Clarification on bleeding the clutch with Motive bleeder

[RJFabCab]

I just noticed in the DIY section that when bleeding the clutch, the instructions mention "pumping the pedal". Please help clarify the following:

"Open the clutch bleeder valve until clear, bubble free brake fluid emerges (at least 30 seconds according to Porsche). Remove the wood. Then, pump the pedal again very slowly by hand for a further 60 seconds. After pressing the pedal down fully about 10 to 15 times, leave the pedal in its normal position. After allowing a fill time of 90 seconds, check that no more air bubbles appear at the bleeder valve (use a collecting bottle with a transparent hose). Then close the bleeder valve. Wipe off the area and replace the rubber protective cap over the bleed screw.

You may notice that the clutch pedal does not return... so carefully pull it up (slowly) to it's normal position. Then depress it (slowly) a few (at lease 5) times. In a few cycles the feel should return"

Does this mean the following:

1. Motive bleeder is hooked up and pressurized.

2. The clutch pedal is fully depressed.

3. The clutch bleed valve is opened and then closed once bubble free fluid emerges.

4. The brake pedal is pumped very slowly by hand 10-15 times over the course of 60 seconds?

5. Wait 90 seconds, and then rebleed the clutch valve until bubble free fluid emerges. Close the clutch bleeder valve.

6. Slowly pull up the clutch pedal (I do it over about 1 minute) and then cycle the pedal slowly several times until the clutch pedal 'feel' returns.

7. Move on with bleeding the rest of the system.

This question arises because I don't remember the "pump the pedal" portion of the DIY instructions. I have had to rebleed my clutch on more than one occasion due to spongy feel related to air in the clutch only.

So, the brake pedal should be pumped while the system is under pressure (with the Motive bleeder) and the clutch bleeder valve is closed? Or, should the clutch bleeder valve be open while pumping the brake pedal and the system is pressurized?

The latter seems to make more sense.

Cheers

[Loren]

Yes, the clutch bleeding procedure was modified based on information in Porsche supplement 98 of the Carrera Service Manual ( I noted that at the top of the DIY).

1. Yes.

2. Yes.

3. Yes.

4. No. The clutch pedal is "slowly" pumped.

5. No. The bleed valve stays open during the process until no more air is seen emerging (about 90 seconds).

6. After closing the bleed valve, yes.

7. Correct.

So, the brake pedal should be pumped while the system is under pressure (with the Motive bleeder) and the clutch bleeder valve is closed? Or, should the clutch bleeder valve be open while pumping the brake pedal and the system is pressurized?

No, the brake pedal is not touched during this clutch bleeding process.

[RJFabCab]

Thanks, Loren!

I cut straight to the chase and missed the 'edited' line about the supplement #98.

Thanks for the clarification.

BTW, I'm ready to put together the DIY GT3 rotor post.

RJ

Edited July 30, 2006 by RJFabCab

[Stefan]

I had this same question on Saturday when I was bleeding the system and I agree with Loren's interpretation. You would never want to work the clutch pedal with the bleeder open as that would introduce air into the system.

I read "Open the clutch bleeder valve until clear, bubble free brake fluid emerges..."

as

"Open the clutch bleeder valve. When clear, bubble free brake fluid emerges, close the clutch bleeder valve."

I read the (similarly vague) "After allowing a fill time of 90 seconds, check that no more air bubbles appear at the bleeder valve"

as

"After bleeding for an additional 90 seconds, check that no more air bubbles appear at the bleeder valve"

---

Now, three days and several hundred miles later, the clutch still works great. (Slightly smoother than pre-bleed)

[smithk3933]

Just to be sure I understand the process, after the first bleed, the bleed valve is closed and then the clutch pedal is exercised for 60 seconds. Correct? Assume that you would not want to pump the pedal with the valve open.

Thanks.

This is on the top of my list of maintenance items for my new to me 02 C4S.

Keith