International Full Size Jeep Association
Home Forums Reader's Rigs Tech Library Trail Stories FSJ-List
International Full Size Jeep Association  

Go Back   International Full Size Jeep Association > Tire Kickin' > General FSJ Tech

Reply
 
Thread Tools Search this Thread Display Modes
  #1  
Old 07-24-2013, 02:16 PM
Dr. Marneaus's Avatar
Dr. Marneaus Dr. Marneaus is offline
FSJ Maniac
 
Join Date: Jun 16, 2010
Location: Reno, NV
Posts: 2,886
A little more brake help please

So the brake battle wages on.

I am on my 3rd master cylinder. I bench bled it and its hard as a rock. Good to go. I am on my 2nd J20 booster. SEEMS to be fine. holds vacuum, the pedal releases kind of slow but it's not too bad. Gonna assume it's okay.

I adjusted the rear drums until they have what feels like even drag on both sides. just a lil bit of drag. You push the wheel with your hand and it stops maybe after 1/4 turn. Without the engine running, pedal feels pretty decent, but still travels a bit far it seems. With engine running, i can push the pedal all the way to the floor, but it is harder than before.

If i take a test drive down the road, I can stop the truck from like 25mph without having the put the pedal to the floor. however if I push harder when stopped, I can get the pedal to the floor. If i stomp, the pedal will go to the floor, the truck slows a bit, and then the rear brakes will BOTH lock up. Previously I had only 1 rear brake lock up on my. Now they both lock evenly and leave even skid marks. I assume this means they are both adjusted pretty close to each other. The braking appears to be acting normal, but it doesnt stop all that well, and the pedal moving so far seems wrong.

what's my next step? The pedal just moves too dang far and isn't super super hard. One line on my prop valve is seeping, but literally to the point where it doesn't drip or anything, it just has a drop hanging from it. I'll address this, but that shouldn't cause the issues I'm having. Somebody said either get the rear drums turned or do new drums.shoes just to make sure stuff isn't out of spec.

I'm so close I can taste it!
__________________
Quote:
Originally Posted by FSJunkie
Dr. Marneaus is now officially my idol.

The Mag - The Wag

The Beast Build Thread:Marns '73 Wagoneer Thread
1973 Wagoneer - 1987 360 w/ factory 4bbl - TH400 - D20 - D30/D44
Reply With Quote
  #2  
Old 07-24-2013, 02:39 PM
Kenall's Avatar
Kenall Kenall is offline
Moderator
 
Join Date: Apr 15, 2000
Location: Sacramento, CA.
Posts: 2,886
vice clamps.











with vice clamps you can shut off the corners of the wag to isolate where the 'sponge' is.

clamp off all hoses. test for firmness.
if firm, booster and MC are good.

release front clamps, clamp off the hose above the rear axle.
test pedal firmness. if pedal stiff, problem could still be in rear.

clamp off front R or L hose (in turn), repeat test.
__________________
Ken's:
1966 Super Wagoneer
5.7L 2BBl. Th700R4. NP-208. Opens. 3.31s. 4core. 4Discs. PS,PB,AC,CC,Cassette.
(Soon to be TBI)
"If it aint leaking, it's empty!"
Reply With Quote
  #3  
Old 07-24-2013, 03:18 PM
joe joe is offline
 
Join Date: Apr 28, 2000
Location: PNWet, USA
Posts: 22,378
Any weeps, drips or squirts from any of the fluid carrying parts of the brake system is NOT ok or good'nuf. Fix the obvious issues, re-bleed the entire system before you go looking for other issues you may or may not have. Your Wag is what an early 70's era? When you did the drum brakes you did buy/install a new hardware kit and adjusters right or you relying on 40 year old repeatedly cooked/cooled hardware?
Drum turning is never a bad idea if you have enough metal left to keep them in spec. Having the new shoes arched to newly turned drums is worth the little extra expense if you can find a shop that still does that. Not likely though since the lawyers took over the world. I've never arched shoes on a car at home but have somewhat arched shoes on the rear drum of bikes. It's involved but possible.
Start with fixing any leaks, weeps, then bleed, then do a few mild (low speed) normal backing out your driveway reversing drills to get the final self adjusting function stuff a chance to work. If fixing fluid leaks, manually adjusting shoes, correctly re-bleeding and the backing drill doesn't work. Do a chalk test on the shoes and see if the entire shoe is mating with the drum or just parts of the shoe.
Just thinking out loud here...when you installed the new shoes you didn't mix up the leading shoes with the trailing shoes did ya?
__________________
joe
"Don't mind me. I'm just here for the alibi"
Reply With Quote
  #4  
Old 07-24-2013, 03:33 PM
Dr. Marneaus's Avatar
Dr. Marneaus Dr. Marneaus is offline
FSJ Maniac
 
Join Date: Jun 16, 2010
Location: Reno, NV
Posts: 2,886
nothing on the rear axle is new except the wheel cylinders and the lines.

The drums, shoes, and hardware were all on this axle when I bought it to do the swap.

Everything worked fine when i still had drums on the front. The truck stopped like normal. The issues arose when i did the disc swap, now nothing is right. Every single part of my brake system is from a 77. Literally including the pedal, all the way to each wheel.

Can anybody confirm that the lines heading from the MC to the prop valve for the front are supposed to be 3/16? and also that the lines from the prop valve to each wheel are supposed to be 3/16?

I haven't really thought about line sbeing the issue, but from whaty I remember before, everything to the front was 3/16, and everything to the back is 1/4"
__________________
Quote:
Originally Posted by FSJunkie
Dr. Marneaus is now officially my idol.

The Mag - The Wag

The Beast Build Thread:Marns '73 Wagoneer Thread
1973 Wagoneer - 1987 360 w/ factory 4bbl - TH400 - D20 - D30/D44
Reply With Quote
  #5  
Old 07-24-2013, 03:35 PM
Dr. Marneaus's Avatar
Dr. Marneaus Dr. Marneaus is offline
FSJ Maniac
 
Join Date: Jun 16, 2010
Location: Reno, NV
Posts: 2,886
Quote:
Originally Posted by Kenall
vice clamps


with vice clamps you can shut off the corners of the wag to isolate where the 'sponge' is.

clamp off all hoses. test for firmness.
if firm, booster and MC are good.

release front clamps, clamp off the hose above the rear axle.
test pedal firmness. if pedal stiff, problem could still be in rear.

clamp off front R or L hose (in turn), repeat test.

good idea. I need more vice grips tho.
__________________
Quote:
Originally Posted by FSJunkie
Dr. Marneaus is now officially my idol.

The Mag - The Wag

The Beast Build Thread:Marns '73 Wagoneer Thread
1973 Wagoneer - 1987 360 w/ factory 4bbl - TH400 - D20 - D30/D44
Reply With Quote
  #6  
Old 07-24-2013, 03:38 PM
addicted's Avatar
addicted addicted is offline
Big Meanie
 
Join Date: Dec 11, 2004
Location: Byron, MI
Posts: 4,876
Quote:
Originally Posted by Dr. Marneaus
nothing on the rear axle is new except the wheel cylinders and the lines.

The drums, shoes, and hardware were all on this axle when I bought it to do the swap.

Everything worked fine when i still had drums on the front. The truck stopped like normal. The issues arose when i did the disc swap, now nothing is right. Every single part of my brake system is from a 77. Literally including the pedal, all the way to each wheel.

Can anybody confirm that the lines heading from the MC to the prop valve for the front are supposed to be 3/16? and also that the lines from the prop valve to each wheel are supposed to be 3/16?

I haven't really thought about line sbeing the issue, but from whaty I remember before, everything to the front was 3/16, and everything to the back is 1/4"

The front lines are all 3/16". The rear is 1/4" until it splits at the axle from the rubber hose.

Did you use everything for the brake pedal; bracket, mount, push rod everything? It seems as though you're not getting a full push.

Oh and vice grips can crush your rubber lines and ruin them from the inside.
__________________
Quote:
Originally posted by Ristow
i bet it was Simon....
he's such big meanie that way...
please don't tell him i said that....
Reply With Quote
  #7  
Old 07-24-2013, 03:43 PM
Rich88's Avatar
Rich88 Rich88 is offline
FSJ Maniac
 
Join Date: Nov 20, 2008
Location: Wilds of Ellington, CT
Posts: 4,182
Quote:
Originally Posted by Dr. Marneaus
So the brake battle wages on.

I am on my 3rd master cylinder. I bench bled it and its hard as a rock. Good to go. I am on my 2nd J20 booster. SEEMS to be fine. holds vacuum, the pedal releases kind of slow but it's not too bad. Gonna assume it's okay.

I adjusted the rear drums until they have what feels like even drag on both sides. just a lil bit of drag. You push the wheel with your hand and it stops maybe after 1/4 turn. Without the engine running, pedal feels pretty decent, but still travels a bit far it seems. With engine running, i can push the pedal all the way to the floor, but it is harder than before.

If i take a test drive down the road, I can stop the truck from like 25mph without having the put the pedal to the floor. however if I push harder when stopped, I can get the pedal to the floor. If i stomp, the pedal will go to the floor, the truck slows a bit, and then the rear brakes will BOTH lock up. Previously I had only 1 rear brake lock up on my. Now they both lock evenly and leave even skid marks. I assume this means they are both adjusted pretty close to each other. The braking appears to be acting normal, but it doesnt stop all that well, and the pedal moving so far seems wrong.

what's my next step? The pedal just moves too dang far and isn't super super hard. One line on my prop valve is seeping, but literally to the point where it doesn't drip or anything, it just has a drop hanging from it. I'll address this, but that shouldn't cause the issues I'm having. Somebody said either get the rear drums turned or do new drums.shoes just to make sure stuff isn't out of spec.

I'm so close I can taste it!

I'm very anal about getting drums or rotors turned every time I replace pads or shoes. Further, no (reputable) shop will replace pads or shoes without turning or insisting on new metal. And not just as an upsell, but for good reasons. 1) safety, 2) liability, and 3) pads/shoes need to seat, and the newly turned hi-friction surface will do just that. Having said that, still doesn't address the soft pedal. Only air, or very soft hoses can do that. Further, you mentioned locking up only the rears. Whatever the problem, if you can't lock up all 4 then you're not done yet. Its a traumatic event, but I always do it on my first test drive after a brake job.

Anyway, I suspect the proportioning valve.
__________________
Jeepasaurus (Wagonus Grandi quadropedus)
88 GW 360-.030 over/2150/727/229/Posi, e-pump, AC (broke), tow package, Monroe Air Shocks, TFI, CTO-Free, AIR-free, oil & tranny coolers, dried knuckle blood all over, GM 350 TBI in a box, waiting...
"You're an FSJ'r when the parts guys memorize your name, phone & credit card#."

Last edited by Rich88 : 07-24-2013 at 03:50 PM.
Reply With Quote
  #8  
Old 07-24-2013, 03:59 PM
joe joe is offline
 
Join Date: Apr 28, 2000
Location: PNWet, USA
Posts: 22,378
I've never had /felt the need to do a disc brake swap so no idea what size lines are required for your car or the swap brake parts used but fluid system/line integrity "IS" required with juice brakes. FIX THE LEAKS FIRST, then diagnose from from there. Be it body or mechanical stuff and I'm bleeding out from an artery I'm for lets stop the bleeding before we discuss $$$ voodoo surgery.
__________________
joe
"Don't mind me. I'm just here for the alibi"
Reply With Quote
  #9  
Old 07-24-2013, 04:13 PM
Dr. Marneaus's Avatar
Dr. Marneaus Dr. Marneaus is offline
FSJ Maniac
 
Join Date: Jun 16, 2010
Location: Reno, NV
Posts: 2,886
Quote:
Originally Posted by Rich88
I'm very anal about getting drums or rotors turned every time I replace pads or shoes. Further, no (reputable) shop will replace pads or shoes without turning or insisting on new metal. And not just as an upsell, but for good reasons. 1) safety, 2) liability, and 3) pads/shoes need to seat, and the newly turned hi-friction surface will do just that. Having said that, still doesn't address the soft pedal. Only air, or very soft hoses can do that. Further, you mentioned locking up only the rears. Whatever the problem, if you can't lock up all 4 then you're not done yet. Its a traumatic event, but I always do it on my first test drive after a brake job.

Anyway, I suspect the proportioning valve.

prop valve is a brand new unit from BJ's. I coughed up the gazillion dollars for one when i have what was supposedly a perfectly good used unit on my hands.

I'm going to put a test light on it tonight and see if the valve is stuck in either direction.
__________________
Quote:
Originally Posted by FSJunkie
Dr. Marneaus is now officially my idol.

The Mag - The Wag

The Beast Build Thread:Marns '73 Wagoneer Thread
1973 Wagoneer - 1987 360 w/ factory 4bbl - TH400 - D20 - D30/D44
Reply With Quote
  #10  
Old 07-24-2013, 04:16 PM
Dr. Marneaus's Avatar
Dr. Marneaus Dr. Marneaus is offline
FSJ Maniac
 
Join Date: Jun 16, 2010
Location: Reno, NV
Posts: 2,886
Quote:
Originally Posted by addicted
The front lines are all 3/16". The rear is 1/4" until it splits at the axle from the rubber hose.

Did you use everything for the brake pedal; bracket, mount, push rod everything? It seems as though you're not getting a full push.

Oh and vice grips can crush your rubber lines and ruin them from the inside.

Literally every part is 1977 era.

The bracket under the dash, the pedal, the booster bracket, the booster, the master, the lines (home made but made to 77 specs), the prop valve, the rear lines, the wheel cylinders, the calipers, the pads/shoes, the drums and the rotors.

Lol. Yes. Every dang single part of the system is 1974+

I believe I'm getting a full push, because the rears are locking up solid. There is some resistance before i hit the floor with the pedal, but i can push through it if that makes sense? Other than that, i dont feel like i should have to push the pedal 3/4 of the way before it causes the truck to slow down significantly. That doesnt bode well for any emergency situations, even if that last 1/4 of the travel is hard.
__________________
Quote:
Originally Posted by FSJunkie
Dr. Marneaus is now officially my idol.

The Mag - The Wag

The Beast Build Thread:Marns '73 Wagoneer Thread
1973 Wagoneer - 1987 360 w/ factory 4bbl - TH400 - D20 - D30/D44
Reply With Quote
  #11  
Old 07-24-2013, 05:37 PM
Banchee's Avatar
Banchee Banchee is offline
232 I6
 
Join Date: Mar 20, 2009
Location: So. California
Posts: 163
Quote:
Originally Posted by joe
fluid system/line integrity "IS" required with juice brakes. FIX THE LEAKS FIRST, then diagnose from from there.

I have seen you mention this twice here but no response from the OP. Seems like one would fix the known problems then move forward. If there is fluid leaking out, then there is also air and probably moisture leaking in to the braking system to some degree.

I saw that the new master cyl. was bench bleed, but didn't see mension of bleeding the complete system. (But you can't do that until the system is leak free!) I was also wondering if there is more than one hole in the brake pedal lever for the push rod to attach to. Some brake pedal levers have 2 holes up at the push rod. I have seen (and repaired) a couple of cars that someone had attached the push rod to the wrong hole in the lever and they were not getting full travel or full pressure out of the brake system.

Other things to check, flex lines could be colapsed inside if they are old. Rust inside steel lines. Is the engine pulling enough vacuum, where are you picking up vacuum from for the booster?
__________________
91 XJ Cherokee Limited
99 Dodge Ram V10 4X4 (This thing will pull a house, but won't pass a gas station)
2010 Grand Cherokee (Hemi)
2014 Dodge Avenger SRT6 Blacktop
Reply With Quote
  #12  
Old 07-24-2013, 05:54 PM
Dr. Marneaus's Avatar
Dr. Marneaus Dr. Marneaus is offline
FSJ Maniac
 
Join Date: Jun 16, 2010
Location: Reno, NV
Posts: 2,886
I will try to fix the weeping line. This involves cutting the line, and splicing in with a union a new line that will hopefully fit. Apparently my flaring skills are not exactly top notch, as is evidenced by the fact that this one fitting is weeping.

Yes. I bled the whole system. Also, this is not the first time i've ever bled brakes so I would like to htink I'm not simply doing it wrong, but stranger things have happened. Also I have had several different people as my helper. I am working on my 4th quarts of fluid through this system trying to get everything to work. Gravity bled, vacuum bled, two person bled.

All brake lines except for the front two going from the prop valve to the soft lines are new. Rear soft line is new. front soft lines are new.

Engine is pulling plenty of vacuum, normally runs around 19" when its warm and idling. I'm pulling vacuum from the front of the carb. the big port. I'm not having a hard time getting the pedal down, as if there was no power. The pedal goes too far, too easy.

Maybe thats how a double diaphragm booster is supposed to feel, but i somehow doubt it.

the brake pedal only has 1 rod coming of of it where the booster rod attaches.
__________________
Quote:
Originally Posted by FSJunkie
Dr. Marneaus is now officially my idol.

The Mag - The Wag

The Beast Build Thread:Marns '73 Wagoneer Thread
1973 Wagoneer - 1987 360 w/ factory 4bbl - TH400 - D20 - D30/D44

Last edited by Dr. Marneaus : 07-24-2013 at 05:57 PM.
Reply With Quote
  #13  
Old 07-24-2013, 06:00 PM
Tripwire's Avatar
Tripwire Tripwire is offline
hey,does anyone here know how to.......
 
Join Date: Jul 30, 2000
Location: WA State
Posts: 4,413
As suggested previously (since you have new soft lines) are the drums oversize? ( turned to many times) or the shoes backwards ? - IIRC but not certain the larger/longer one faces towards the front.....

Do you have acess to another similar rig? perhaps some DSPO put in a substitute "close enough" brake pedal assy and thats your issue..... grasping at straws here folks...
__________________
Abort? Retry? Ignore? >

86 GrandWag. Howell fuel Injected 360. MSD Ignition + Dizzy. 727/229 swap BJ's 2" Lift and 31's

88 Wrangler 4.2, Howell TBI and MSD - Borla Headers w/ Cat-back + winch and 31's AND a M416 trailer (-:

Last edited by Tripwire : 07-24-2013 at 06:03 PM.
Reply With Quote
  #14  
Old 07-24-2013, 07:18 PM
serehill's Avatar
serehill serehill is offline
Gone,Never Forgotten.
 
Join Date: Nov 22, 2009
Location: Mesquite Texas
Posts: 8,622
Have to agree Andrew

The leak can cause spongyness if it leaks it's getting air. Flairing is a tough trick for me too. Good luck. Make sure the line is square & the flair edges are symetric.

Good luck Bud.
__________________

80 Cherokee
360 ci 727 with
Comp cams 270 h
NP208
Edlebrock performer intake
Holley 4180
Msd total multi spark.
4" rusty's springs
Member, FSJ Prissy Restoration Association

If you can't make it better why waste your time. No use repeating the orignal mistakes. I'm to old to push it that's why.

Last edited by serehill : 07-24-2013 at 07:23 PM.
Reply With Quote
  #15  
Old 07-24-2013, 08:03 PM
shosandjeep's Avatar
shosandjeep shosandjeep is offline
232 I6
 
Join Date: Apr 27, 2012
Location: Dexter, Maine
Posts: 26
Doc, when you adjusted the rear brakes, did you tighten the star wheel until you couldn't turn the wheel and tire by hand, then back off the star wheel 10 clicks? Old school method, but it seats the shoes. If you only adjusted until you felt drag, you didn't get them tight enough, especially with unturned drums. Just a thought.
Reply With Quote
  #16  
Old 07-24-2013, 08:45 PM
Kenall's Avatar
Kenall Kenall is offline
Moderator
 
Join Date: Apr 15, 2000
Location: Sacramento, CA.
Posts: 2,886
Quote:
Originally Posted by addicted
Oh and vice grips can crush your rubber lines and ruin them from the inside.

oh yea, if you're trying throttle a guy stealing your bacon cheeseburger, but not when your wishing to stop fluid flow.
__________________
Ken's:
1966 Super Wagoneer
5.7L 2BBl. Th700R4. NP-208. Opens. 3.31s. 4core. 4Discs. PS,PB,AC,CC,Cassette.
(Soon to be TBI)
"If it aint leaking, it's empty!"
Reply With Quote
  #17  
Old 07-24-2013, 08:47 PM
Kenall's Avatar
Kenall Kenall is offline
Moderator
 
Join Date: Apr 15, 2000
Location: Sacramento, CA.
Posts: 2,886
how are your front wheel bearings?

improper adjustment will 'lean' the rotor aginst the pads spreading them apart and cause much pedal travel.
__________________
Ken's:
1966 Super Wagoneer
5.7L 2BBl. Th700R4. NP-208. Opens. 3.31s. 4core. 4Discs. PS,PB,AC,CC,Cassette.
(Soon to be TBI)
"If it aint leaking, it's empty!"
Reply With Quote
  #18  
Old 07-25-2013, 04:17 AM
jamesdart's Avatar
jamesdart jamesdart is offline
Grease Monkey
 
Join Date: Jan 05, 2013
Location: nj
Posts: 389
What are the calipers from? It almost sounds like the pistons are too big for the master cylinder
Reply With Quote
  #19  
Old 07-25-2013, 07:54 AM
Dr. Marneaus's Avatar
Dr. Marneaus Dr. Marneaus is offline
FSJ Maniac
 
Join Date: Jun 16, 2010
Location: Reno, NV
Posts: 2,886
Quote:
Originally Posted by shosandjeep
Doc, when you adjusted the rear brakes, did you tighten the star wheel until you couldn't turn the wheel and tire by hand, then back off the star wheel 10 clicks? Old school method, but it seats the shoes. If you only adjusted until you felt drag, you didn't get them tight enough, especially with unturned drums. Just a thought.

Worth a try right? I just adjusted them to equal resistance
__________________
Quote:
Originally Posted by FSJunkie
Dr. Marneaus is now officially my idol.

The Mag - The Wag

The Beast Build Thread:Marns '73 Wagoneer Thread
1973 Wagoneer - 1987 360 w/ factory 4bbl - TH400 - D20 - D30/D44
Reply With Quote
  #20  
Old 07-25-2013, 07:56 AM
Dr. Marneaus's Avatar
Dr. Marneaus Dr. Marneaus is offline
FSJ Maniac
 
Join Date: Jun 16, 2010
Location: Reno, NV
Posts: 2,886
Quote:
Originally Posted by Kenall
how are your front wheel bearings?

improper adjustment will 'lean' the rotor aginst the pads spreading them apart and cause much pedal travel.

When I rebuilt the axle all was well. Wheel bearings were in good good shape so I reused them. I can pull the wheels and check for proper alignment
__________________
Quote:
Originally Posted by FSJunkie
Dr. Marneaus is now officially my idol.

The Mag - The Wag

The Beast Build Thread:Marns '73 Wagoneer Thread
1973 Wagoneer - 1987 360 w/ factory 4bbl - TH400 - D20 - D30/D44
Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Replacing Brake Shoes..parking brake strut problem? youngjeeper General FSJ Tech 2 08-03-2009 07:22 AM
Parking brake woes spark691 General FSJ Tech 11 05-07-2009 02:44 PM
no brake or tail lights..but turn signals! (EDIT:FIXED!) griffsyj General FSJ Tech 6 03-24-2009 10:22 AM
72 Wag: "pressure" affect brake lights? fredg78741 General FSJ Tech 5 02-18-2008 01:00 PM
Park Brake Problem RAMBLINFSJ General FSJ Tech 4 09-03-2007 12:31 PM


All times are GMT -6. The time now is 08:58 AM.


Powered by vBulletin Version 3.5.4
Copyright ©2000 - 2020, Jelsoft Enterprises Ltd.
corner corner