where I would start before tearing the trans out.
 
Last edited:
The two major causes are lack of clutch fluid or a bad master cylinder (or if the system has just been worked on, air in the line). The slave cylinder doesn't do this except by leaking to cause a lack of clutch fluid.
 
Thanks for the input everyone
smile.gif


Just to clarify, I ordered all the parts but I never intended on removing the transmission unless both slave and master cylinder replacement failed to fix the problem. If the clutch kit isn't needed, I'll just keep it with my other spare parts.

A few minutes ago I decided to bleed the slave cylinder (to see if air came out) with a one-man bleeder kit I have. After two pumps, nothing more would come out (fluid or air) and the reservoir level remained unchanged. I suppose this means that the master cylinder is likely to have failed, as mentioned by Chris142 and mk378. Presumably it isn't pumping properly to the slave cylinder, and isn't drawing any fluid from the reservoir. When the parts arrive, I'll do master and slave cylinders first as planned and see what happens.

Thanks again
smile.gif
 
I had that happen years ago on an Isuzu. Pressure plate failed, that is what a mechanic said. That was a cable operated clutch, and the clutch felt lighter than normal. Anyhow. Spring snapped and with the pedal to the floor it would only halfway disengage—if I was in gear, moving, I could step on the clutch and make it slip.

As I wasn't home I wound up starting it in second gear, then shifting to 4th or 5th. Not sure why I did that, maybe I wasn't aware of rev matching or something—I was like 16 at the time.

I replaced the disc too even though it looked fine. New pressure plate and all was fine.

In your case, perhaps the hydraulics went out, hard to say, not sure if you have to drop the trans anyhow to get to the slave cylinder.
 
Originally Posted by supton
I had that happen years ago on an Isuzu. Pressure plate failed, that is what a mechanic said.


I was thinking that's a possibility, but hopefully it is just the hydraulics.

Originally Posted by supton
In your case, perhaps the hydraulics went out, hard to say, not sure if you have to drop the trans anyhow to get to the slave cylinder.


Conveniently the slave cylinder is right on top, I can reach in and remove it without getting under the car or removing anything else.

The master cylinder, unfortunately, is buried in a crevice between the shock tower and the firewall directly below the wiper area. I'll probably need to remove the brake master cylinder too, as it obstructs the way in there.

I hate working on FWD cars for this reason. Everything is so cramped.
 
Many years ago I had the same symptoms on a Chevy Luv. I bought the slave or the master to try it out and the parts guy said you should buy both. He was right. I was back for the other and all was well after replacing both. I doubt you have an internal transmission issue. Hydraulics get tired with age. Please post the outcome.
 
Originally Posted by WondrousBread
Originally Posted by supton
I had that happen years ago on an Isuzu. Pressure plate failed, that is what a mechanic said.


I was thinking that's a possibility, but hopefully it is just the hydraulics.

Originally Posted by supton
In your case, perhaps the hydraulics went out, hard to say, not sure if you have to drop the trans anyhow to get to the slave cylinder.


Conveniently the slave cylinder is right on top, I can reach in and remove it without getting under the car or removing anything else.

The master cylinder, unfortunately, is buried in a crevice between the shock tower and the firewall directly below the wiper area. I'll probably need to remove the brake master cylinder too, as it obstructs the way in there.

I hate working on FWD cars for this reason. Everything is so cramped.



Did you get it fixed? Curious as to what caused the issue.
 
Originally Posted by MarkM66
Did you get it fixed? Curious as to what caused the issue.


So for a quick update, no it is not yet fixed.

I replaced the clutch slave ($12), bled it, no difference. Then replaced the clutch master (~$29, which did in fact require removing the brake master for access), bled, no difference. Clutch pedal still feels completely normal. Clutch fork still moves.

As an aside, the slave cylinder was old and crusty and clearly near the end of it's life (made a scraping noise), but functional. The master, contrarily, looked and functioned like new. The possible issues now come down to clutch fork / pivot ball, pressure plate, or something jammed that is preventing disengagement.

As I type this the car is cooling down, and I will have to begin tonight / tomorrow with the transmission removal. I have a clutch kit prepared, which will be going in regardless of the issue since pulling the transmission is irritating enough that I'd rather not do it for a long time. If I need a clutch fork / pivot ball, I'll have to order them from Toyota since I haven't found any aftermarket offerings. But that will be dependent on what I find when the transmission is removed.

It might be a few days before I update again, since I've never pulled a transmission on a FWD car. Hopefully it isn't as bad as it is made out to be on the Celica forums I've viewed.

Thanks again everyone
smile.gif
 
this sounds exactly how it went when my pressure plate failed on my newish valeo clutch in my old Pontiac Sunbird, full movement of the pivot arm off the slave but no disengagement.
 
Excited to see what you find! I keep waiting for my darts slave cylinder to go out. It's relatively common and the first dart I had did so at 22,000 miles. It is also internal. Ugh why ? Make it easy to change......engineers!
 
So after fighting to get the transmission out, this is what I found.

JSZNJgC


Seems like something weird happened with the springs in the friction disc. They rattle around if I shake it, and one of them has a shard of metal missing. Presumably this piece found its way into a crevice between the friction disc and the pressure plate and jammed them in the engaged position, regardless of the hydraulics trying to move them. The whole hub is slightly loose, and not connected very sturdily to the friction material.

Curiously, the friction disc is an Exedy replacement. The friction material is pretty solid, it was purely a failure of the sprung-hub of the disc. The throwout bearing also makes a slight noise, but not something that would've caused any sort of problem for a very long time.

Either way, a full replacement clutch kit is going in.

FRbSoQi


Flywheel is looking very good. I'm pretty sure the marks on it are from resurfacing, meaning this clutch didn't even wear down the resurfacing marks. I know people say to get it resurfaced or replaced every time, but unless I find something later when inspecting it more thoroughly I'm probably just going to use it as-is.

EDIT: Well, for some reason the images are broken. They are there, you'll just have to click the Imgur link if you want to see them. My apologies.
 
Last edited:
Status
Not open for further replies.
Back
Top