Mushy Brakes.

[Mars]

Hey guys, just got my new coupe, and i have a small problem with the brakes.

They are firm at first, and then do the mush in the occasionally (like they need to be bled)

Theres no leaks in the fluid, and the fluid is full.
Someone told me that i need a new master cylinder (called it something like internal cylindar leak).

Before i got drop 50 bucks on a new master cylinder,

a) is this something i can fix?
b) is this even the problem?

thanks

[B16KILLA]

My car is starting to do the same thing , The manual says to pressure bleed/flush the brakes but I dont want to pay someone to do it. My question is can you just bleed all the fluid out, fill it up and then, bleed it again to get the air out ?

[Mars]

Its not that hard to bleed brakes. I wouldnt flush all of the fluid out unless it old.

[B16KILLA]

Mine is old I've been meaning to change it but no time-----:slap:

[Legend_master]

Its not that hard to bleed brakes. I wouldnt flush all of the fluid out unless it old.


my friend had this problem in his 4g and it turned out to be a bad brake booster. We replaced it and the problem was fixed. As for bleeding the brakes, that is pretty simple as long as you have a friend to help you pump the brakes.

[Jareds 89 LX-i]

If there's air in the system, the pedal will be consistantly spongy no matter what. The master cylinder however can be tempermental and sometimes feel fine and other times mushy. This was just the case with mine when the master cylinder went bad, cool nights it was fine but during the day when it was roasting it would sink to the floor. Easiest way to tell if master cylinder is leaking internally, hold the pedal down, if it's firm at first then slowly starts to sink down then the master cylinder is bad and needs to be replaced

[86-accord-lxi]

If the master cylinder has ever been run out of fluid, It could have sucked in air. You could try bench bleeding the master cylinder, But if your going to be removing it, Might as well get a new one. Especially if it's the original.
If you hold down on the pedal ,Then start the car, and the pedal doesn't go down a little, The booster may be bad. Also, make sure your rear wheel cylinder aren't leaking first.

[Mars]

Easiest way to tell if master cylinder is leaking internally, hold the pedal down, if it's firm at first then slowly starts to sink down then the master cylinder is bad and needs to be replaced

exactly what mine is doing.

[Blkblurr]

Guys, it sounds like the seals in the master cylinder are worn and passing brake fluid past them. You will not see a leak because it's internal. You need to rebuild the master cylinder. On older mustangs I've had you could buy a rebuild kit for it. I honed the bore of the master cylinder as well.

[Mars]

I called the parts store, and they said they have rebuild kits for about 30 bucks, and the whole cylinder is 55. Does the rebuild do the trick or should i get the whole thing?

[Cant Stop]

your choice save a few bucks or just r/r the part.
just clean the fluid out of your booster as it tends to drain in there when the back seal goes out.

[TheWatcher]

Considering how old the car is ... if your gonna replace the master cylinder, you might as well replace the brake lines too.

Peace.

[Legend_master]

Considering how old the car is ... if your gonna replace the master cylinder, you might as well replace the brake lines too.
Peace.


:werd: i second that

[Mars]

Might could use this as an excuse to get some steel braided lines =)

[Blkblurr]

My lines are nearly as good as new with the exception of being dirty. Do many of you have lines that rust out?

[Mars]

rust out?
mine are rubber man.

[Legend_master]

My lines are nearly as good as new with the exception of being dirty. Do many of you have lines that rust out?


Mine were kinda cracked with age on my car and my old legend also. THey jsut dry up and wear out.

[FyreDaug]

I think he meant rusting out as in the actual steel lines before it gets to the rubber... never seen it happen

[Cant Stop]

ya northern cars can rust out especially in states where there is salt on the roads for the snow i had a car that the steel fuel line rusted out and the front steel lines rusted too. so ya it can happen usually alot of the underside is rotted out as well when this happens , my car was a 72 ford montego mx station wagon with 90,000 miles and 400 pounds of steel rusted away .

[FyreDaug]

400lbs? LOL

[Mars]

meh thats like.... 2% of the body weight on a 72 ford station wagon XD