brake woes

[87manche]

it sure sounds mater cylinderish Wade.

that's what mine did shortly before the MC failed completely, on a downhill, on a trail.

 

[89eliminator]

mine got really crappy at WF and totally failed yesterday.

 

[87manche]

yeah, that's also what my clutch master did when it failed. Shot a stream of fluid about 6 inches straight up from the resovoir.

I had not problems running a reman on either of those though. Didi you look at the adjusting rod? Maybe yours is set deep, and it's pushing the seals into a nasty, not honed portion of the master.

 

[89eliminator]

yeah, that's also what my clutch master did when it failed. Shot a stream of fluid about 6 inches straight up from the resovoir.

I had not problems running a reman on either of those though. Didi you look at the adjusting rod? Maybe yours is set deep, and it's pushing the seals into a nasty, not honed portion of the master.

i didnt check the rod. however, even bench bleeding the MC results in a high stream shooting out. plus according to the directions for bench bleeding, the MC should get very firm which mine doesnt do.

 

[89eliminator]

finally i have brakes! good ones too.

the new MC did the trick.

 

[joe_peters]

finally i have brakes! good ones too.

the new MC did the trick.

Party time!arty:

Glad you got it fixed.

 

[kastein]

here is the deal...

for the past 8-10 months i have had sub-par brakes. the pedal will travel about 3/4 of the throw until there is enough pressure to slow the truck down.

new parts:
MC (3rd different one in the past time period). bench bled.
rear drums have been COMPLETELY rebuilt. new everything.
no air in the lines, guarantee.

when i hit the brakes, the small chamber in the MC shoots a stream about 1 foot high under full brake pressure (my 92 MJ does not do that). the cap seal cant contain that pressure so it is always leaking fluid.

here is the kicker, ever since i put on Rubi Express brake lines front and rear, the brakes have been crappy. i almost think they are expanding (causing the long brake pedal throw). but i dont see what could be causing the huge pressure in the MC.

so my questions are, is anyone else running the RE SS lines with good/bad feedback? i was thinking about putting the stock lines back on temporarily to see if that changes anything.

1. There shouldn't be ANY pressure in the MC reservoir, period.

2. If you are getting pressure in the MC (and what you describe IS pressure) then the MC is bad. As fluids are not compressible, and Pascal's Law is applicable in our dimension, that fountain of fluid is coming internally from the working part of MC.

3. Life lesson: most reman MCs are muy malo--very, very bad. Buy new, what the heck, the life you save may even be your own!

Really glad I just happened upon this thread. The MC in my MJ does exactly the same thing - except while bleeding the brakes, it shot so high it splashed all over the underside of the hood. I always figured it was from the front/rear reservoirs trying to balance out, guess I'm due for a 96 booster/MC swap.

If it aint one thing it's another...

EDIT: 89eliminator, any chance you still have a pic of your load adjusting valve around or know where I could find one? The linkage that connects mine to the diff is gone, the arm on the thing just flops around uselessly and I suspect it is causing some of my other wonky brake issues.