Rising Sun Member Forums  

Go Back   Rising Sun Member Forums > Toyota 4x4 > General Tech Forum

Reply
 
Thread Tools
  #1  
Old 04-27-2012, 05:06 PM
franktown99 franktown99 is offline
Rock Stacker
 
Join Date: Sep 2009
Location: franktown
Posts: 8
Default fj40, brake nightmare

I have a 1974 fj40 it has new front wheel cylinders, brake hoses, master and front shoes and the problem still has not been corrected. The peddle will pump up feel and hold fine but if you let off for even 15 seconds it will drop and only apply the rears. Any ideas?
Reply With Quote
  #2  
Old 04-27-2012, 06:14 PM
MDH33's Avatar
MDH33 MDH33 is offline
Hard Core 4+
 
Join Date: Mar 2006
Location: Land of Corn
Posts: 5,771
Default

Sounds like they are still out of adjustment (or holding some air). Is the level dropping in the master? Did you bench bleed the master?

It's a pain to get all 4 drums dialed, but once they are, they work pretty well.

I think Jeff Zepp has a good write up somewhere. I used it when I did my brakes about 5 years ago and they have worked fine ever since. (except when my front axle seals leaked and soaked my front brakes in lube).
__________________
--Martin
Reply With Quote
  #3  
Old 04-27-2012, 07:39 PM
PhatFJ's Avatar
PhatFJ PhatFJ is offline
Rising Sun Member
 
Join Date: Apr 2008
Location: Trinidad, CO
Posts: 575
Default

Make sure you put the wheel cylinders in the proper position, they are handed and the bleeders need to be on the top.. This is easy to get mixed up.. Other than this, adjustment and bleeding.. Is the new master toyota? Do you have a FSM?
__________________
KD0GEG
1970 FJ40

trail rig
Trinidad, CO
Reply With Quote
  #4  
Old 04-29-2012, 05:45 PM
black95's Avatar
black95 black95 is offline
Wincher
 
Join Date: Nov 2011
Location: Woodland Park
Posts: 88
Default

I'm the last one you want giving you brake advise, just figured I would throw in that my 40's rear proportioning valve was bad. Caused the rear brakes to always lock up pretty violently even under moderate braking. I have front disks, so not sure if yours has the same factory proportioning valve under the master or not. Worth a look. I put in one from Jeg's, problem solved.
__________________
Luke


-'88 pickup - Daily driver, AAL's, 285's, ARB bumper, Warn winch, all around cool rig.
-'01 cherokee - 6" Long arm'd, 285's, ARB bumper, custom roof rack, electric locked D30, auto locked 8.8, trussed-plated-fortified.
-'12 Jeep JK - 2" lift, Skid Row skidplates, OR fab bumper

KFWD
Reply With Quote
  #5  
Old 05-07-2012, 12:15 PM
Rzeppa's Avatar
Rzeppa Rzeppa is offline
Cruise Moab Committee
 
Join Date: Aug 2005
Location: Kittredge CO, USA
Posts: 5,146
Default

There is no proportioning valve in an all-drum system like franktown99's. Hey franktown, I have a couple of questions for you, we'll see if we can get you headed in the right direction, OK?

Please elaborate when you write "pump up feel". What does that mean?

You wrote that it has a new master cylinder. Did you bench bleed it?

As PhatFJ wrote above the slave cylinders are all different, left top, left bottom, right top, right bottom. Are you 100% sure you installed them in their correct positions?

Good luck! When you've answered these questions, we'll have a better idea of what advice to give you.
__________________
Jeff Zepp
Kittredge CO USA
1971 & 1976 FJ40s, 1978 FJ45, 1987 FJ60
Rising Sun 4WD Club, TLCA #4063
http://american3dprinting.net/
Reply With Quote
Reply

Thread Tools

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

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


All times are GMT -6. The time now is 10:29 PM.


Powered by vBulletin® Version 3.7.1
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.