Clutch Slave Bleeding Help
The circlip is a small wire clip (almost flat) that encircles the master cylinder push rod. This clip is what retains the rod once it is pushed into the end of the cylinder. It is tiny and is barely visible. In my opinion, the odds of even a seasoned mechanic removing this circlip while under the dash is about 1 in 100 !
The good news is you don't need to. To bleed the cylinder you have to move next onto the snap ring which retains the piston in the master cylinder and which prevents the piston from being extracted from the cylinder during normal operation.
It's about 5/8" in diameter and it is an internal snap ring. It is located at the end of the cylinder (the top side) and it also encircles the push rod too. This is all inside the square black plastic molded end of the master cylinder.
Using an internal snap ring tool you can, with fair difficulty, remove this small snap ring. Once removed, you can pull on the pushrod and then slowly extract the piston just enough to see fluid beginning to flow. Once you see that fluid, you re-insert the piston into the cylinder, and if you are lucky, all the air in the cylinder will have been displaced.
You may have to do this 2-3 times until all the air is purged or bled.
You are done bleeding when you only have 1/8" of stroke when pushing the rod into the cylinder. If you have more than 1/8" of movement or stroke, you still have air in the cylinder.
Once you have all the air bled from the master cylinder, you can move on to the normal process of bleeding the slave - using the slave bleed port on the side of the tranny.
The degree of difficulty of removing the master cylinder snap ring while under the dash is high. If you have trouble, you can loosen the master cylinder from its mounting bracket under the dash with a 1'4 turn.
After prying the cylinder pushrod end from the upper pedal linkage with a flat screw driver, you can then push the master cylinder and pushrod through the firewall for better access and visibility. (After prying loose the rubber firewall gromet.) You need to loosen the clutch hydraulic reservoir and the black plastic rectangular box beside it. Once you have those moved out of the way you can pull up on the master cylinder and then will be able to see it, and get to that pesky snap ring.
At this time, the clutch master cylinder will still have all lines attached and you can hold it upright, just to the left of the brake master cylinder which is mounted on the firewall. (this is as you face the front of the truck)
This process amounts to a bench bleeding of your master cylinder. The only place the air can still hide is in the line going to the slave, or in the slave cylinder itself. Normal bleeding should clear this, Some guys do gravity bleeding to clear this, but no matter the process, make sure your reservoir never goes dry in the process!
good Luck, because you will need it!
A better (but more time consuming) way to "burp" the clutch hydraulic system is to remove the whole thing, strap it to a bench using wire ties, and remove the air. I just had to do this after a master cylinder replacement because the mechanic did not properly remove the air (might as well have done it myself).
The steps were as follows:
1) Remove the line to the slave cylinder on the transmission (it is sealed so does not leak when removed). There is a plastic ring already on the connector that functions as a "fuel line tool". Simply push it toward the transmission and it should release the connector.
2) Remove the clutch pedal from the master cylinder rod.
3) Turn the master cylinder with a pair or vise grips (or with a wrench from inside the engine compartment) until it is loose.
4) Disconnect the resovior from the power box (which you will need to unbolt from the firewall to access the back of the master cylinder)
5) Pull the entire system out of the truck. Take care to get the slave cylinder line out of the vehicle since it has some bends in it.
6) Strap it to a bench and follow the instructions in this video.
The whole thing took me about 90 minutes, mostly because my 2 helpers were 12 and 10, but the clutch works like a champ now.
Inside the cab, remove the starter interlock from around the clutch pedal connecting rod, disconnect the other end of the clutch pedal connecting rod from the pedal arm (a body panel pry tool worked well on my '94). There is an internal snap ring inside the master cylinder housing over the piston. Remove the internal snap ring & use the connecting rod to pull the MC's piston up till just the air and a little fluid escapes (use a container or shop rags to catch the bit of spilled fluid), & pump the master a couple of strokes. Repeat the above, reassemble then bleed per the manual, open the bleeder and let gravity bleed. Might have to bleed the bleeder a couple of times, biggest thing is the air in the master.
Make sure the reservoir stays full of fluid when bleeding the system.
It actually got better on its own to where it would drive OK, but there would still be a scraping/groaning sound when I pushed in the clutch pedal. It was like the clutch was not completely disengaging. I figured it had to be the MC, plus I think I found a little fluid on its housing, so I bought & installed another MC. I even bench bled it before gravity bleeding the slave cyl. Did it 2X, but I'm still getting the scraping/groaning sound even though the clutch pedal felt good and firm after bench bleeding.
Last edited by mrau92me; May 1, 2013 at 02:06 PM. Reason: Added missing spaces (copy & paste glitch, I guess)
Anyway, fluid gushed out the 2ndtime, but after putting the snap ring back on, when I pushed in on the piston acouple times, to check the firmness of it, it was firm, but a little fluid cameout when the piston rod returned the short distance. Do I have a problem, or is that just residualfluid from performing this procedure?
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