luisimo

I had read the process by many people and most mentioned that they follow the instructions on renntech.org

http://www.renntech.org/forums/index.php?showtopic=7064

But what is confusing to me is that a Motive Power Bleeder is used for the brake bleeding and a manual process is noted for the clutch.

Can the Clutch be bleed with a Motive Power Bleeder?

I just did my brakes and would like to do the clutch but I don't have an assistant and I don't want to mess anything trying to do it with the Motive Power Bleeder.

Edgy01

Find an assistant. It's far easier than anything else. Simply have them in the seat, guarding the clutch pedal from falling to the firewall, as they go through the pumping motions. Here's the spot on the rear:

JW911

I did it without an assistant. It was two years ago so I don't recall exactly how I did it. But I followed the instructions, then opened the bleed valve and the power bleeder did the rest.

FYI, that bleeder valve is a %$$# to reach and get with a wrench. And as I recall, the size was not the same as the Renntech directions. If my memory serves me, it is 11 mm.

1999Porsche911

Yes. Pressurize motive, depress pedal to floor and hold with a stick or other device. Bleed the clutch. You're done.

luisimo

Thank you guys for the follow up, Edgy01 special thanks for the pictures. Going to recruit a 'volunteer' and get it done today.

Mark Hubley

Why would you depress the clutch pedal? Doesn't depressing the pedal block the pathway between the reservoir and the slave cylinder.

I've used the power bleeder to flush the clutch lines on my Boxster and 944, and I've done it with the clutch pedal left alone.

atr911

Just did this and can confirm that depressing the clutch is not required.

Pressurize the bottle and open the valve. Not as hard to get to as many have suggested however I did have my car on a hoist which gave reasonably easy access.

obsessedone

Porsche recommends putting pedal to floor as design and orientation of master or operating cylinder can trap some old fluid and any air that is the master cylinder. With the pedal depressed the master cylinder piston moves full travel in the cylinder evacuating old fluid and any air from cylinder into lines so you can push them out slave cylinder bleeder as you bleed. Not usually a big deal unless you have disassembled system or gotten air in master by letting resevoir get low during bleeding. Keep in mind clutch line is only about 1/3 from top of resevoir to prevent clutch hydraulic leak from draining brake resevoir - so keep fluid above this level while bleeding clutch or you will get air in the clutch lines even though resevoir is nearly 2/3 full.

Mark Hubley

I can understand pushing on the clutch pedal to clear out some fluid from the master cylinder. Here's where I am confused:

I have read posts where people say that the clutch pedal should remain depressed during the entire clutch-flushing operation. That doesn't make sense to me. Consider that I can step on the clutch pedal and keep the clutch disengaged from the flywheel. Thus, it seems to me that when the clutch pedal is fully depressed, the path from the reservoir to the slave cylinder must be closed. Otherwise, pressure from the master cylinder would be lost to the reservoir and the clutch would not disengage. If the pedal is fully depressed, and the path between the reservoir and slave cylinder is, indeed, closed, then how can you flush the system with the clutch pedal depressed?

I'm not so much trying to argue the point. Rather, I'm hoping someone can explain what is going on.

I went down this path in a thread on Porsche Pete's Boxster Board, and the responses made more-or-less the following point: the pedal should be fully depressed during the entire procedure, we know what's best, don't expect an explanation, don't question us.

Maybe the only way I'll get an explanation is with a visit to Stuttgart???

obsessedone

Good question. If you bleed with pedal depressed as recommended fluid does indeed flow, so it seems the clutch master cylinder ports/valving is set up differently than a brake master. A diagram would certainly help with understanding how this works.