Thread: Inrermittent clutch problem 120"

Originally Posted by Rangier Rover

At random.... Few times a day and some times once a week my ctutch hits the floor and next stroke is 100%. No leaks and no lost fluid. I'm changing the fluid as soon as I get time. Any one had this happen? What was the out come?

Thanks Tony

Probably clutch master cylinder - centre valve in it leaking sometimes. Could be some dirt in it and you might get it out by bleeding, but you would have to be lucky. Not much else it could be.

John

Originally Posted by JDNSW

Probably clutch master cylinder - centre valve in it leaking sometimes. Could be some dirt in it and you might get it out by bleeding, but you would have to be lucky. Not much else it could be.

John

Thanks John, I was thinking a valve as is internal problem. I will bleed and try it if no better I guess it comes apart.
Tony

I had this happen in my IIA. It would only happen once the engine was quite warm. I put it down to water in the fluid that was boiling. Changed the fluid and it never happened again.

Another option is the valve in the MC sticking open, and all the pressure going back into the reservoir.

IME, it is best to replace the clutch cylinders in pairs, as one will die shortly after the other.

Originally Posted by isuzurover

I had this happen in my IIA. It would only happen once the engine was quite warm. I put it down to water in the fluid that was boiling. Changed the fluid and it never happened again.

Another option is the valve in the MC sticking open, and all the pressure going back into the reservoir.

IME, it is best to replace the clutch cylinders in pairs, as one will die shortly after the other.

Come to think of it... Mine seems to do it around 20 mins after a long run. Seems heat is the trigger.
Tony

While boiling fluid is a possibility, I think it is fairly unlikely (although the slave cylinder is close to the exhaust) unless the fluid is grossly contaminated with water. Not like brakes where the wheel cylinders can get really hot. And the sudden recovery is not very likely either if that were the problem.

John

I had a similar problem a few years ago, the master cylinder was forcing the fluid out the breather in the cap. Changed master cylinder and fixed the problem.

cheers
Adrian

There's a little valve/seal right down the guts of the MC on the end of the push rod. Bits of crap in the fluid can foul it.
These MC's are a very common unit, I think they're even the same as you use on a trailer. Usually not worth mucking around with them as they're pretty cheap for a new unit, about $45.

Originally Posted by rijidij

There's a little valve/seal right down the guts of the MC on the end of the push rod. Bits of crap in the fluid can foul it.
These MC's are a very common unit, I think they're even the same as you use on a trailer. Usually not worth mucking around with them as they're pretty cheap for a new unit, about $45.

As Murray says, it is a 3/4" bore trailer master cyl, about $45. I agree that this is more than likely the problem, but I would suggest NOT to bleed it out, as it may fail altogether. Wait until you have the new one in your hands before touching the old one.

JC