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jlaird

jlaird

Great Pumpkin
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Car up on blocks in the front. Top off the MS and emptyed clutch side. Clutch tube removed at both ends and plastic tubeing affixed. Stubby installed on MC chutch side, some fluid replaced and pumped a couple of time to make sure it is clear.

Just about time to hit the tubeing with some air.
 
Adnausum, Jeff.

Pulled the master side clyinder out, found three of the small holes in the piston with crap in them and also a bit of crap when I pumped out the MC into a bucket with a towel in the bottom. The tube to the slave seemed clear.

Now, there are two holes in the MC from the top into the piston chamber. One large and one small, the large to the front of the car. It looks like the small one charges the piston/line and the large one is a bypass for what ever gets by the piston seal??

No clue what to do else. Nor any real idea as to just exactly where the piston should be in relation to the holes when put back together. However, at rest I think both of those holes should be open to the piston chamber ie not covered.

Seem right??

Intresting how that works when you think about it, simple, it just moves a fluid column back and forth unlike the brake side which has pressure on it all the time. No wonder it can be difficult to bleed.
 
Noop, no check valve in there. Hehe, I thought of that as well. I have done that and you know it right away.

Brakes are just fine, in fact great.
 
Well, off to put things back together now, then will have wife pump while I bleed. Later.
 
Now ready for my pumper but she is not. sigh.
 
All done. However, is still about the same.

The only thing I can think of now is that the throwout bearing was thiner on this clutch set than the old one that was bought seperate.

Any thing up around 4K and above and the pedal just goes way low and will not pump up. Slow down and all is fine.

Guess it is an engine saveing feature.

At least I know all is well in the MC and tube, no dirt.
 
I guess you really don't need this, since your last post Jack, but I thought I would post it as referrence anyway. This is not our MC, but the internals should be pretty universal! Not how the holes in the bottom of the chamber line up with the piston!
 

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Jack, Is the clutch disk the same thickness as when the clutch worked properly and is the pressure plate the same. Since this is a dynamic change caused by the variation in RPM it does not likely to be caused by the throw out bearing. The pressure plate usually has weighting to increase the pressure applied to the clutch disc as the RPMs are increased. If the clutch disc is a different thickness this could change the geometry and cause the effect. We changed weighting on our racing cart clutches to intentionally change slippage in the clutch. Same thing on funny cars and dragsters. These are exaggerated cases from the production car increase in force.

The question is what changed between the time the clutch worked properly and now.
 
It is a new clutch and pressure plate and throw out bearing. A clutch kit from Moss. Seems to work well, is nice and smooth.

When I compaired the new to the old the only difference I could see was the throwout bearing thickness. Old clutch and stuff long gone.

The change is a new clutch kit. All three parts.

Gesh, I hate the thought of pulling that engine again.
 
Jack - the problem ain't the Moss clutch kit you installed in your car!
 
I should not think so Tony.

It works well, next trick is......... beats me. Guess I will just run it and see what happens.

I am at a complete loss, have been through everything. It must be something real dumb. Strange no one else has seemingly ever had the problem.
 
Jack,

Did the clutch work properly at one point with the Moss clutch kit? You had multiple threads going and I got the flavor that the clutch worked well at one point and than did not after you had the oil leak problem. If it did work properly and you did not change the clutch disc and pressure plate, than they are not the problem. Just trying to stir you up, just trying to eliminate possibilities.
 
Since I changed the clutch and all, has not liked shifting at high RPM.

Pedel will go to the floor or almost so. At low RPM all is well.

However, I must say that it seems a bit better since I cleand the line and MC.

We will see.
 
OK - this is WAY out from left field but I wonder...
Is it possible that at high revs the fingers of the pressure plate are expanding (to give more driving force) too much, pushing the throw-out bearing too far to the rear so that when Jack pushes on the peddle he just doesn't have enough travel? I know that on the Mini there was a spring to pull the lever away from the pressure plate and an adjustable screw to keep it where it should stop. Is this even an option? Maybe Jack could mark where the lever is normally, rev up the engine and then without pushing the peddle see where the lever is. ???
Bill
 
& $300 for a rebuilt one at that!
 
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