Drove the car all day, then it cooled down and i needed to bleed the clutch.

[David T]

It isn't a check valve per se -- it's a rubber tipped stopper that seals off the reservoir so that fluid is forced out to the slave cylinder rather than back into the reservoir. Tell tale sign of that stopper going bad is fluid shooting out the breather hole in the reservoir cap.

Attachment 41594

Bill Robertson
#5939

From the sounds of your problem the clutch itself is OK, there is a problem with the master cylinder or the slave cylinder. If the slave is not leaking and you have the S/S line the only thing left is the clutch master cylinder. Flush with fresh fluid and bleed well. If that doesn't fix the problem replace or rebuild the clutch master cylinder. If the hose between the reservoir and master cylinder is "sweating" replace it too.

[Bitsyncmaster]

It isn't a check valve per se -- it's a rubber tipped stopper that seals off the reservoir so that fluid is forced out to the slave cylinder rather than back into the reservoir. Tell tale sign of that stopper going bad is fluid shooting out the breather hole in the reservoir cap.

Attachment 41594

Bill Robertson
#5939

I did the rebuild on my clutch master. Did that because I was seeing some leakage where the shaft to the pedal is. The rebuild seems to have fixed that.

Do you have the upgraded clutch line (hose)?

[Some guy]

I have the Stainless steal clutch line. the master and slave cylinder are only 5 and 4 years old.

i will try replacing the fluid, and see if that helps.

Is there any way the "check valve" in the master cylinder can be clogged?

[DMCMW Dave]

I have the Stainless steal clutch line. the master and slave cylinder are only 5 and 4 years old.

i will try replacing the fluid, and see if that helps.

Is there any way the "check valve" in the master cylinder can be clogged?

Any chance you have an adjustable link on the clutch pedal?

[Some guy]

I never adjusted the linkage on the clutch petal. it is an old car, so it could be done by the previous owner.

From what i can see, you press the petal down and the bar going into the master cylinder will go from a "loose fit" to finding the center on the plunger in side the master cylinder.

i am going to take off the rubber dust cover and see if the plunger resetting all the way back to the lock ring.

[content22207_2]

Again, the reservoir shutoff isn't really a valve -- it's a rod with a rubber tip:

ClutchMasterReservoirShutoff.jpg

When you move the piston it presses against the reservoir inlet, sealing it off. The piston is hollow so it slides over the rod as it continues towards the back of the cylinder.

Bill Robertson
#5939

[Some guy]

So it happened again this weekend. I drove it, and the next day the clutch was limp.

I took the clutch master cylinder apart and cleaned it.

I think it was binding inside the sleeve and not coming all the way out. i had to slam it on a wood table to get the piston out.

So after inspecting it, it all looked good as new. Putting it back together I used lithium grease and it was still hard to push in. Once i added a little brake fluid to the rubber o rings, then it worked.

Now it is much smoother, and i am getting fluid pushed back in to the reservoir.(Just a little when the clutch is starting to be depressed)

[Some guy]

I just replaced the O ring by my slave cylinder. It was copper and i replaced it with a newer copper washer.

If this doesn't work, i was thinking about using DOT 5.1 break fluid.

My problem is when the car gets hot, so i was thinking it would be better to have brake fluid that can handle heat better.

[David T]

I just replaced the O ring by my slave cylinder. It was copper and i replaced it with a newer copper washer.

If this doesn't work, i was thinking about using DOT 5.1 break fluid.

My problem is when the car gets hot, so i was thinking it would be better to have brake fluid that can handle heat better.

Although DOT 5 may handle the heat better it is compressible because you cannot get all of the tiny air bubbles out of it so you would get a lousey pedal. Only guessing here but it sounds like the old fluid had some water in it and it boiled when it got hot. A flush and refill of fresh DOT 4 ought to cure it. Make sure the hose and piping for the clutch is not close to any exhaust pipes.

[Some guy]

So Again it happened today, i could not make it around the block before the DAM clutch lost pressure,or sucked air. I had the clutch feeling perfect cold, and as soon as it warms up. it just lost pressure.

I am going to remove the Special T Clutch Bleeder tonight, and see if that is my problem.

I am just hitting my head against the wall trying to find an issue with something that has all new parts.