LaredoBucket

Hello All,

Recently I noticed my brakes feel a bit spongy. I can hear a hissing sound as I apply pressure to my brake pedal. This morning I noticed a puddle of fluid under the drivers side firewall. Could this mean Master Cylinder needs replacing? I can't tell where it may be leaking from. I also noticed the rubber seal under the master cylinder cap wasn't fastened properly. I'm gonna see if this fixes my problem. haha!

XJ-kee

hijacking this thread so I get updates about it. I have something similar on my 2000. Hit my brakes and it almost sounds like a puff of air from near the pedal. No brake fluid leaks, everything is perfectly full, nothing seems wrong other than having to brake a little sooner. Hopefully someone has something !

JPXJMOAB

you sound like you need to bleed the master cylinder

JPXJMOAB

fix the cap as that is a pressurized system, then see from there what you've got for leaks .. Brake clean everything and have a buddy sit in it and pump the brakes while you look for leaks. It's probably a line fitting leaking.

XJ-kee

This is actually on the list for this weekend! Just bought a bleeder kit so I'm having the girlfriend helping me out. good to know I'm on the right track with it

cruiser54

I'm betting the leaking master cylinder has taken it's toll on the innards of the booster.

Both are probably in need of replacement.

diskman

My 1992 MC was leaking and it ate the booster guts and the paint on the firewall.

I pulled a 2002 GC booster and MC and did the conversion.

Its like night and day. My XJ now has nice firm brakes that will stop on a dime and give you change back.

I suggest finding a local salvage yard and doing the booster/MC upgrade. You will also need the MC brake lines that run to the prop-valve. They will need to be bent to line up.

WELL worth it. I think I spent under $50 for the entire project. Look into it.

cruiser54

You are correct.

LaredoBucket

It was the MC Rubber Seal. I seated it properly and cleaned up the surrounding areas with brake cleaner. DUH!!! No More Leaks!!

JPXJMOAB

awesome glad to hear it!

Bustedback

That rubber seal in the master cylinder cap is actually a seal and a water separator. It's a good idea to remove the rubber and clean it off a few times a year, especially in high humidity areas.