Power Brakes Question ?

[AMC86Kid]

My power brake fluid is leaking

and i was wondering if anyone knew an easy way to fix it 

it is leaking where the Master cylinder connects to the Power Brake Booster

on the bottom part of the master cylinder 

do i have to replace the master cylinder or 

is there something that i can just put on in between there 

to get the leak to stop?

 

i will also post a pic for you guys to see

[AMC86Kid]

here are the pics

 

the whole thing 

 

under it 

 

close up 

[AMC86Kid]

it would be great to get my brakes working like new 

i have put new pads on the front and new shoes in the back

also i bleed the lines and put new fluid in it 

thats when i noticed the leak

 

the Master cylinder looks like it just needs a light cleaning and it will look ok 

but the Power Brake Booster defiantly needs more then just a light cleaning 

its seen better days :(

 

any advice will help guys thanks for reading 

[Eagle]

The seal inside the master cylinder is leaking. You'll have to replace the master cylinder.

[Marine1Texas]

yep master cylinder need replaced. Do it before that fluid starts giving you problem!

[AMC86Kid]

ok so i just unbolt the old M.C. 

and bolt in a new M.C.

then add new fluid and thats it 

 

can anyone tell me the proper way to replace it 

and what to do to get the brakes working correctly after I'm done replacing the part?

 

also will a master cylinder repair kit work or do i just have to buy a new M.C.

http://www.rockauto.com/en/moreinfo.php?pk=907419&cc=1181393&jsn=453

[schardein]

Buy a new master cylinder.  You will need to bench bleed it, don't skip this (google or you tube bench bleeding a m/c).  Then swap it out, top off, then you will need to bleed the brakes.  If you haven't done that yet, you may find your bleeder screws are rusted shut.  Start treating them now with a rust penetrant like pb blaster or the like.  Treat them daily several days before doing the work.  If one snaps off you will have to replace that caliper or wheel cylinder.  

 

Now would be the time to swap to a dual diaphragm booster from a 96 XJ for better power brakes.  Your power brake booster could be damaged from that m/c leak (or maybe not).  If you do the swap, the booster must use the matching 96 master cylinder.  However this requires some brake line work which may be over your head based on your questions.

[AMC86Kid]

ok i will take it apart tomorrow

and see if the brake booster can be reused

or if it must be replaced

 

i will also try to post a pic of what it looks like taken apart 

hopefully a auto parts store will have it in stock 

[Eagle]

ok i will take it apart tomorrow

and see if the brake booster can be reused

or if it must be replaced

 

i will also try to post a pic of what it looks like taken apart 

hopefully a auto parts store will have it in stock 

 

https://www.napaonline.com/napa/en/search/?text=Brake%20master%20cylinder&isApplication=true&isInterchange=true&referer=herofitmentForm-newveh#

[big66440]

I agree with schardein OP, the 95-96 XJ dual diaphragm brake booster upgrade is leaps and bounds much better than the original set up even in "brand new condition". There's tons of info on the upgrade from many forums since it is very popular, but it will require a bit more work and maybe tools.

[AMC86Kid]

yes i see that the dual diaphragm brake booster is better because it pushes out more pressure 

but I'm just going to keep it simple and put a new regular one for now 

i also got a new flare wrench set 

it the SAE one i thought that since the vehicle is made in the USA it would not have any metric size nuts on it 

[Eagle]

it the SAE one i thought that since the vehicle is made in the USA it would not have any metric size nuts on it 

 

For the brake lines, the SAE set is the one you need. But elsewhere ... the XJ and MJ came out during the period when AMC was merged with Renault, which is a French company. Also, that was right at the time when the U.S. automobile industry was on a push toward metrication. You're going to find that most of the nuts and bolkts on the engine are SAE, but most of the nuts and bolts on the body and chassis are metric. For regular wrenches and sockets, you're going to need both metric and SAE.

[Mattman6]

I agree with schardein OP, the 95-96 XJ dual diaphragm brake booster upgrade is leaps and bounds much better than the original set up even in "brand new condition". There's tons of info on the upgrade from many forums since it is very popular, but it will require a bit more work and maybe tools.

After researching I would agree. I have one sitting waiting to be installed on my MJ.

[AMC86Kid]

ok good i will let you guys know how the brake job goes and hopefully take a pic and show you guys