TR6

I'm trying to flush my hydraulics with new fluid. Brakes went fine. Plenty of brake pedal pressure now. Clutch was going well up to a point and then all went south. I started to get clutch pressure at one point. Pumped the clutch pedal and it was about 75% there in terms of pedal feel. So I bled some more. Now , I'm just getting nothing but air out of the bleed nipple. The reservoir has plenty of fluid in it and it never went empty. The fluid level is about 3/4 between the min and max marks on the reservoir. I'm using the motive bleeder, but all its doing now is bleeding air out of the clutch nipple until the motive is down to 5 or 10 lbs. Then I pump it up to 20 lbs again and repeat the process. Open the clutch bleeder and nothing but air comes out. What the heck am I doing wrong? Clutch pedal now has zero pressure and falls to the floor.

garrett376

How did you jack up your car - butt way up in the air? If so your reservoir can be slanted so no more fluid gets into the clutch portion... You sound like you're doing it all correctly (but don't pump the pedal if the pressure bleeder is attached) but you just don't have any fluid in the clutch portion despite the rest of the reservoir appearing full...

TR6

Car is level. However, I did pump the clutch pedal while the motive bleeder was attached (to see if it was firm). What did I do to it?

deep_uv

Assuming and hoping you didn't mess anything up with the clutch pumping......

I'd fill the reservoir to full before pressurizing. Maybe your fluid level is low enough to allow air into the intake of the clutch system which resides higher in the reservoir than the brake system's intake. That's the only way you could be blowing air past the fluid. One reason I'm a fan of the "wet" method when brake bleeding. Now go get another bottle of that fancy schmancy brake fluid and start over.

garrett376

I've never done it on a 964, but did it on an old 911 - the fill tube gets blown out of the master cylinder since the fill tube is a press fit. If I were you I'd check the pedal cluster - remove the wood panel and make sure the fill tube is still installed on the clutch master cylinder, and you don't have a big puddle!

But, based on the fact you get air blowing out of the slave cylinder, it sounds to me like your reservoir does not have any fluid in it... as Steve says, undo it all and start over...

deep_uv

Now we're going to have to take his bleeder away too.

TR6

I did pull up the floor to inspect the master cylinder and all there is dry. I also have the overflow line clamped off.

You guys may be right. A picture's worth a 1000 words, as they say. Is this too low to keep air out of the clutch line? If so, there's nothing I can do until I go buy some more Castrol SRF to add more.

chris walrod

Bingo, that is what the problem is. Bleed the clutch with the reservoir COMPLETELY full to the brim. Refill each bleed cycle. I dont use my Motive wet because I hate cleaning the thing out

The clutch circuit pickup in the reservoir is located higher than the brake master cylinder bleed for safety reasons.

No worries, get some more fluid and top her off. It may take four or so bleed cycles to get the air out. The good news is you KNOW that ALL of the old fluid is out.

deep_uv

Yup, run over to Walmart and get you a new bottle of SRF and you're all set.

TR6

Thanks Chris! I'll do that.
Walmart... That's good. They must keep the SRF next to the STP...

TR6

Update: Problem solved. You were right. The whole issue was the fluid level was too low in the reservoir. As soon as I added a little to fill it and started bleeding, immediately, I started getting fluid flowing again. It appears to be bled now and I have a solid clutch pedal. And the good news is that all of the fluid coming out of the bleed nipples is fresh SRF. So I'd say it was a thorough flush. It only cost me about $170 in SRF (2 bottles). Of course, I have a partial bottle of SRF left over....