Brake question

I recently did a lot of brake work to my 92 plymouth voyager (134k
miles). New cylinders in back, new shoes, and new pads up front. The
initial reason for the work was because I was almost down to the metal
on the fronts, and there was noise coming from the back right. A lot
of things were worn out so I changed the obvious parts. I ended up
bleeding the lines replacing the (green) brake fluid, which worked
well. The brakes still felt spongy, but were better than they had
been.

Yesterday, my brakes failed after about a week of working properly.
No fluid in the reservoir.

During the initial repair, while compressing the front right cylinder
back into the caliper, I heard what sounded like liquid spashing in
the area of the master cylinder. I assumed that I had overflowed the
reservoir, but when I checked, it wasn't full.

(as a tangent, I know you're supposed to open the bleeder valve when
pushing the cylinder back, but at that point, I was hoping to avoid a
bleed, and the manual didn't say to do it, and I had gotten away with
it half a dozen times before)

I was worried that I had broken a line or something else, but as I
said, everything worked properly and there were no obvious leaks in
the system after replacing the one cylinder in back. There was
acceptable pedal pressure and it worked fine for a week or so.

Obviously, there is a leak now. I'm assuming that the leak is not at
one of the wheels, becuase I would have only lost one circuit, right?
If that's true, that leaves the master cylinder, and possibly abs
parts I'm not very familiar with. The repair manual says to relieve
the pressure in the abs system by pressing the pedal 40 times or so
before bleeding, which I did.

Can anyone suggest a place to look for the leak? I'm sort of leaning
toward a bad master cylinder. Where would the brake fluid likely go
of this were the case?

Also, I initially tried the bleed with a hand pump, but got bad
results. I resorted to the two person method. This told me that the
hand pump worked, but the pump sucks so much air around the fitting
that it's hard to know if the air is coming from the lines or not.
This was after putting grease on the fittings. I'd like to use one of
those presurized systems that screw into the top of the master
cylinder. Are these safe with my abs system? I'm getting mixed
answers.

brian

 

You should be able to bleed that system like any other. How were the lines
in back? Sounds like you lost one. If there is a failure of the anti lock
system certain parts are covered for life.
Larry

 

ARe any parts of the ABS covered for life, like the pump?

 

If I lost one, the other circuit should have been ok though, right? I
lost both. I haven't had a chance to look at it yet. I thought I
would jack it up, put brake fluid in it, then pump the brakes until I
get a puddle. The lines in the back looked ok. I did bend some of
them slightly when putting the new cylinders on, but none were
leaking. It took a week to lose all the fluid. Maybe I did a front
one in while the calipers were off. They looked ok though. I hope
it's that easy. I still suspect the master cylinder.

brian

 

What can happen and what actually did happen to mine is fluid started to
blow out the top of the MC. Anyway when it occured I took it in and
everything was warrented. This at 150000 miles. The car was traded off with
over 200000 and the pump still working well.
Larry

 

So when the brake fluid was coming out the top of the master cylinder,
what was the fix? It sounds like you would need to replace the master
cylinder, but your post sounds like replacing the abs pump fixed it.
Also, if it is the abs pump, would they swap out the part if I brought
it to them since it's a lifetime warrantee or would I have to let a
dealer touch my car?

brian

 

GEt over it with the dealer. If you don't want to fine. It IS under
warranty. Not 100% but at least a large portion of it. I don't recall
exactly whatthey did (I think it was the ABS pump) but that vehicles frame
rusted out and it left my family last month for a Chevy Suburban. My
remaining mini van is a 99 T&C with a different system.
Larry