94, 2.5L 5 speed. Took it on the road for the first time today, after a year of working on it. I got to where I was going, about 8 miles away, and both of my front brakes were smoking. My guess is the pistons in the calipers are beginning to get seized, and so the first time I Stepped on the brakes they never fully released. My question is your opinions on what is causing this, or assuming mine is right, could I get the pistons working by moving the brakes back and forth manually with, say, a big @$$ screwdriver?
07-26-2009 06:01 AM
check pedal freeplay, lube caliper slides and pad guides, check hoses for kinks or bends, and maybe bleed brakes. thats what ide check.
no prying on caliper pistons. some are made of composite and break apart if you pry on them(dont ask how i know). leave the big ass screwdriver for other repairs
07-26-2009 12:05 PM
Sounds like your pistions aren`t releasing completely, you may get lucky and be able to saave them but I wouldn`t count on it.
Could be air, but more than likely its rust on the piston arm causing it not deploy fully.
Ususally when they go, they`re done,
07-26-2009 03:12 PM
Well, I have a slightly larger problem now. I was troubleshooting today with my father and the help of a mechanic, stepped on the brake...and POP goes the brake line.
07-26-2009 04:30 PM
I agree with what everyone else is leaning towards. If it is not the caliper slides I would replace both calipers. As far as the brake line goes you can replace just the bad part with a new line and union fittings- 3/16" line. If there is any more rust though I would make a whole new line. I redid all of my lines for about $20, if you do have to make a connection in your line use a union fitting not a compression fitting.
07-26-2009 05:57 PM
Yeah, I found a compression fitting on it that the previous owner put on there. I would like to replace the entire line...but I Can't seem to disconnect either end of it. (This line goes to the left rear brake drum, not one of the front). The line connects at the back to a thicker line that goes to the brake drum itself. Where this connection is, is a metal plate. The connecting nuts, on either side of the plate, are rusted on...and enough force to break the nuts loose would also break the plate. I can probably mount it elsewhere, but I also can't get the other side of it disconnected.
07-26-2009 06:03 PM
You could zip tie it to the mount. If you cant get the line disconnected you could just replace the part it goes to (ex: wheel cylinder) and replace all of the bad line.
07-26-2009 08:39 PM
Yeah, ziptie is probably the way I'll go. There's only a few spots that are rusted, the rest of the line is pretty good....but I might as well just replace the whole thing so one of the other spots doesn't go, and replace the worst of the other brake lines with any excess if I get a large amount.
07-26-2009 09:20 PM
One more question- Do you think I should spend the extra money on lines that already have the fittings, or get the bulk lines and connectors, and get the tool to put the connectors on myself?
07-26-2009 09:30 PM
its raining so i cant check right now but i think mine has a fittings on driver's side inner front frame rail and it looks stock.
you can make your own but make sure you double flair lines, or you can get 2 sections of line and just install coupler between two.
ide use two rather than one large due to ease of install and they are as safe as one single piece.
07-26-2009 11:08 PM
I bought like a 60" sections that had nuts on it and a couple of 12" sections to get extra hardware. The nuts that come on line fit your stock jeep hoses. Get a decent double flare tool and make sure to follow the directions, if the flare is not good it will leak.
07-27-2009 10:02 AM
I didn't read all the replies in this thread, so maybe you've already fixed this brake issue... however, if not - IF the brake is holding on, try letting the car sit for 30 minutes. If you can roll the car easily after the 30 minutes (i.e. the brake has "let go"), then I would say you should take a look at replacing the rubber brake hose to that wheel. When those hoses get older, they can expand under brake pressure - but take their time contracting, causing the brake to be "on" until the hose completely contracts. If the above doesn't apply, then I would think you are looking to replace the caliper - which is pretty inexpensive and a relatively easy fix.
07-27-2009 01:39 PM
Hmm, that's an interesting possibility. Local mechanic seemed puzzled by the possibility of both calipers doing the same thing...but the hoses seem more likely to both go. His other suggestion was that perhaps it is the master cylinder-and the brakes did back off overnight, before I blew the brake line, but now I can't really test that. I'll look into the hoses...and have yet one more question. Does anyone have a suggestion for a reliable double flair tool? I've seen prices from $22 to $350+, so I'm just curious if anyone knows one or another to be reliable and effective.
07-27-2009 01:58 PM
I got my flaring tool from Home Depot, if I remember correctly.
I would fix the brake line, then test out the brake hose. Quite frankly, the brake hose and the caliper are basically the same price - around $ 25 each - so either fix will cost you the same. You just want to make sure you fix the right thing first ;)
07-27-2009 02:40 PM
Seriously? Where could I get a caliper for $25? I haven't seen under $95, although I've basically just looked at new ones on jcwhitney and quadratec.
Edit: Scratch that, partstrain has them for that price.
07-27-2009 03:54 PM
Okay, I feel kind of pathetic...but I seriously can't get the brake line disconnected. I'm still fairly much a novice at this sort of this- And no wrench seems to fit the nuts on the end of the line, and using a crescant wrench, whatever, I simply can't get them to move. From the master cylinder, a line goes into some little splitter dohickey, from which every other line comes out of. The line I need to replace comes out of the bottom left of this splitter...and I can't get the nut to move, no matter how hard I try. Any advice on getting these off? I don't want to strip the nut, and I've been coming close to that with trying to get them off.
07-27-2009 04:05 PM
If you haven't done so already, spray that fitting with PB Blast, a very good rust-loosener. After you spray it, tap it several times with the end of a screwdriver to gently coax it in there further. Use a vice-grip on the fitting, getting the vice as tight as you can. Be sure to hold the 'splitter dohickey' (fantastic) steady while you try to get the fitting loose with the vice-grip. If that doesn't work, you may need to consider cutting the brake line directly in front of the fitting and then using a six-point socket and wrench, after working some more PB Blast in there...
07-27-2009 04:07 PM
Sounds good to me, as soon as I get a chance to get another can of PB I'll get on it..last can ran out a few days ago :P
And no wrench seems to fit the nuts on the end of the line
I am not sure, but they may be flare nuts and that could be the trouble. When my mechanically inclined friend and I worked on my brakes he had told me to get a flare nut wrench. I did so without question, so I have no experience with how a normal wrench or crescent wrench might work on those. If the kit that you get has flare nuts, it might be worth the investment to get a flare nut wrench so you do not damage the new nuts.
Maybe I am completely wrong and yours are just stuck. Figured it wouldn't hurt to mention it.
07-30-2009 05:12 PM
So, it doesn't really seem to matter what I do- I really, genuinly, can't get them off. I replaced the body mount bolts, and THEY were easier to get out than any of the brake line flare nuts. Flare nut wrench of the right size just starts to round the nut. I put PB blaster in a plastic bag, and taped it up-the nut and threads were immersed in PB blaster for the entire night. Did that change a thing? Nope. 3/8's drive ratchet with a 1/2 inch socket does...nothing. Admittedly, I Can't get much leverage on it. But damn, these things are genuinly stuck on. Anyone got a miracle answer? :P
07-30-2009 09:44 PM
Sometimes on a caliper casting, the bleeder screw can be loosened by hammering gently around the area where the fitting is in the casting. Use a ball peen to make small dents etc.
Not sure if this will work for the line fittings without seeing it.
07-30-2009 10:34 PM
My apologies, let me clear that up: What I'm trying to get free is a brake line at the "splitter dohickey", as I so aptly called it. the master cylinder runs two lines into this, and then the other brake lines run out of it, to the wheels.
Yeah, that. The line on the bottom right in that picture is the one that I can't get off- Although, trying to get others off just to see I couldn't make them move either >_o
07-30-2009 11:45 PM
and now it totally striped out? can u get it out with channel locks or vice grips?
07-31-2009 12:49 AM
I coulda have saved you a sh*t ton of work.... Take you caliper off completely make sure its drained, grab an air chuck and place it where the line goes in, grab a 2x4 and place between the piston and caliper and apply air, KEEP FINGERS CLEAR! it will easily sheer fingers off after that try to push it back in and than if it slides easier you might have had it in half cocked or there is a ridge.... if it doesnt help or already been suggested here just ignore lol
07-31-2009 01:04 AM
No, it's not completely rounded...the one in the back that connects to the soft hose for the left rear wheel cylinder is rounded a little, but can still be grabbed. The one in front on that splitter can be grabbed pretty easily..but applying more force than I have WILL round it.
07-31-2009 01:12 AM
cut the lines and put a socket on it
07-31-2009 04:06 PM
i will refer you to the pirate 4x4's brake bible after you figure this out. its really intresting. and welcome to the constant jeep wrangler brake battle! oh yes, have you checked you prop valve? if its giving to much fluid to the front brakes they will smoke.