Quick brake question

[UltimateG]

I decided to bleed my brakes & replace the fluid today. My new jeep has 90k miles, and I don't know her history before I bought her. she's a '94 without abs. I've never done this before.

A few minutes ago, I siphoned all of the old fluid from the reservoir, and noticed that the bottom and sides of the thing is completely covered in some kind of soft gunk. I saw chunks coming down the hose when I was sucking out the old fluid.

Is this stuff okay? should I try to clean as much as I can out of it? Will I cause more damage by stirring things up? I was under the impression that any tiny impurity in the fluid could compromise it.

I'll be sitting here by the computer until y'all tell me enough to go out and finish the job properly.

Thanks
G

[KarlVP]

There aren't supposed to be any chunks in your brake fluid, it should be contamination free. After some use, it may get a little discolored (maybe similar to apple juice) but no chunks. It isn't the rubber seal that may have eaten away is it?

[KarlVP]

and bleeding brakes should be a two man job unless you have speed bleeders.

[UltimateG]

No, the rubber is okay. the stuff in there is more like grease or mud, not really lumpy, just a coating of gunk.

Decomposed brake fluid?

Installing speeder bleeders today, too.

[KarlVP]

Whatever it is, it's contamination, you don't want it in there.

How were your brakes before? Is there a reason you want a flush or just decided to dive into it?

[UltimateG]

How were your brakes before? Is there a reason you want a flush or just decided to dive into it?

I was bored.

And I don't know if it's ever been done here before. brakes weren't bad before.

[KarlVP]

DO NOT LET THE MASTER CYLINDER RUN DRY!!!

Get as much of the junk as you can out of there.

What I would do is hook up the speed bleeders, put a rubber hose into a can or bottle from each bleeder on caliper or drum, fill the resivoir with fresh fluid and pump the pedal two times, check the fluid, then pump two times.

Repeat this until you see fresh fluid coming out of the hoses.

Start with the back, and then do the front.

[Eagle]

Yes, get all that gunk out of the master cylinder. BEFORE you start bleeding ... so it doesn't get into the brake lines.

[RNMCGUIRE]

Mine was kinda like that when I bought it. I believe it's broken down fluid and dirt. I just took a medicine dropper and sucked all the fluid out of the master cylinder. Then I took a CLEAN rag and wiped out the master cylinder. Make sure you use a lint free / clean rag or you can make the problem worse. Then I filled with new fluid and bled them as normal until all fluid coming out was clear.

[anony91xj]

Yeah it's bad fluid. Just get out as much as you can, and fill the master cylinder with fresh DOT 3 fluid before bleeding the brakes.

I personally prefer to bleed brakes the old-fashioned way, with two people...I don't trust those speed-bleeders, but that's just me. Bleed until you see fresh fluid coming out...just bleed them in the right order. Start with the wheel farthest from the master cylinder (right rear) and work your way around, making the closest to the master (left front) the last wheel to be bled.

[UltimateG]

Wow, what a day. I'm still at it here.

I cleaned out all of the crap in the res, it was pretty easy actually. then began to bleed the brakes.

on the first wheel, my hose fell off, and the fluid sprayed all over the place. will it hurt anything?

I just installed a napa brand speed bleeder, and tightened it to 15 ft/lbs. Before I got it torqued in, it broke off in the backing plate.

shit. now how do I get this thing out?

[lawsoncl]

my hose fell off, and the fluid sprayed all over the place. will it hurt anything?

Get it off of any painted surfaces asap as brake fluid make a pretty good paint stripper. You sure Napa gave you the right threaded bleeders?

[KarlVP]

Brake fluid will hurt paint. The bleeder screw is a PITA, I have used vice grips before, easy outs, all sorts of things. We were doing a brake job on a celica once and we couldn't get the bleeder out. We had to get a new caliper.

[UltimateG]

this one's in the drum brake. the screw snapped off far enough down as to not leave any of it sticking out enough to grab with vice grips. Ez-out and screw extractors won't fit in either. Any other ideas?

I guess I need to take the whole mess apart. Probably just put in a new wheel cylinder. I've never done this before, and I don't have a manual. Any suggestions on how to do it? It looks like I just need to remove the shoes, and the wheel cylinder comes off of the backing plate with a couple of bolts. Is that all there is to it? Anyone know of a good how-to posted on the web?

Actually, the bottom half of the screw is in there pretty tight, I guess I'll just leave it for now, until I have more time to fix it?

[UltimateG]

.......

[KarlVP]

Yeah, a wheel cylinder is pretty inexpensive, I would just get a new one.

And Haynes / Chilton Manuals at your local parts store are about $20.00 I would pick one of those up because they have really good pics on how to's for rear drum brakes.

[Eagle]

I guess I need to take the whole mess apart. Probably just put in a new wheel cylinder. I've never done this before, and I don't have a manual. Any suggestions on how to do it? It looks like I just need to remove the shoes, and the wheel cylinder comes off of the backing plate with a couple of bolts. Is that all there is to it? Anyone know of a good how-to posted on the web?
That's all there is to it. Replacing the wheel cylinders on an older vehicle isn't a bad idea anyway. Be sure to put some anti-seize on the threads of the bleeder screws.

You do NOT need to remove the brake shoes if you just want to replace the wheel cylinder.

[Rick Anderson]

The seals and rubber hoses can deteriorate, leave small bits and gunk that can be in the system. It can be a dozen other things as well, like mentioned, what ever it is, flush it out.

A little gunk doesn't mean the seals or hoses or all coming apart.

Fresh brake fluid once a year or every couple of years goes a long way toward keeping your brakes working trouble free for many years.