FJ40 drum brakes kicking my ass!

bigstar

New member
Yesterday I replaced my front drum cylinders on my ‘71 FJ40. I used FC cylinders. Photo included. I can’t get pedal pressure on my brakes! It’s kicking my ass. I adjusted the drums to the point where the wheels wouldn’t turn and then backed off 3 clicks. I put Teflon tape on all 8 bleeder valves. I have a reservoir for the rear brakes and a reservoir for the front brakes. I started at the back passenger side, then went to the rear driver’s side. Then I moved to the front passenger side and finished with the front driver’s side.
I started with the one man bottle with fluid raised about the caliper technique I’ve used on my Dodge several times. No luck. I then used a pressure bleed pump I used on my RS6 to push fluid/air out of each wheel up through the reservoir. I am pushing clean fluid no air. It feels like I am building pressure but then when I get everything buttoned back up I push the pedal and it goes to the floor with little resistance. ******??? I’ve done this several times over the last two days. Any ideas????


Also…… does anyone have a guess on what brand drum shoes these are just by looking? I haven’t seen a part number. Thanks y’all
 

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bigstar

New member
IH8MUD Forum was helpful.…. Something you might respond to…. How about those cool orange recovery track boards mounted on a 4x4???!!!!! Those are SO COOL! ha
 

gwittman

Adventurer
Were you able to get your problem solved? I had a 70 FJ55 on which I eventually rebuilt the entire brake system after having to replace at least 2 wheel cylinders every year. I replaced every rubber item in the brake system, flushed with ethanol and air followed by filling it with DOT 5 silicone brake fluid. I never had any problem with the brakes over the next 8 or so years. I know that doesn't help you much, but I was trying to indicate I know that system. I am sure the FJ40 and FJ55 brakes are similar.

It sounds like you may have air in the master cylinder. I know many master cylinders must be bench bled to get it at the right angle to bleed properly. I don't remember if that master cylinder needs to be bench bled but it is something to consider.
 

nickw

Adventurer
IH8MUD Forum was helpful.…. Something you might respond to…. How about those cool orange recovery track boards mounted on a 4x4???!!!!! Those are SO COOL! ha
IH8MUD is the best forum out there IMO.....absolute wealth of knowledge around the globe.
 

GHI

Adventurer
IH8MUD Forum was helpful.…. Something you might respond to…. How about those cool orange recovery track boards mounted on a 4x4???!!!!! Those are SO COOL! ha
Yesssssss. I love
MAXTRAX MKII Recovery Tracks
Never got stuck again after I got them. No seriously though. Did you get it sorted and what was the fix? Help out the next guy looking for an answer.
 

JasonH

New member
I had this problem once with my FJ40. I ended up using a pressure bleeder that clamps to the master cylinder and forces out to the cylinders. That was the only way I could get it to bleed properly.
 
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NatersXJ6

Explorer
I’m going to guess you’re in bad master cylinder territory. You have a good enough seal to push fluid with open bleeders, but once the pressure starts to build, it blows back pst the master cylinder seal and goes nowhere.
 

bigstar

New member
Well what do you know… I got some replies! Yeah that was a rough week. I had crashed my KTM 1190R Adventure in the desert in Big Bend the previous week so I was dealing with bleeding brakes with a cracked rib…. NOT FUN! ha. So yeah.. I tried EVERYTHING.… bleeding by pushing air out, pulling air out, double jars on each wheel with hoses submerged in fluid, neighbor pumping brake while I bled, bench bleed M/C, bleed M/C on vehicle, aggressively pushing AND pulling brake pedal, etc,etc,etc. I was about to set the thing on fire. And yes I was using Toyota parts. I finally talked to Sonny over at FJParts.com where I got my stuff. He said he had gone through the same thing. He told me to start with the driver’s front, then passenger front, then passenger rear,, then drivers rear ( basically bleed backwards) THEN reverse and bleed the right way. I had my neighbor pumping the pedal. I was skeptical but I did it and it worked! I guess it pushed the air out of it’s hiding spot and got movement. I would suggest this for anyone who is getting their ass kicked by an old Toyota. I had my truck in the shop 3 times in the last couple years and spent over a grand and the brakes were never right. After several days of dicking around with this and bleeding and adjusting with the spoon tool I am a pro with drum brakes. It’s just like it always is….. learn how to do it and do it yourself. NOONE will ever care about your stuff as much as you will. Cheers y’all.
 

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