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TR2/3/3A My theory about my clutch hydraulic problems

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Lukens

Lukens

Jedi Warrior
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I've mentioned in previous posts that I could not find the source repeating "soft pedal" and air in my clutch hydraulics. Here's what I think has been the problem:
I found the wavy spring washer in the MC broken, with a section completely missing. This would allow juice to be sometimes be pushed back into the reservoir instead of to the slave. When this happens I would rapidly pump the pedal which would be a source for air getting back into the cylinder.
I also see that my plunger did not have the rear seal on it (some diagrams show it with and some without?). I'm thinking this would allow the plunger to "****" a little in the bore and not seal properly, thus increasing the chance of drawing air.
I had a MC repair kit on hand from Moss, but I'm disappointed to see that the spring washer is not included... bummer. I'll have to get one before I can prove my theory.

Russ
 
FWIW, Girling deleted the rear seal and said to leave the slot empty.
GIRLING MC REBUILD - LEAVE OUT O-RING.jpg

https://i258.photobucket.com/albums...es/Girling Master Cylinder 2 raw.jpg~original
 
Lukens said:
...I had a MC repair kit on hand from Moss, but I'm disappointed to see that the spring washer is not included... bummer. I'll have to get one before I can prove my theory.
Click to expand...

Ah, automated censors. Difficult to think of a better word - maybe 'cant' or 'pitch'?

I'm pretty sure I can find that washer in my garage - PM me with your address if you want it.
 
Yes leave that rear seal off the plunger because if it does not have a perfect fit the piston will drag and the actual clutch will slip on the disc. I think the piece was only felt anyways perhaps to keep dust out of bore. I replaced one once with an O ring and caused problems.
 
Randall, sp53, I'll leave the rear seal out.
FWIW when I applied air to the cylinder and pushed the plunger without the rear seal, it would leak if pushed off center. With the seal. couldn't get a leak.
 
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It sounds like maybe the bore has been honed a few times too many if you are seeing enough slop to affect the seal. Might want to opt for a new MC instead of messing with worn out parts.
 
CJD said:
It sounds like maybe the bore has been honed a few times too many if you are seeing enough slop to affect the seal. Might want to opt for a new MC instead of messing with worn out parts.
Click to expand...
I'd agree accept I installed the MC new 2 years ago.
 
Lukens said:
I'd agree accept I installed the MC new 2 years ago.
Click to expand...

So the spring didn't even last 2 years...bummer! That is one of the reasons I prefer to re-use original parts when it is at all possible. It seems odd that the piston would be loose enough in the bore to affect the seal...possibly more quality issues with that MC?
 
And the bore may be oversize (or piston undersize) just from sloppy manufacturing. The original pistons fit the original bores quite snugly, so much so that they can be hard to get apart. With only a few thousandths clearance, the piston cannot tip enough to change the seal.
 
TR3driver said:
And the bore may be oversize (or piston undersize) just from sloppy manufacturing. The original pistons fit the original bores quite snugly, so much so that they can be hard to get apart. With only a few thousandths clearance, the piston cannot tip enough to change the seal.
Click to expand...

Understood. What's the negative to using the rear seal/
 
I think Randall mentioned that earlier...more drag can cause the piston to lag or stick when returning to the full out position. It's sort of a "Catch 22" situation. If the main seal leaks, the rear seal will prevent the fluid from escaping...but if the main seal does leak, the MC is already broke and needs repair.
 
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