Brake problems

So yesterday I dropped my Jeep to have new ball joints installed (no time between now and NAC Fest to do it myself). I get a call from the garage today telling me that they will need at least another day to fix the brakes and the u-joint. Of course, I was a little shocked by this, since the brakes were fine on the drive over. I could see needing a new u-joint, I haven't checked those yet, but the brakes were as good as you could expect them to be on a Jeep.

I told them to leave everything else the way it was, and took it to the allignment shop for my appointment tomorrow. It's like I don't have rear brakes at all now. From what the garage says, there is no fluid in the MC, and there is no sign of a leak. I was underneath it last night fixing the tailpipe, and I didn't see any wet areas.

Any ideas as to where I should be looking? Could the MC somehow purge the fluid out?

Yes. If the master cylinder seal at the aft end of the piston fails, the brake fluid can be sucked out of the MC and back into the vacuum booster.

However, I've never seen that type of failure happen instantly. You should have been seeing a slow loss of fluid for quite some time (you DO check your brake fluid every couple of weeks or so, don'cha?).

Pull the rear drums. If you don't see evidence of dripping or seeping fluid back there, fill up the MC, bleed the brakes, and drive it. Check the MC level once or twice a day and see if you're losing fluid, or if an unscrupulous shop just siphoned out all your joy juice hoping to sell you and expensive brake job.

just for ball joints? if it had brake fluid when you dropped it off it probably didnt leak... look at your front brake lines to see if they removed the calipers instead of hanging them while it was apart... maybe they broke a brake line and didnt say? sounds a lil shady to me... does this shop have a good rep? fluid generally wont leak without leaving a mess somewhere... heres a thought. maybe when they compressed the caliper piston to reinstall it they pushed the fluid back and overflowed the master cyl... i know ive done it.. and when the pedal was first pumped it filled the lines again maybe got low enough to get air in the line for the rear??? hope you get it straightened out for nacfest... good luck!

"joy juice" can be used as brake fluid?

The last time I checked the fluid was before my last wheeling trip, maybe 3 weeks ago. The Jeep did sit for a week while I was at the Outer Banks, but there wasn't much more underneath it than the usual 3" spot of tranny fluid under the crossmember. I doubt there was a leak before I took it to the shop.

As far as the place being reputable, I've been taking my junk there for at least a couple years, mostly for stuff I don't really WANT to do, and I've never had a problem like this. Sure, they've tried to "save" me money by "rebuilding" my front hubs in the past, but I never thought something like this could happen.

I think I'm going to go ahead and install the YJ front lines, and maybe swap in my 44 (all new brakes parts) before NACFest so that I can be sure it isn't a leaky line. Which part of the MC is for the front, and which is for the back? Maybe that would help me figure this out. Anyone have a link to an online FSM for an 88 XJ?

The large reservoir is the front, the small reservoir is the rear.

There was an on-line '88 FSM being circulated here a few weeks ago. Dunno if it's still available or if there was a copyright issue that got it removed. Does anyone have a link?

Also ... look at the hard line from the MC to the rear axle. I have an '88 and that line popped on mine about 2 years ago. I cut out a couple of feet that looked like the rusted portion, laboriously double-flared the cut ends and spliced in a new section, then got a friend to push the pedal when I bled the brakes. Got a nice firm peddle, I was just tightening down the bleeder screw when Erich stepped on it one more time just to see how firm the peddle felt.

SPLAT! Lost another 3 feet of hard line. The second time I replaced it from the firewall to the rear hose - none of the short patch stuff.

Well, it looks like the driver's side hard line on the rear axle is to blame. How hard is it to make a line that fits? I assume I'll need a flaring tool, but will I need a tool to bend the line with as well? If it's possible, I'm thinking about installing the hard line from the 44 so I don't have to swap axles (it should fit shouldn't it) and then replacing ALL of the hard lines with stainless after summer is over and I'm not trying to wheel every weekend. I'd at least like to get through NACFest and the Bradford, Pa Jeep Jamboree before I take some time off to build again.

I replaced all of the lines to the rear from the prop valve last week. It's not too difficult, but be prepared to spend some time tinkering with the bends to get them right.

I'd suggest getting a tubing bender, it makes life a lot easier.

What I do heartily recommend is getting a GOOD flare tool. Somebody here a couple of years ago suggested the pliers style from J.C. Whitney, and it works GREAT. I've never been able to get a good flare out of a bar & yoke style, and it's pretty easy with the pliers tool.

You can find hard lines already flared and with the ends at most parts stores.
Wayne