Tech Support- Clutch slave bleed
09-18-2018, 01:44 PM
#16
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Thread Starter
Not even the first time Ahsai. I fully expected to lift the pedal up and have full pressure. 30+ times and 5 methods later, still nothing.. Ordered parts, that's all I know how to do at this point. No leaks, baffling.
09-18-2018, 02:25 PM
#18
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Haven't removed it since. Might be worth a try. But at this point if I have to remove the mc (or slave again) I'll just replace them. MC looks like it's going to make me suffer a bit.
09-18-2018, 03:41 PM
#19
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I had a similar issue when I had to bleed my clutch. It took me several times to get it to pressure. Here is what I did:
1. Use a pressure bleeder, max 20psi
2. Do not overfill the master cylinder
3. Use a bar or something and press the clutch down all the way, and hold it there
4. Bleed the clutch fluid out at the slave cylinder. Let it run for at least 30 seconds.
5. Close the bleeder valve
6. Release pressure on the pressure bleeder
7. Release the clutch. If clutch is not up to pressure, repeat this process.
I had to do this 3 times before I got rid of the air bubble and it got up to pressure. I used 2 liters of fluid, the first one did a complete flush, and when I got to the second one I caught the fluid from the slave clutch into a clean container and re-used it in the pressure bleeder.
1. Use a pressure bleeder, max 20psi
2. Do not overfill the master cylinder
3. Use a bar or something and press the clutch down all the way, and hold it there
4. Bleed the clutch fluid out at the slave cylinder. Let it run for at least 30 seconds.
5. Close the bleeder valve
6. Release pressure on the pressure bleeder
7. Release the clutch. If clutch is not up to pressure, repeat this process.
I had to do this 3 times before I got rid of the air bubble and it got up to pressure. I used 2 liters of fluid, the first one did a complete flush, and when I got to the second one I caught the fluid from the slave clutch into a clean container and re-used it in the pressure bleeder.
Can someone explain the reason for step 3? If the clutch master cylinder is anything like the brake master cylinder, depressing the pedal cuts off the reservoir from the hydraulic circuit, so the pressure bleeder cannot force fluid down to the slave cylinder. Or am I missing something?
thanks
09-18-2018, 03:51 PM
#20
Rennlist Member
Nope. Every time I have seen these symptoms after slave cylinder R&R it has been due to the push rod missing the indentation of the release fork. I have seen the push rod cocked in there in a way that it didn't blow the piston and seal out of it though. It usually blows the retaining clip , piston and seal out from repeated pumping.
Are you sure you have installed all compatible components? A failure of the slave or master cylinder at the exact moment you put it back together is highly unlikely, but there is a first time for every thing.
Are you sure you have installed all compatible components? A failure of the slave or master cylinder at the exact moment you put it back together is highly unlikely, but there is a first time for every thing.
09-18-2018, 04:14 PM
#21
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Thread Starter
Yes, I have high confidence that the slave is installed correctly. The clutch arm was right there shiny new (OEM) in the opening. I had the trans and motor lowered and was on a lift at eye level when installed. It looked like it would be hard to miss the indent with the rod. When I missed with my M3, it made a noise, pedal had pressure, then went to the floor, then fluid on the ground.
My gut is telling me the mc isn't pushing. I'll know when I replace it, and slave if I'm going crazy or not.
My gut is telling me the mc isn't pushing. I'll know when I replace it, and slave if I'm going crazy or not.
09-18-2018, 04:18 PM
#22
09-18-2018, 04:27 PM
#23
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Thread Starter
I agree as well.
09-18-2018, 04:27 PM
#24
When I was bleeding my clutch slave cylinder, I didn't do step 3, and it seemed to work fine: clear fluid came out, then some air bubbles came out, and finally only clear fluid came out.
Can someone explain the reason for step 3? If the clutch master cylinder is anything like the brake master cylinder, depressing the pedal cuts off the reservoir from the hydraulic circuit, so the pressure bleeder cannot force fluid down to the slave cylinder. Or am I missing something?
Can someone explain the reason for step 3? If the clutch master cylinder is anything like the brake master cylinder, depressing the pedal cuts off the reservoir from the hydraulic circuit, so the pressure bleeder cannot force fluid down to the slave cylinder. Or am I missing something?
I did see a lot of air bubble coming out, but some of that was leaking by the bleeder valve vs. coming out from the line. I found it to be about 1/8 of a turn between being open enough to bleed and too much to let air back into the bleeder screw.
