I'm sure this has been covered, but I'm not getting much out of the search function, which is running slow and sketchy.

Anyway, recently completed an axle swap on my 94 YJ. Dana 60s front and rear with high steer (tie rod behind the axle), 38.5 SX, 5.13s, Detroit, Lincoln, etc.

Anyway, everything seems to be working very well except ... I've got no brake pedal. Here's the rundown:

Stock YJ master cylinder and booster
Stock Ford dual piston front calipers (new)
Ford drums in the rear (completely rebuilt)
All new brake lines

Brake system has been completely bled. Still have very little pedal. I can pump it up and get a little pressure, but it evaporates quickly and I get very little brake engagement until just before the pedal bottoms out.

I'm assuming the stock Jeep components can't push enough fluid to activate the one-ton brakes properly. But, before replacing components I thought I'd check and see if there's anything obvious I'm missing.

FWIW, I ran a D30 and Ford 8.8 (four-wheel discs) previously with stock components and the brakes would put you through the windshield. Input appreciated.
Dion

Try the corvette MC and make sure the rod between the booster and MC is within 1/64. try to avoid the bellhanger jeep power setup (not enough throw) Navaho (Harold Off of Off Again) sells the complete setup for less than $500. Works great

Make sure the calipers are on the correct side

Originally posted by riksnacjnow
Try the corvette MC and make sure the rod between the booster and MC is within 1/64. try to avoid the bellhanger jeep power setup (not enough throw) Navaho (Harold Off of Off Again) sells the complete setup for less than $500. Works great

Hmm... your sayin the stock power booster w/ brake pedal doesn't have enough throw to get full use of anything bigger than a stock MC? (I'm running a Wagoneer I believe MC right now.)

I'm asking cause I am fighting my own brake issues.

if you have replaced everything like you said.. it will take awhile to bleed them.. i did this mine.. and it took forever.. im talkin alot longer than i would have thought.. and i too also believed i had issues.. but i just had to bleed them more..
your stock mc should be enough.. ive ran it... and others have also around me.. with no problems..

get the hydro-boost setup off of a 1ton truck. i swapped in hydro-boost and rear disc's at the same time and now it'll throw you over the hood if you don't have your seat belt on! they work better than any brake setup i have ever run.

Blatant, I have a 1995 YJ with one ton(60,14) running gear with four wheel disc and i swapped in a 1978 Mercury Grand Marquis MC. It bolts right up, completly dummy proof.

high5, you said use a hydroo boost from a one ton truck, do your remember what year and model you took it from? And did it bolt right up?

make sure your rear brakes are properly adjusted. this is a common problem on drum brake vehicles. this is how i adjust mine, and it works very well:

slide the drum off. if it comes off easily, with no drag from the pads, tighten the adjuster. i keep doing this until i feel drag both when putting the drum on AND when spinning it by hand. do this to both sides.

if it spins freely, but won't slide off, there is a ridge ont he lip that needs taken (ground) off. i just use my 4.5" grinder and knock it off, its mostly rust.

what it sounds like to me is all the fluid is going to the rear to push the shoes out, but they aren't contacting the drum. when you pump, the springs pull the shoes back in before you can get a full pump on it (springs are fast!). therefore, it takes a few pumps to get any kind of a solid feel. i prefer that the rear shoes noticeably drag the drums when turning by hand, but its still not difficult to get it turn...if they are too tight, they'll get hot and possibly glaze. you'll get the feel of it.

matt

'86 Ford E350 MC

$15 w/core

Stock brake set-up on my 1-tons, works great. Easy bolt-in and cheap. Search for details. It's been covered numerous times.

Maybe you should have had Pep Boys do that work for you. You obviously don't understand the concept of a brake system.

the concept of a brake system is to decellerate, stop, and/or hold a system that is in motion, or could be in motion if the brake was not there.

that is obvious.

now, understanding the concepts behind the functionality of each individual component in a brake system gets really close to brain surgery and rocket science.

ex. why is there a spring on the end of the parking brake equilizer bar? is it necessary? will the brakes work OK without the parking brake EQ bar? why are the shoes different? if the shoes were the same, would the brakes still work?

if you have some usefull information, please share it with us.

have you been to Pep Boys lately? if the guys in the shop are twice as sharp as the guys in the store...you are still in trouble.

matt

Originally posted by jeepnmatt

if you have some usefull information, please share it with us.


Ok, how about you shut up until you understand the problem with swapping in 1-ton brake hardware into a stock 1/4 ton system.

I'll put it in Pep Boy terms for you-

The big brakes need more fluid movement than the small cylinder provides. Go do your homework "jeepnPepBoy":flipoff2:

Oh wait!!!!!!!!!

I think I forgot one of these....






:flipoff2:

HeyBeerMan is still bitter because he doesn't fully understand the concept and implications of the Ackermann angle. That and I accidentally installed one of his freshly painted wheels backward about a year ago and he's never gotten over it.

Easy, Blake, I'll bring you a Silver Soda on the Highway 2 Hell night run this Saturday. Brakes? Who needs brakes as long as I can keep your junk in front of me to slow down on ...
d

HeyBeerMan is still bitter because he doesn't fully understand the concept and implications of the Ackermann angle. That and I accidentally installed one of his freshly painted wheels backward about a year ago and he's never gotten over it.

Easy, Blake, I'll bring you a Silver Soda on the Highway 2 Hell night run this Saturday. Brakes? Who needs brakes as long as I can keep your junk in front of me to slow down on ...
d

I'm not a fan of hydraboost...one push after engine stalls (I know...fuel injection) and you dont have much...almost like no power brakes at all or worse!
You have to change the whole system; brake booster, master cylinder, power steering pump and hoses....seems like alot of work to me.
I'm gonna try a 92-93 Chevrolet G30 van Vacuum assist with aluminum master cylinder...from what I was told it is a direct bolt in, including rod.
I agree with Bigdude, you definitly need to move more fluid faster than a 1/4 ton brake system can. What better to use than a 1 ton system?

Originally posted by 1tonyj
high5, you said use a hydroo boost from a one ton truck, do your remember what year and model you took it from? And did it bolt right up?

it came off of the same 87 crew cab 4x4 that i got my front dana60 from. no it did not just bolt up. i had to shorten the plunger and turn the mounting plate upside down. my 99 vortec 350 came from a 1ton dually that was equipped with hydro-boost so my ps pump was already set up for it. i have a couple of buddys who run it with a standard ps pump but they installed a "t" fitting in thier hose to allow for the leg to go to the booster.

Originally posted by 1BDYJ
I'm not a fan of hydraboost...one push after engine stalls (I know...fuel injection) and you dont have much...almost like no power brakes at all or worse!


with the eng off and after the shot in the res is used i can not tell a difference between the hydro-boost and a vacume operated booster system. if you lay in it it will stop. it has never been an issue for me off road though because like you say fuel injection doesn't stall on hills:D