Cant get new slave cylinder to activate

I just did a complete new clutch system including new slave cylinder & spent more then 1 hr triing to bleed the First slave cylinder & figuredit to be defective so out came the tranny again & purchased a another new slave cylinder from different parts store ,but still the same exact slave cylinder & spent more then 2 hrs triing to get this 2nd one to disengage the pressure plate & still nothing & this was following the direction from the Library for the 2nd slave cyl. & with the patience's of my girl friend as an asst.

Any help would be nice. I was thinking of going to have it pressure bled at a shop

Did you invert the master cylinder? Did you bench bleed the slave before installation?

a vacuum pump works good for this. you can get one at autozone

The slave cylinder is internal & has a special quick disconnect line so it cant be bench bled.

I was wondering about the vacuum pump method or having it pressure bled.

I'll check out autozone,Thanks

I'm aware, but you can remove the master from the vehicle and bleed it on the bench while the trans it out of the vehicle. Then re-install it. It helps to invert the master, to get the trapped air out. But this can be done in the vehicle as well.

Try reverse bleeding it with the master cylinder unmounted from the firewall but the fluid line still connected. By reverse bleeding I mean force fluid up through the bleeder screw with a turkey baster or bulb type syringe connected to the bleeder via a piece of vacuum hose. Also it's important to keep the clutch master completely level so any air trapped can escape.

Just so you know...these systems are close to being considered a 'self-bleed' system. Get it initially bled by opening the bleeder til it's solid fluid coming out. Then pump the pedal like 10 times slowly, then hold it to the floor, open bleeder(should squirt so watch the eyes) then close it. pump like crazy but not violently. Then go for a drive. They're designed to be self-bled and you'll notice it'll work better and better the more you drive it. I've had a few slaves do that.

I'd start to suspect a bad master if that doesn't work.


For what it's worth, I just put in a Saches slave and found out it was full of fluid already....quick coupling conected, then drove it without bleeding. I've been told this is becoming common practice on some parts(like slave cyls)

the master cylinder was never a problem before I started the new clutch job along with the new slave cylinder. With the master still bolted to the firewall I had an extra fluid line hooked to the master & the other end ,the quick disconnect has been cut off to allow me to clamp a clear section of tubing to the fluid line to allow me to basically bench bleed it back into the resevoir. I got all the air out of the master then I would clamp the resevoir to master cylinder hose & then remove bleeder hose & install fluid hose going to slave cylinder.

With g/f in truck pumping on the pedal 10 times I then inserted a small phillips screwdriver into end of hose to release any air that would of been in the hose.

Then I went to hook it up via the quick connect tothe slave cylinder & then with a long section of clear tubing I would put on end on the slave cylinder bleeder valve & the other end I stuck up into the engine bay & set into the resevoir to bleed the hole system.

once I opened the bleeder valve on the slave cylinder any pressure that was there from previous bleeding was now gone.

I've been ready to pull my hair out cause I cant figure out the problem & need the truck back ASAP for firewood gathering in the amount of 10-15 truck loads of Douglas Fir & 3 truck loads of Oak & to help move a friend this weekend.

A tranny shop said that with the master bleed completely & then hook up the fluid line going to the slave cylinder ,he said that the pedal should be completely stiff if its a good master cylinder due to the quick disconnect check valve.

This stiffness I have never had even after bench bleeding the master while it was still on the firewall.

Ive also seen about inverting the master cylinder ,but also saw about making sure the master cylinder is level,How due you make it level when its bolted to the firewall at an angle?

Maybe the master did go bad ,but why would it do it while the tranny was out as I said theres never been a problem with shifing, before I did the clutch job.

What would you guys think about a temperory use of a bone yard master cylinder due to the cost of a new one,between paychecks?

Whats the difference between the 4 cyl master & the 6 cyl master? Autozone & Schucks/O'Reilly's list a different part # but have both for thew same price?

Due to the angle of the master cyl the ONLY way to remove all the air is to remove the master cyl. The tube end has to be higher than the rod end. Hand pump the rod slowly with the quick connect DISCONNECTED from the slave cyl. When the master cyl rod moves less than 1/8" all the air is gone from the master cyl and lines. Then remount the master cyl and connect the quick connect to the slave cyl. Push the clutch pedal slowly. If no resistance is felt you need to bleed the slave cyl. When bleeding the slave push pedal down slow and hold then open and close bleeder then release pedal.Make sure the reservoir does not get low. Repeat until no air is seen. NOTE: Rapid pumping causes the fluid to aireate and you will have to start over.

Should the line going to the slave cylinder that has the quick disconnect still be connected to the master cylinder when bench bleeding it? I thought that I could use a section from a donor truck with out the quick disconnect & attach a section of clear tubing to it & have it going into the resevoir,But I did not have the master removed from the truck .So I guesss back to the grind I go man this is getting to be a pain. I really dont want to have to take it to a shop for $90-155 just for them to bleed the system.

It's far easier if you remove the master + line from the truck, thus the "bench" in "bench bleeding" . Yes, the line stays connected to the master.

great sounds like i'll be finally getting it on the road soon

ITS FINISHED YES YES YES _cheers:
Now I can go finish getting my 10+ truck loads of fir & oak.

Thanks guys for all your input ,the key issue was to keep the fluid line going to the slave cylinder connected to the master cyl ,but disconnect from the slaves quick disconnect.

Glad I wont be doing this for a long time,but if I ever do it again I now know the little secret.