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Clutch Master Cylinder Leaking..

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peterh

Freshman Member
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OK So after succesfully bleeding the clutch my hunt for the leak in my system was interrupted by a small Hurricane called Frances which caused the car to be buried under other 'stuff' in the garage. Now that I have dug it out again I found the leak and it doesn't look good.

When I press the clutch pedal in fluid comes out of the master cylinder around the dust cover...leaks into the foot well and then ultimately leaks down onto the floor.

Any suggestions or advice is welcome. I have the workshop manual and if I had to guess I say that maybe one of the washers or seals has gone bad. Is it a difficult job to take off the cluster master cylinder?
 
I might suggest that you check the condition of the master cylinder's bore. If it's chewed up or has pitting from rust and corrosion or moisture building up in old brake fluid it may be worth your while to either replace the unit with a new one ( it's very difficult to return a cylinder bore to the necessary smoothness by honing) or take it to a competent machinist and have a sleeve machined and fitted to the cylinder - I had the Brake and clutch master cylinders and the slave cylinder for my Sprite done locally and had stainless steel sleeves made - This cost more than replacement units but the upside is I think they'll last from now on with little danger of pitting and corrosion - Just a rebuild kit occasionally.
 
Repair kit ordered...should be here for the weekend...hopefully before the next Hurricane.

(On the basis that there is no such thing as a dumb question)

When I undo the fluid inlet pipe how do I stop the fluid from running out of the reservoir?
 
Peter get a rag and a small jar and slowly loosen the line from the reservoir where it attaches to the master cylinder. Catch the fluid that drains from the line in the jar. The reservior has a small inner reservior that feeds the brakes so there will still be fluid in the reservior even after the line is drained. There is a clevis inside the car and 2 bolts on the firewall that hold the master in the car. Just install the new seals and cups in the right direction like the book shows and reinstall and bleed the master and you will be fine. Skip
 
/ubbthreads/images/graemlins/savewave.gif
Skip, the small inner section of the dual fluid reservoir feeds the clutch not the brakes.-FWIW---Keoke /ubbthreads/images/graemlins/yesnod.gif
 
/ubbthreads/images/graemlins/savewave.gif Peterh, Another Method:

Before you undo the the fluid pipe get a large Battery type syringe,they are used to put water in the battery cells, and remove the fluid from the reservior. they are available at most good auto parts stores. use the fluid to lubicate the new seals but do not put it back in the system.-FWIW---Keoke /ubbthreads/images/graemlins/thumbsup.gif
 
Keoke's method is a good one. Here's another: I went to Southern States Co-op (agricultural supplies) and purchased a huge syringe. It holds several ounces of fluid. Put the open (needle) end in the master cylinder and extract the fluid. Works like a charm, and it can be reused.

The syringe cost about 3 bucks, I think. Worked for me!
 
I thought I'd get a jump start on the weekend this evening and take out the clutch master cylinder. I undid the clutch pedal and removed the pipes all the while managing to spill only the required amount of fluid.

However the securing bolts seem to be stuck fast and look well attached. I am under the dash turning anti-clockwise on the nuts but can't seem to get any movement.

I considered applying some WD-40 but the idea of mixing that with the brake fluid might not be one of my best ideas.

Any thoughts on loosening these bolts?
 
Peterh, try loosening the bolts from the engine compartment side.---Keoke
 
Skip said this was simple. Next time I am going to get him to come and undo those bolts!!!! (-:

Finally got them off and the cylinder removed although the lower bolt was hard work due to just being awkward to get any leverage on it. The nuts are still attached on the dash side...are they supposed to be or should those come off?
 
/ubbthreads/images/graemlins/savewave.gif OH MY GOSH NO!! Peterh, /ubbthreads/images/graemlins/nonono.gif They are not pose to come off.---Keoke /ubbthreads/images/graemlins/laugh.gif
 
Well thanks Keoke..that goes a long way to explaining why I was having so much trouble trying to get those off. /ubbthreads/images/graemlins/crazy.gif

Still waiting for my rebuild kit but sucessfully dis-assembled the cylinder. Looks in good shape but the end seal was no where to be found. I'll let you know how the rebuild goes.
 
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