NO WONDER THE PARKING BREAK WAS STICKING! (Pics)

[todds112]

The only hic-up I had on my 1000 mile journey home with the "new" truck was the parking brake froze on for a bit. I just quit using it and placed in on "the list" of things I wanted to address eventually.

Yesterday I started to hear a "clank" in the rear like two metal plates hitting each other. Sounded like it was coming from the parking brake area. I put my new 125 jets in today and went to go for a test drive and felt that familiar drag on the driveline and heard the clank. Could not get it to release this time. Boy did I NOT want to tear into that today (10 degrees out).

Special thanks to Russell McIntire for the great write up on this. Russ if you want to add something. On the 712, I had to loosen all 4 body mounts on the central tube support (between axles) in addition to the one above the trailer hitch. The acorn nut above there was STILL a total PITA (If I ever get my hands on THAT engineer ).

When I finally got to the brake assembly I was shocked at what I found:









There was a thick black powder all over everything. I'm assuming it was from the pads. They look like they have plenty of lining but the lining is cracking in several places. I couldn't believe how rusted everything was! The draw straps, the lever, everything. The pin for the straps was fused to them. Took a BFH and a puch to knock it out! YUCK!!!

I've guessing I'm pretty screwed and will have to replace EVERYTHING in there. Any suggestions on what to clean up the housing with. The braking surfaces actually look pretty good, no gouges or anything. I'm thinking a brass wire wheel to clean up the back of the hitch assembly (but not the actual braking surface).

Can't really tell if the seal from the rear locker is shot or not. Doesn't seem to be any oil in there, just rust and crud. I'll look at it better after I clean it up.

Any advice appreciated.

Thanks again, Russ!

[todds112]

PS, I probably poisoned myself with asbestos too, becuase I didn't wear a mask like Russ suggested. Don't do that at home kids.

[PinzEOD]

Could you get in there with a small siphon type bead blaster? Maybe pack some rags around the 'greasy' parts to keep the abrasive out. I've never had mine apart so I'm not familiar at all with what I'm seeing in your pics. A Dremel can get into some pretty tight places...or even an air grinder with a small abrasive bit.

[milesdzyn]

Looks to me like its only surface rust. Clean it, paint it, put it back together.
As long as the linings still good you'll be fine, you could get a relining kit from one of the dealers if you aren't sure.

Oh and don't paint the contact surfaces.

Miles

[lindenengineering]

Todd
Obviously the the truck has been submerged in that area at some time in its past.

The unit is only for parking or emergency stops so you don't have to go mad. You can clean most of it with aerosol brake cleaner from Napa (I am sure you know where that place is on the main street in Jackson)
The pivots/links/faces you can emery cloth up 'n polish and lube the pins with a sachet of brake grease from Napa or you can go across the road to that clapboard hardware store opposite and buy a pot of anti-seize lube.

The tail cone seal looks like its about to start leaking and will probably be the original neoprene seal that has gone hard with heat produced by having the brake partially engaged!

If it was in my shop we would be recommending a tear down to the diff main case, check the bearing and replace the seal with a Viton material seal that resists higher heat values.Bung on a new O ring for good measure and rebuild it.

Don't over do the course adjustment on the operating arm and it MUST NOT go over centre. The cable should be twisted several turns after the jaw end is set to engage with the arm and the external spring hooked up.
Test the truck for free engagement of the brake then drive. If you overdo it the brake will drag all over again, overheat, burn up the discs and the seal. then you will have to do it all over again!
Best of Luck
Dennis

[todds112]

Yeah it appears water got in there and couldn't get out. I just ordered all new internal stuff from SAV. The whole steel plate kit was only $185. I am getting new linings too. I Didn't like the looks of those cracks. Since they spin at the same rate as the drive train when not engaged, I can see them self-destructing (at the most in convenient time.)

Should I used that shelac based sealant or something else when I close up the cases?

I decided I'm going to hold off on the tail cone tear down for now. Probably re-visit that this summer when it's warmer. Now that I know how to get in there, it won't be that bad (especially if it's not 10 degrees out).

Dennis, I have to wait for Sunrise Home Center to refil their metric nut/bolt section. I bought them all out already!

[75pinz]

Todd, methinks you might be throwing money away here. It is a parking brake. Clean it up and drive it man! 185 bucks will buy you a lot of gas. I would check that bearing and replace the seal if it needs it since you are in there. sure it spins fast but if you only put it on when parking it then it won't be spinning too fast then. I know you are used to a new Jeep and I can tell that you are one anal guy. I bet that thing is a lot cleaner than it was when you picked it up...

[M Wehrman]

There are a lot of trucks out there with cracks in the ft rotors from hard use. I would not have any fears of the rotor coming apart. Usually a rotor condition like that would cause pulsation in ft brakes,but your e-brake would not be used at speed so I would go along with the other guys and clean-lube-reassemble and DRIVE!
Mark

[lindenengineering]

Hey Todd
No pint (sorry beer on the brain) point in daubing the faces in sealant, the housing is open to the air if you look through the side holes you can see the protrusion into the chamber.

I forgot to mention that putting a few twists on the handrake cable forces the umbrella handle & shaft up in the cab to adopt a twist which makes pull application easier.

I am surprised that hardware store even had metric bolts, it reminded me of a typical farm store in Nebraska where everything is "Merican".
Dennis
ps What does that force up there give you blokes to drive? Not those Crown Vics I hope! If so Lord have mercy upon you lot.

[todds112]

The office:



It's tough but someone has to do it.

Anal? Is it that obvious? I actually had a Jeep strand me in the middle of no where because the parking brake froze up too. Because of the terrain around here I will use the heck outta the parking brake. Just want to have confidence it will work and be reliable.

[lindenengineering]

Todd
Well that's a start!
Maybe you can convince the "powers to be" that the next time you want a service vehicle/come office replacement they should consider a G Wagon. Its now merican yu know (Daimler Chrysler)
Stay safe
Dennis

[todds112]

Ok, if you guys think I can revive it, I'll give it a try and see what happens.

Guess I'll get my wire brush fired up! Maybe I'll spray those pivot arms with some kind of rust converter too while I'm at it.

Brake grease...check.

Thanks guys.

[Jim LaGuardia]

Use Anti-sieze to lube all the parts, replacement of the wedge plates is a good thing. $185 is cheep insurance and sure to work for years to come

[todds112]

Todd
Well that's a start!
Maybe you can convince the "powers to be" that the next time you want a service vehicle/come office replacement they should consider a G Wagon. Its now merican yu know (Daimler Chrysler)
Stay safe
Dennis

Ha Ha, the Sheriff saw the Pinz and he thinks I am nuts. I told him that's OK, just give me a call next they have a SAR (search and rescue) and need to haul people and equipment to some back corner of the county nothing else will make it to.

You'ld be amazed at the placed I've taken that Tahoe.

[milesdzyn]

As far as anti seize goes try Dow Corning compound 111. Its great for a multitude of uses. Good stuff.

Moisture barrier
Anti seize
Valve guide lube
Brake cylinder assembley grease
Bimetalic corrosion inhibiter
Dielectric grease

Miles