Clutch bleeding

[metros]

Trying to bleed my clutch line. I'm having my wife pump the clutch pedal while I hold the slave cylinder fully open and open the bleeder valve. I'm getting a lot of air out but the pedal isn't getting stiffer. It still just goes to the floor and sits unless you pull it back up.

What am I doing wrong?

[philly15]

Are you saying she is pumping the clutch while you have the bleeder open? Also clutch takes forever normally if it's dry. I usually use a vacuum bleeder anytime a master goes dry whether for brakes or clutch, goes much quicker.

[metros]

Alright, update.

I read to remove the slave and point the nipple up to ensure air wasn't trapped in the slave cyl. I removed the slave, clamped it with a c-clamp to keep it fully compressed and used a vacuum bleeder while the slave was pointed up/line stretched upward. I got some air out of the system like this but then was just getting fluid. Put the slave back in place and unclamped it. Push the clutch pedal down and it sits on the floor again. When I have the slave clamped down the clutch pedal hardly moves. Maybe an inch.

This time I had the wife press the clutch pedal down while I applied vacuum and then closed the bleeder before she let off. Pump clutch pedal a few times, repeat. Still nothing.

SO frustrating! This is the only thing preventing me from firing the car up.

[metros]

One other thing that I've come across from reading. I can move my clutch fork all over the place easily. I can pull it all the way back to de-press the clutch slave cylinder. Am I going to need to drop the trans and check to see if the retaining clip is doing its job?

[Hindsight]

That doesn't sound right to me. It sounds like the clip is either off of the pivot ball or off of the fork. You have to push the fork hard onto the ball until the clip snaps onto it and holds it in place.

[metros]

Meaning I could still apply that pressure now to the clutch fork to try and seat it or I need to pull tranny to reseat it?

[STiPWRD]

It took me forever to bleed the clutch as well here are some tips:

Unbolt the slave (which you've already done), remove the slave push pin and boot and allow the slave piston to come out flush with the cylinder. Hold the slave cylinder up as high as you can and press the clutch in a few times. Make sure you remove the clutch pedal pin and push on the clevis by hand. This ensures max travel of the master cylinder back and forth. I used a screw driver in the master clevis for easier pumping. If you do it correctly you'll end up with some force built up in the slave cylinder, then reinstall the slave push pin, boot, and reinstall the slave cylinder back on the trans.

The clutch fork tip should be sticking up about half way in the middle of the opening in the trans, otherwise your throw-out bearing may not be seated inside the pressure plate. Maybe post a few pics?

[metros]

It sits straight up and down when I'm not manipulating it. But from what I've read I shouldn't be able to move the clutch fork by hand? Others have said it should take a lot of force to move it by hand and mine is easy to move forward/back.

I'm curious if I could get an angle to see into the opening for the clutch fork without tearing everything apart (AWIC set up).

Would the retaining ring not being seated affect the clutch pedal not building pressure?

[STiPWRD]

That's correct, when the throwout bearing is engaged to the pressure plate you will not be able to move it by hand. Try pulling back on the tip of the clutch fork really hard (towards the back of the car), this should seat it into the pressure plate ring and it should stay there. Sounds like you haven't engaged it yet. And yes, if the fork/throwout bearing aren't seated then the fork will be allowed to go all the way forward and exceed the range of the slave cylinder. Give me a call if you get stuck and need help. Here's a pic of mne as it sits now:
IMAG1327.jpg

[Quiny]

The clutch fork should be very stiff as others have said, it does need to be anchored to the pivot ball or pin, and engaged into the throw-out bearing. Without significant resistance on the slave cylinder rod the system will never bleed properly. I have always clamped the slave cylinder so the rod cant extend then bleed it with it clamped, if done correctly the pedal will get so hard it will hardly move. Once you have a good pedal remove the clamp. The pedal should return now provided the fork offers sufficient resistance.

[metros]

Thanks for the tips fellas. Hoping to get some time tomorrow to mess around with it some more.

Not having that engaged would explain why I'm doing all the right bleeding procedures without success. Is it normal to need to seat it like this after a clutch install? Or is it something I should have done while I had everything apart?

[Quiny]

It all gets seated in place when the tranny and engine gets put together. After the cases mate together the pivot pin needs to be installed for the fork then you jam it forward to engage the through out bearing to the pressure plate. You might be able to correct it without separating the case, remove the boot and and look inside. You should see the through out bearing flush with the pressure plate and it will not pull away.

[STiPWRD]

I usually pre-install the clutch fork, pivot pin and throwout bearing on the input shaft of the trans before I mate the trans to the engine. But you can also install the pivot pin after the trans is on the engine like Quincy mentioned.

[metros]

Positive update!
Removed the slave cylinder and pulled on the clutch fork. I could feel it interacting with something and gave it a good yank. It popped and now feels engaged. The tip of the clutch fork (outside the transmission) now moves about an inch by hand but otherwise doesn't have any play. Does that sound like an appropriate amount of movement?

I re-installed the slave cylinder and the clutch pedal has some pressure to it. It goes maybe halfway down and doesn't remain stuck on the floor. I think if I re-bleed everything I'll be in business.

Thanks to the help of the forum. The internet comes to the rescue yet again!

[STiPWRD]

An inch of travel on the clutch fork tip seems a bit excessive but hey if it works, it works. If I recall, my had about a quarter inch travel after the throwout bearing was engaged. You could try putting it in gear, pressing the clutch pedal and seeing if the rear wheels can be turned by hand. That will show if the clutch can be disengaged from the flywheel.

[brian b 36]

I think the master is not the same distance as stock that's why I un screwed the shaft to bring the pedal up and it is perfect know

[metros]

Next update:
I rebled the slave again last night with slave separate, piston fully compressed and helper working the pedal. Actually have less pressure on the clutch pedal now than before.

I'm not seeing any leaks and not getting much fluid out when I bleed it. Haven't come across any leaks.

Signs for bad master or slave? The slave piston isn't moving much when I'm pumping the clutch pedal.

[STiPWRD]

Another thing I tried that may help is unscrewing the fluid line coming out of the master cylinder and pumping it by hand (un-clevised) just to see if it was drawing fluid from the reservoir. Just gotta trouble shoot all the parts of the system one by one and isolate the problem.

[Bob_n_Cincy]

Metros,
One problem I've seen on here has been the adjustment of the clevis on the pedal. (end of MC rod)
The rod in the master cylinder must be all the way out before it will allow fluid to flow into the MC chamber from the reservoir.
The reservoir if remote, should be higher and the hose down hill to the MC. (not fun when air trapped in this hose makes it into the system)

Procedure if you don't have a vacuum or power bleeder.

1. check reservoir full.
2. open slave bleeder
3 press pedal slowly
4 close slave bleeder
5 repeat above 4 steps until fluid out of the bleeder is air free for 5 cycles.
Then you should be good to go.
Bob

[matteo92065]

I had some of these same problems with mine. For me it all came down to the length of the pushrod that goes from pedal linkage to clutch cylinder. It must be just the right length. Mine seemed like it was the right length, but would not take a bleed. After adjusting, it worked perfectly. I cant remember if I had it slightly too long or short.

[metros]

I have attempted to increase the amount that the master cylinder rod is pushing in. I adjust the rod longer and used a screwdriver instead of the clevis, same results.

I tried to push on the rod going to the master by hand and I couldn't get enough pressure on it to get full compression. I could only squish it an inch or two.

I'm going to double check my hardlines and make sure I don't have any odd bends that would trap air.

[xxguitarist]

We found it helped to clamp the Slave cyl compressed, then treat it like bleeding brakes, except using a screwdriver as a handle (more travel) on the Master instead of the pedal.

[matteo92065]

I have attempted to increase the amount that the master cylinder rod is pushing in. I adjust the rod longer and used a screwdriver instead of the clevis, same results.

I tried to push on the rod going to the master by hand and I couldn't get enough pressure on it to get full compression. I could only squish it an inch or two.

I'm going to double check my hardlines and make sure I don't have any odd bends that would trap air.

Is it possible it is too long?

[metros]

I started with it adjusted to the hole on clutch pedal lever perfectly. The clevis originally slid through both holes without any fuss.

[Hindsight]

My suggestion: Spend the money on the motive bleeder (ensuring you get the one with the right cap for Subaru/Ford, NOT the universal one-size-doesn't-fit-anything cap). It's not that expensive and you can get other caps to use it on other vehicles. REALLY speeds the job up. You can bleed things yourself with that setup.

[metros]

Think I've got this licked.

I stopped by STiPWRD's house to loan him my airlift coolant fill tool (awesome btw). I was able to check his pedal out and the feel of the clutch fork at rest. He ultimately made a solid suggestion that the air powered bleeding tool I was using may be pulling air from around the threads. I switched to a hand powered vacuum bleeder and repeated all of the regular steps. The pedal feel improved dramatically but still wasn't where it needed to be. I decided to really put a lot of pre-load on the master cylinder by unscrewing the clevis attachment almost all the way out. I used a screwdriver to connect the two and re-bled. That was the ticket. It now feels excellent and allows me to shift through the gears.

I did back off the pre-load a few threads before working the clevis back through the hole. I estimate that the master cylinder u joint is ~75% past the clutch pedal hole - for future builders, that's the amount of pre-load I have on my clutch pedal.

Anyone else confirm how much pre-load they have as being similar/more/less?

Glad I loaned a tool to another 818 builder. Ultimately helped me fix a stuck point.

[Bob_n_Cincy]

The service manual doesn't say to preload.
Actually it say to unload by 3/4 a turn of the shaft.

clutch.jpg

[metros]

I ended up removing most of the pre-load I had adjusted in. I have maybe 2-3 threads on the rod as pre-load. Clutch engagement feels as it should.

[STiPWRD]

Congrats, glad you got the clutch sorted! It definitely was more of a pain than expected.

[brian b 36]

i think that was what i told you to try it worked for me to glad you got it solved brian

[C.Plavan]

Mine was a B%^$% to bleed too.

[metros]

Agreed Brian, I'm going to remove all preload and see what it feels like.