Dayde

So, I had a leak somewhere in the system, and installed a new master cylinder, line, and slave. I had trouble removing the clutch line (I couldn't get to the retaining bolt under the PBR, and left the line in place... shoved into the chassis for now). I bought a Mityvac, and bench bled the master cylinder, put plumbing tape on the slave's bleeder valve, as well as on the master cylinder clutch line fitting, and assembled the system. However, I am unable to bleed it. I am using the mityvac to build up negative pressure, then opening the bleeder valve a little, and then repeating the process. I have done this process at least 15 times, and am still getting alot of air bubbles. Is there something I am missing? The front of the car is elevated on jack stands... could that cause a problem? If so, why?

Thanks in advance.

HlhnEast

You seem to be doing everything right. I just did my clutch hydraulics and it took quite a bit of bleeding to work out the bubbles but I think the 4+3 system is easier than the ZF. Try just leaving the bleeder cracked, keep the negative pressure up and keep feeding the fluid to it. Check your connection at the bleeder from the MitiVac is solid. I bought a cheap vac pump from HF and the connector adapters did not work well so I popped the rubber line over the bleeder with better results. Still took a while.

Good luck!

Aaron71771

Do you have the slave off the car? It needs to be vertical with the bleed valve at the highest point. zfdoc's web site has some tips on bleeding the system, you may want to check them out.

Also, lightly pump your clutch pedal 100 times or so to work out all the air from the master.

GREGGPENN

At least that many times!

I had to tilt the entire car (using jacks) then pump and pump and pump until I finally didn't get bubbles any more. Part of my issue was not being able to get the front end of the car high enough. That was due to low ceiling clearance and needing to have the hood open.

Z51JEFF

When I did mine no amount of pumping would work.What I did was took a Mityvac,reconfigured it to pump fluid up through the salve to the MC.Put the thing together with the various fitting,fill the Mityvac canister with fluid and go at it.

Dayde

That is probably my problem. I have the slave on the car. Thanks for the help.

Dayde

I definitely have my front end high enough. It's jacked up in the front, in my driveway (garage is full of wife's stuff :p). So, I guess the car doesn't need to be level...

Dayde

That sounds like the best approach. How do you reconfigure the mityvac to pump fluid instead of create vacuum? I looked through the manual and didn't see anything..

Thanks

GREGGPENN

Because of the bends in the connective line, you could also try raising the rear, pump until bubbles are gone, level car, repeat, and return to front end high.

Deepa

I had a syringe that fit snugly in the bleeder screw of the slave cylinder. Put the brake fluid in the syringe, put the syringe tip in the bleeder hole, open bleeder, squirt in fluid, close bleeder, repeat.

If you are careful, you do not get any air in the system. Pedal went from soft as all hell to perfect in under 5 minutes. It did take 2 people to do, but it was not working the normal way.

Dayde

Thanks alot for all the help, everyone.

Anyone replace the clutch line by chance? I am at a loss figuring out how to get to the bolt holding it in place. I tried removing the catalytic converter to try reaching it from that direction, but sheered off the bolt (it was pretty stuck, I guess). So, I tucked the existing clutch line into the chassis for now, but I can't leave it that way for long.

Z51JEFF

Find the port that pumps and hook the line to that.I didn't use the manual to hook up the hoses,I just figured if it sucks its got to have an exhaust port.There are enough fittings to make this work.I went and got some clear hose that was long enough that I didn't have to lay under the car while doing this.I zip tied the clear hose to the fittings so it wouldn't come off.

Dayde

Thanks. The Mityvac I bought doesn't seem to have that port. It does have a fancy gauge on it, that I really don't need :p

Dayde

Well, thanks everyone for the help! I finally got my clutch going again.. still need to remove the old line though.

Removing the slave and bleeding it a bunch of times, then some more, and pumping the clutch about 200 times seemed to do the trick. I still have some air trapped in there, as the clutch isn't 100% but perfectly drivable (a little hard getting into 1st and reverse). I think I will just bleed it again after driving on it a few days to a week to work out any air trapped in there.

One thing I realized I was doing wrong: I wasn't opening the bleed valve enough, which was really making it take 10 times longer. I was opening it about 1/8 turn, and had better luck at 1/4 turn. Using the Mityvac at about 15-20 pumps, I could use it 2-3 times before refilling the master cylinder.

Z51JEFF

I need a new gauge,want to sell it?

Dayde

Thanks, but I will hold onto mine. It could come in handy for vacuum testing at some point. Just not really necessary for bleeding I guess.


http://cgi.ebay.com/Mityvac-Replacem...#ht_1817wt_789

richauto

I have seen this problem on other hydralic clutch systems. Try to reverse bleed the system. Open the bleeder and the top of the clutch master, slowly push fluid through the bleeder and watch for air in the master cylinder. Continue until there is no more air. You can purchase reverse bleeder tool. Hope this helps.

Dayde

I'm feeling pretty special right now. Last night, I decided to finish bleeding the clutch, and get it working 100%. During the process, I misjudged how much fluid had been bled out, and let the master cylinder get empty. So, it sucked in a bunch of air, and I started the process all over again.

Now I have a different problem... while bleeding the system, I stopped getting any fluid, and instead the system almost holds the vacuum. It takes about 30 minutes for the Mityvac to come all the way down in vacuum. There is definitely air moving in the tube, but I have done this now about a dozen times with still no fluid. I know there can't be a blockage of any kind, and I made sure the bleeder screw was clean as well. Any thoughts? I wish I bought a Phoenix reverse bleeder instead of the Mityvac. The Mityvac I bought is apparently one of the few unites with no pressure/pump option.

Dayde

I'm feeling a little better right now. After getting a fluid transfer hand pump and reverse bleeding the clutch, I was still running into problems. So, I removed the slave to vacuum bleed it some more and noticed the slave internals were separated from the housing. So, maybe all this trouble is due to a defective unit...

Dayde

I have fully bled a replacement slave, reinstalled it, and pumped the clutch pedal about 400 times. The pedal is firm, maybe even too hard... but there is still no clutch (i.e. I cannot put the transmission in gear with the clutch depressed). The pedal has no pressure for the first 1-2 inches, and then is almost as hard as the brake pedal for teh remainder of travel. Could I have damaged the master cylinder somehow using the Mityvac? Or does that sounds like something else now? I had this working at one point, so I do not know what the deal is now.