I have read other problems where the clutch pedal sticks to the floor, but mine is doing something really strange. It will function normally if i press it hard and quick but if I press it slowly or just rest my foot on it before I make my shift, it will sink to the floor and stick. Has anyone else had their pedal to do this? I installed new fluid and a s.s. clutch line before I went to Deal's Gap and everything worked flawless up there. This didn't start till yesterday. Any help would be appreciated.

 

If there is no external leakage, it sounds like the master cylinder is leaking internally, either past the piston or the check valve. A change to a different type of fluid can cause the seal to shrink and leakage to occur.

If there is external leakage that should pinpoint the problem.

 

Yep, your master cylinder is starting to die. If you quickly change gears, it will be fine as the hydraulic pressure won't have time to leak past the seal. When you hold it down, the hydraulic pressure slowly bleeds off through the bad seal.

Change it now before it gets worse - when hydraulics start to go, they will soon go totally and you'll have nothing left of your master cylinder. Buy a BRAND NEW master cylinder, don't try and rebuild it or anything.

Dale

 

Yup, I had the same prob and I replaced the master. I got it from Ray Crowe for about $70. works fine now

 

If it's not one thing going wrong it's another.

 

What about the brake master cylinder? Will a different type of fluid affect that seal?

 

The clutch and brake master share the same fluid reservoir. If it's safe for the brake master, it's safe for the clutch master.

Dale

 

Yeah but, if changing to a different type of fluid caused the clutch master cylinder seal to shrink/leak, would it also cause the brake master cylinder to shrink/leak as well?

 

It could, but the clutch seal sees a lot more motion and wear during normal use. The wear is what really caused the leak - the fluid change was just the last straw.

Some brake fluids also have more lubricity than others, leading to longer seal life, especially in the clutch. Castrol/Girling LMA is one of the best, while some of the extremely high-performance fluids are not very good in this respect.

 

What about ATE Super Blue? That's what I used.

 

I'm sorry - I've never used it, so I don't know. I've also heard that the new Valvoline synthetic fluid is very good, but I have no 1st-hand experience with that. I've always used the LMA in my FD and racecars.

Maybe someone else can chime in here...

 

Super Blue ATE is fine.

 

Just ordered a CMC from Malloy.

 

Yea!!! It's fixed!!! Took all of 15 mins to install. Had to make a new gasket for the firewall opening. Took longer to bleed than it did to install that sucker!!!

 

ATE Blue or Amber (Type 200) works as good as anything on the market. Great heat resistance/ higher boiling points and low hygroscopicity.