Clutch not working!

[vincent52100]

Well I got the fuel pump etc in my 87 MR2. Got it started and the clutch wouldn't release. As the previous owner had problems with clutch release I replaced both the master and slave cylinder with new units. Bled the clutch with a vacumn bleeder., Still no clutch. To make a long, frustrating story short, I have bled it with a vacumn bleeder, with someone pumping the clutch and by leaving the bleeder open and letting gravity do the work with both the clutch pedal up and depressed over long periods of time. I can see the slave cylinder moving the fork. I even made an extension for the rod on the slave cylinder to make up a little of the free play. Have pumped 2 qts of brake fluid through it through all of this. Still will not release. Can I assume the problem lies with the clutch/pressure plate? Thanks for any advice.

[palos]

There is a current thread with a somewhat similar scenario started by fvillota. In his case, the flywheel bolts sheared off. When engaging the starter, have someone look to see whether the crank is turning either by looking at the crank pulley or by removing the spark plugs and looking at the pistons.

Was there any evidence that the slave cylinder may have leaked and contaminated the pressure plate?

It may be helpful to list (summarize) all the maintenance items replaced since you last had the car running and other procedures performed.

[328FTW]

Has it been sitting? The clutch can stick itself to the flywheel over time. My normal solution for it was a push start in second gear then thrash the sh** out of it to try and make it crack free. Even if the clutch is still stuck you did get to thrash the car a little.

[vincent52100]

Hi. The engine runs fine. I driven it 4 times by starting it with the tranny in 1st. The car will tend to creep even with the clutch depressed all the way. I've had to speed shift it even with the cluch all the way down to change gears. No indication of leakage around the old slave cylinder before I replaced it. The new one is clean as a pin, no sign of any leakage. It does run like a striped-a**-ape!

[328FTW]

Sounds like it isn't fully disengaging. I had a mkI do this and it turned out the throwout fork had broken away from the throwout bearing somehow and was kinda only halfass pushing the pressure plate diaphram. How does the pedal feel, much play?

[tjmr2]

I think you may find some additional adjustment at the top of the clutch pedal where it attaches to the master cylinder that might help you achieve longer throw.

Good luck

[palos]

I'm not an advocate of the "buy OEM parts only" line of thought, but you may want to check whether you bought the correct parts or that the correct parts were sold to you.

You stated that you added an extension to the slave cylinder rod. I only have the BGB for a MK1, but there isn't any adjustment procedure for the slave (release) cylinder. Perhaps, you didn't receive the correct part. See if the part number on the slave matches the part number on the box and confirm with your parts supplier.

And as tjmr2 suggested, perhaps the master cylinder's push rod isn't correctly adjusted.

[Jackstand Queen]

Your experience with the titanic effort of bleeding the master and slave cylinders is par for the course.

This is a very, very, very trying experience. My guess is you still have a bubble in the hydraulics. Is the clutch the slightest bit spongy? It should be firm, and movement should be consistent, smooth, gradually increasing in resistance.

I've had the best luck with using a pedal pumper assistant. And then opening and closing the valve with each pedal cycle. And its still the Mother of all Bleeding jobs!

If your pedal is good and firm, you probably have some clutch/throw out bearing issue going on and will have to Drop Tranny. I've had what 328FTW described happen to me a few times. The fork that pushes against the throw out bearing gets slightly out of place, and the clutch doesn't work worth a damn. I've shimmed up the bolt that acts as a pivot point for the fork . . . in order to fix it.

[vincent52100]

Thanks for all the info. The pedal feels like there is not much resistance all the way to the floor but I can see the slave cylinder moving the fork. I've tried all different positions on the rod adjustment on the master cylinder. I did do a side by side comparison on the old parts and the new and they were identical. And here is what I'm afraid is the killer. I manually (with a bar and ratchet strap) pulled the fork all the way, just as the slave cylinder would push it, and still have the same problem. Am I in big trouble? Thanks much.

[lsgheero]

I would like to note that I was having issues with my clutch (still waiting on my shifter bushings...) however I found that the peice on my car that you adjust for short longer throw (the peice that screws onto the pushrod) was bent. I will post pics when I can. I found another at the scrap yard off a ae86 and works great again altho I still have issues getting in gears sometimes but its no longer the clutch at this point... hoping new bushing will resolve this


Hope that helps.. altho I imagine my case is very rare.

[muffinman]

I think the best thing to do is pull the trans and replace the clutch , besides compared to the fuel pump dropping the tranny is a breeze.

[Jackstand Queen]

Vincent:

The soft clutch feel doesn't sound right. Do you work out? Are your legs unusually strong? Because after a minute or two of holding the clutch down, your leg should start to feel fatigue.

Another symptom of the clutch fork getting out of sync with its function is that it becomes floppy. Subject to sideways and/or up and down movement. If the fork is not firmly in place, you're gonna have to drop Tranny. Shimming up the pivot bolt about 1/8" more, or less . . .. . should fix it.