This just sort of belongs in here, but I'm not sure where else to ask, and I know you all know the most about brake nonsense. Here's the story: my master cylinder went bad, so I replaced it. Now, maybe two weeks since replacing it, my brakes are crap again. I know for a fact that my driver's side rear caliper locked up, for different reasons (I'm assuming...I don't know what the MC would have to do with one caliper). The pedal pressure is now basically nonexistant, but the car still stops fine, just at the very end of the pedal travel. I check the MC reservoir, and whoop, no fluid! So it's completely leaked out somewhere. I'm gonna go over it tomorrow, but my real question is: is my MC ok, though I've used with apparently NO fluid at all, or have the seals been blown out now?

 

You should examine your lines and calipers very throughly. Check for even slight leaks. You may have a caliper in poor shape, or a bad line. Have you replaced that rear caliper yet? if not try that first, that may be alot of your problem

and

learn how to use caps lock noob.

and

give me my impact wrench and socket back!!!

and

that is all

-s

 

it could be a leak from you MC BB check up under the dash.

This happened to my civic, it was a slow leak

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by slammed_93_hatch &raquo;</TD></TR><TR><TD CLASS="quote">it could be a leak from you MC BB check up under the dash.

This happened to my civic, it was a slow leak </TD></TR></TABLE>

Good point as well.

 

another thing to try as you look for leaks is to have someone in the car pushing on the brakes. That will pressurize the brake system, and a leak will be a lot more obvious...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by sander &raquo;</TD></TR><TR><TD CLASS="quote">

Good point as well.

</TD></TR></TABLE>

It took me FOREVER to figure out where the hell I was losing brake fluid in my old Prelude. I finally jacked it up, started it, and went crazy on the brake pedal to see if it would drip somewhere. Next thing I know, my car is engulfed in SMOKE and still no brake fluid.

My lesson, M/C's can lose fluid into the BB, which can fill up and send brake fluid into your intake via the vacuum line. I learned a lot about brakes that day.

Let us know what you find out.. I hate brakes too. Soft pedals own me.

-Chris

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Chris F &raquo;</TD></TR><TR><TD CLASS="quote">My lesson, M/C's can lose fluid into the BB, which can fill up and send brake fluid into your intake via the vacuum line.</TD></TR></TABLE>


Well, I wound up getting stuck in the woods on a broken-down dirtbike, so the examination won't happen until tomorrow, but the car is just sitting for now.

And Sander, you want that stuff back tomorrow? Call my place, Comcast is out of commission for all of Baltimore, so I have no internet at home.

 

Did you bench bleed the MC before installation?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by RineRacing &raquo;</TD></TR><TR><TD CLASS="quote">Did you bench bleed the MC before installation?</TD></TR></TABLE>

I sure didn't. Didn't even know this was required. What's involved?

I did manage to get everything apart today, and that driver's side rear caliper was pretty darn screwed up. The piston had extended, and somehow fused to the cylinder it normally resides in, and to the backing plate of the pad it was touching. I had to hammer the **** out of it just to get it off the car, then hammer it some more to get everything apart. The handy-dandy brake piston squishing cube did jack squat, so I might as well use it for a paperweight.

After all this though, I looked everything over very carefully, all lines, calipers, MC, and BB, and could not find ANY leaks. I'm stumped. Tomorrow I'll put new fluid in, see if I can spot any leaks, and go from there.

Meanwhile, does anyone know if I should/shouldn't use that MC again, since it's been driven on with no fluid?

 

It is just a roll of the dice on the m/c. If it hasn't been driven too long dry & nothing got in there to damage the o-rings, then it should be fine. The question is how much is your time worth. I would go out & get a re-manned m/c & rear caliper. Make sure to bench bleed the m/c. Otherwise it is almost impossible to get all the air out.

 

Caliper is already taken care of. Again, I'm not sure what bench bleeding is. Care to explain?

And is there a way to test the MC, or just sort of guess by pedal feel once it's in the car?

 

you have hoses connected to the output that go back into the fluid res. fluid is in the res. push the rod in. air is pushed out of 'lines' into res. when no more bubbles, you are good to go. take whole assembly to car. install. remove connections right before hooking up the hard lines.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by sscguy &raquo;</TD></TR><TR><TD CLASS="quote">

I sure didn't. Didn't even know this was required. What's involved?

I?</TD></TR></TABLE>

pretty much ya.

you bleed the MC befor you put it into the car. simply fill up the resivior with fuild push the rod in then plug the brake line wholes and let the piston out repeat the steps untill little to no air comes out.( its helpfull to have 2 or 3 people and a vice.)

once the air is out or mosly out you plug the holes and then attach the lines, now its impossible to keep all the air out of the MC but its certiantly alot easier the less is there.

once its set up bleed the brake lines that go into the MC just like you would a caliper, then move to the calipers.

again some people don't do this but I have had the best of luck doing things this way, but its a alot of stuff that isn't exactly fun to do

 

I can show you sometime this weekend, just call me later on.

-s

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by sander &raquo;</TD></TR><TR><TD CLASS="quote">I can show you sometime this weekend, just call me later on.

-s</TD></TR></TABLE>

I'm calling you this afternoon, I need this **** taken care of.

 

Problem apparently solved. Seems like it was something with that crapped out caliper and/or the MC not being bled by me properly when I installed it.

 

 

*Sigh* So...it turns out the problems not quite solved. The fittings going into the MC are leaking. I'm not sure if the holes in the MC are stripped, if the fittings are messed up, or what, but any significant pedal pressure makes fluid squirt out there. Does anyone know if using teflon tape on those fittings is bad?

 

the thread doesnt seal the fluid. its the flared part of the line, make sure you have all dirt cleaned off the fittings in the mc, and also make sure they are not bent.

-s