Danger Strange Growth - Master Cylinder

Caution

I'm doing my thing cleaning up the engine compartment on my 72 and I figure that the rusted Master Cylinder lid needed to be cleaned up. So, I flipped the bail and HOLY CRAP the top pops off and this black thing jumps out. It made me jump back (primal fear of black things jumping at you I guess)

Man, I have never seen this before. It appears that over the past 39 years the MC gasket has converted brake fluid into mass and expanded about a third in all dimensions.

Check it out.


The replacement is from NAPA P/N 675-1206 (say's Ford) and seems to fit perfectly.

I may need therapy.

 

Wow, mine doesn't look to far off from you old one. mine sticks out about an 1/8 inch from the lid all the way around. Guess I need to replace mine as well. thanks for the part #.

 

when the rubber seal swells like that it means that the brake system is contaminated with an oil base product.

 

Nice, I can't wait until the wheel cylinders parts start to swell. I cleaned out all remaining fluid in the MC and refilled. Guess a brake system clean out/rebuild is in order. I'll put it on the list.

 

I've had one do that before, someone once told me its ok to use brake fluid in the power steering reservoir when in a pinch,,, that wasn't a problem,,, but DON'T DO IT THE OTHER WAY ROUND!! brakes do not like power steering fluid! oops

 

had the same thing happen when a guy at work( i supervise minimum custody inmates) filled the master cyl with oil. what a moron . i had to repace everything but the hard lines.

 

the wife added tranny fluid to hers years ago.....had to replace all the rubber (lines calipers cylinders) lesson learned.