Dumb*** master cylinder help needed...I replaced the really ****py master cyl in my 65 Merc the other day and today I started bleeding the brakes. All was going well until I suspected that the fluid was gettin blown out somewhere b/c I just could not put enough in to satisfy the prob...Bottom line, this is a manual system and I noticed that fluid was running out BEHIND the cylinder where it is bolted to the firewall. The cylinder with a replacement boot and 1 O ring type rubber seal which I installed. At this point I am ***uming that the fluid is leaking from the rear and blowing out of the the boot and seal. Is there something I may have installed incorrectly? I never replaced a manual cylinder before but this didn't seem much diffeent than a cylinder with power. Am I missing something and do you guys have any suggestions?? Do I need to take this thing off again and check the seal and boot? Oh, just one more thing, the studs that the other MC was attached to were rusted beyond repair and I pulled them out of the firewall and replaced them with new ones. Could it be that I did not seat the stud far enough into the wall before I bolted the cylinder back on? I just did not thing this thing would leak at all and will try suggestions at this point. Thanks
The kits come with instructions. Real men don't need instructions. May be you got the "cup" in backwards. It goes open end towards the fluid. It's gotta come back out. Amazing what brake fluid does to paint and carpet ain't it?
Instructions...you must be joking I throw that **** out haha...I figured I have to pull it and recheck everything including the studs. Just never had this happen before and really never thought it would leak out the back like this. Very happy the car is my project car so I don't have to worry about paint and carpet just yet. Thanks
It sounds like one of the rubber cups is in backwards. They go in the mc easier that way but don't work that way.
I think the concave (cup shaped) side of the rubber should face the inside of the cylinder where the fluid is contained.
boy what a flashback! i remember putting one in backwards in 1976 and swore it was correct and i can say crow really taste ****ty unless heated!
Unless im missing it you did not rebuild the master cylinder you just removed the old one and replaced it with a new one right? If that is the case you have a bad master cylinder I know what you are going to say its new, but let me tell ya I have seen plenty of bad parts come out of a clean box. Return it to where ever you bought it, buy a rebuild kit for your old one, rebuild the master per the instructions.
I replaced the rubber boot the same way the old one was in the car. I was wondering if the new m/c was bad but I will take the m/c off again tomorrow to check everything and try it again before getting another. I couldn't use the one that was on it as it was so rusted it was just trash and no rebuild would have brought that baby back.
So you put on a NEW master cylinder or a remanufactured one????? take it back.... The outer boot will not cause a leak. Something is amiss inside the master.
The rubber boot, nor the studs or mounting plate seals up ANY THING. If the fluid ain't contained inside the chamber it is wrong, bad, defective, ****, etc................
Thats what I was wondering....never saw fluid leak from the back like this and didn't even know it could......it is a reman by the way and thanks again.
Lemme guess-you got it at AutoZone-right? Like previously said,the rear boot is just a dust cover, the mc is leaking past the cups and is defective. Get your money back and buy a new one.
Yep...it was bad. I tool it off today and pushed the piston by hand with a tool and sure enough there was plenty of fluid inside the chamber which was bing pulled out when the piston returned to the extended position with the brake in the resting place. Something got screwed up in the reman so I just returned in and am waiting on the arrival of another one. Thanks all, we'll see what happens this weekend.
quick question: are you replacing the stock single reservoir MC with another single reservoir unit? now's the time to split your lines and install a dual reservoir MC. every old car i get has this done for safety's sake.
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