Does anyone else have this problem? Seems to be coming from the top. Did a couple launches today and hit the brakes kind of hard. Would the heat from the headers cause the fluid to expand and leak out? How about sealing the top with caulking around the outside edge?
Heat from the header can cause fluid to boil, but it takes *alot* of heat to do that there, even if the fluid is really old. Brake fluid is hydroscopic, so the water it can absorb will cause it's boiling point to lower when it gets old. Its usually not a problem unless you have a turbo there. As far as caulk, NO!!!!!!! There should be a gasket with the cover that seals it completly. Are you missing the gasket?
I agree with Slant, brake fluid will become saturated with moisture when exposed to atmosphere after awhile, and that increases the wet boiling temp to lower substantially. Like slant said, i don't think theres enough heat to expand it that rapidly. maybe the violent sloshing from the runs just spilled over, is the cap loose? gasket? don't put any sealant on the master cylinder, that would be a very bad idea. look into a new cap w/ gasket and slow down.. lol
As a matter of fact, I believe mine came from Auto Zone too. I massaged the hold down thingy, will see if it leaks tonight. Thanks for the info and replies Gentlemen. Jerry
What I have found on mine, is that small chunks of rust will be stuck to the gasket. Once the cap is taken off then put back on, it always leaks. I have cured mine by scraping the rust off the gasket with a knife blade. Then I take some 400 grit wet or dry sandpaper and sand the top of the master cylinder, where the gasket sits, being careful not to let anything fall inside. Then wipe everything dry and put the cap back on. It will not leak until I take the cap back off, then I have to do it all again.
I have the same problem. I replace mine with a rebuild and it still leaks. I have been told that the rebuild don't always seal well. I think cause the cover seems to wrap or something. I got mine from a local auto parts store. I cann't figure out why.
My master cylinder has a single bolt that holds down the cover. Is this the factory master cylinder? Don't think I have seen anyone elses car with this type hold down....sorry to hi-jack.... Don
