Long story short, we ordered the "navajo" brake booster system from off-again yesterday & had it overnighted (don't have time to explain why right now)

Anyway, we got it today, the system comprises of a dual diaprham booster, m/c, bracket & adjustable rod.

Rick took the m/c off & bench bled & we mounted the booster to the firewall & attached the rod. However, when the m/c is mounted to the booster, pressing in the pedal doesn't push any fluid. It appears that either a: the pin in the end of the booster is too small for the m/c or b: the m/c is too bid for the pin. I'm going to try to post some links to some pix on my next post.

This is on an '85 CJ7.

Here is a picture of the "navajo" booster:
http://www.in2jeep.com/P9180105.JPG

here is a picture of the stock CJ booster:
http://www.in2jeep.com/P9180112.JPG

here is a picture of two m/c's the one on the left is a wagoneer m/c, the one on the right is the CJ m/c:
http://www.in2jeep.com/P9180108.JPG

here are two pictures of the end of the "navajo" m/c
http://www.in2jeep.com/P9180111.JPG
http://www.in2jeep.com/P9180110.JPG

When the pin (or rod or whatever) presses into the "navajo" m/c it isn't pushing against the washer type thinggy.
(sorry for the vagueness)

any thoughts? Has anyone used this setup? Should I just go ahead & use the CJ m/c for now - I am supposed to leave for the badlands tommorrow at noon.... and YES, I tried to call off-again about 10 times.

-Mel

Looks to me like the rod is just going up in the hole, it makes no sense that it would not be just a dish there for the rod to locate in. OR something is misssing in the MC. You could rig something up but I would use the stock CJ MC for now until you get an answer for the manufacturer. Weird. :(

Pictures aren't gunna do us any good. It is one of those cases where you have to be there to figure out. If you depress the pedal with the m/c off, how far does the push rod move? I would not be comparing the cj setup to the Navajo. Two different systems completely. You can pull the rod out of the booster and check the fit to the master. Only a seal holds it in, just pull hard on it, it will come out. Also, just because the m/c can be bench bled, does not mean the m/c is good. It may be passing fluid by the piston when it is connected to the system because there is pressure at the ports, unlike when it is bench bled. How was the bench bleeding done? It can be done wrong? If Navajo did indeed send you the correct matched pieces, and it was bled correctly, then I would have to say it is a bad master(after you verify the booster does have enough throw)

If the master cly came with the booster, I am going to pretend they know what they sent and that they work together..

Try bleeding the master cyl again.

An MC that is not thoroughly blead will push air instead of fluid and will act like nothing is happening.
When bench bleeding the new MC you should depress the piston/plunger then hold your fingers over the outlets when releasing it. This draws fluid into the cylinder.
Repeat until you get good squirt out of both outlets.

After mounting, try this sure fire MC bleeding technique from Van, the professional power brake man at VANCO ...

1. Get a helper to jump in the Jeep and work the petal.
2. Open the brake line fittings on the MC one half turn (both of them).
3. Have your helper push the brake pedal to the floor.
4. Tighten both brake lines and have the helper release the brake.
Repeat 2-4 until the fluid streams out of both ports without "sputtering".

This is quite similar to how brake caliper and slave cylinders are blead.
It completes bleeding all the air out of a new MC and also gets rid of air in the lines below the MC.

printing & taking to the garage.... thanks for the tips sofar.

BTW - Jaffer, it wont let me post over at ORC for some reason :confused:

-Mel

So Mel has it worked yet...














Damn I wish I had a hot little thing that fluncked Home Ec..
ouch hey stop that ,,, yes dear I love ALL of you, Ouch I said I was sorry, what do you want chocolate?

Well, the rod out of the booster doesn't stick out long enough to pump the "navajo" m/c - when Rick bench bled the "navajo" m/c he used a long screwdriver to get in far enough.

So, we hooked up the wagoneer m/c (which was brand new 2 days ago) - it is a 1.125" m/c vs. a 1" m/c for the CJ and the 1.25" navajo m/c

In the instructions it states "stock CJ m/c can be used with the booster, but is not recommended"

Well, we did Jaffers trick with the m/c as far as bleeding it goes on the vehicle & bled (the old fashioned way with me pumping the brakes & Rick cracking the bleeders) The pedal is spongy, and overall unsatisfactory.

Morale is down - its 11:30 PM - what is the NM time zone, wonder what time I can call them down there? I really wanted to be on the road to the Badlands by noon-1:00 tommorrow, seeing its a 7 hour trip.... not done with the laundry, need to pack... ugghh

Any other thoughts as to the culprit of our spongy pedal?

Well weld on an extension or go back to the other booster. also you could go manual. or temporaly nstall a shitload of washers and stoff in between othe two. so that thrust is transferd ... just an idea.

We bought a replacement stock booster, just in case.... it would be *passable* if we can get IT to work. We'll see what off-again have to say in the AM, before we resort to welding or washers...

Something is just plain not right with the system - and I'm not saying it is for sure something wrong with the Navajo... the waggy m/c is not THAT much of a difference, and that m/c was also used on J20 trucks that had dual diaphram boosters....

Also off-again used to sell JUST the boosters & not the m/c with it, & you'd use your stock CJ booster.

-Mel

Around here, when you say something has been "Navajo'd", it means that you just take and use any old piece of junk that you can get to work half assed.
It won't be the first time ...
I always thought he was using that trade name as a private joke. :rolleyes:

Originally posted by Melanie Frances West
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Any other thoughts as to the culprit of our spongy pedal?

Sounds like you still have air in the system and will need to bleed the brakes..

Hey, that looks like you have the wrong mc for your pb. Here is a pic of the 1/2 ton mc from my jimmy. see lots of push rod... the mc has a deep hole for the push rod to fit into.

http://www.classicgm.com/stuff/long.JPG


Now see the 3/4 ton I swapped in. looks like a normal length push rod to me...


http://www.classicgm.com/stuff/short.JPG


Both flanges on the PB are the same general size and depth, only diff is in the push rod length. me thinks you need call your supplier to see what up.