Lars87

This morning my Lt4 had no clutch, there is no spill underneath the car or anywhere. I topped the fluid off, since it was empty, and now the clutch is fine again...

Anyway, what is the rubber hatīs function inside my clutch reservoir cap? Is it supposed to look like this? IT dosent allow much fluid in the clutch reservoir like this...

Jitsu

I believe it acts as a seal to keep water from entering the hydraulic fluid system.

rocco16

That rubber hat is an expandable moisture barrier. It is designed to telescope/accordian into itself to take up a small volume when the clutch master cylinder is full, then expand as the fluid level drops.
You have to compress/telescope/accordian the seal when you put it back into the reservoir....play around with it a bit, you'll get it.

Almost all brake master cylinder reservoirs and clutch master cylinders have these devices and they all work on the same principal...

gixxr

check underneath your carpet, if its leaking your floor will be soaked with fluid

94z07fx3

The fluid level in brake master cylinder resivoirs drop as the pads wear but the clutch master cylinder resivoir fills as the clutch disk wears. That is why the hat on the clutch resivoir does not fold into the cap like the one on the brake. I made a mark on the resivoir when I replaced it so that I could easily find what level to fill to when the hat is out so that when the hat is back in the fluid comes to the full line.

Lars87

Dont you level the fluid to the "full" mark, then "curl" op the rubber hat, and put it back on with the cap???

94z07fx3

Nope. The hat is supposed to be fully deployed so that it has room to shrink. It's the reverse of the brake's hat operation.

Lars87

ok. That means that there is very little fluid in the resevoir then

94z07fx3

Oh yeah! The first time I bled a new slave I sucked that thing dry [1] a couple of times and had to start over. And that was with me filling it to the brim.

[1] Mity-Vac Clone.

AGENT 86

Beentheredunnit

rocco16

I think this is wrong, but it's been awhile since I bled my clutch system and I don't have access to my FMS at the moment to verify.
So, I can only say to fill the clutch master to the full mark, and collapse the rubber hat before installing it; it will then have room to move in both directions.


Larry
__________
not easily impressed....

94z07fx3

I trust ZF Doc. But you go ahead and blaze your own trail.

(Clicky)

rocco16

I blaze few trails, preferring to go by the Factory Service Manual.
Only filling the reservoir to below the low mark sounds like "blazing new trails" to me......I don't care who the person is playing Lewis and Clark.


Larry
__________
don't believe everything you hear....

94z07fx3

Kindly point me to the section of the FSM that says to over fill the resivoir using your method. I just read section 7C and it says nothing about compressing the moisture barrier with fluid to the fill line. You're making stuff up. That's ok with me. Just don't say it's from the FSM when it isn't.