Hard braking sudden failure?

[josefgabriel]

Hello. So tonight on my way to the auto parts store to fix the latest in a long string of issues with my FJ62 I almost blew through a stop sign and had to brake pretty hard. Just enough to barely chirp the tires and only going about 30 but right after that it was like my brakes were not working hardly at all. They seem to work fine when braking a little but as you begin to add pressure it gets progressively harder. The first thing I checked was the fluid level and for leaking at the master cyl but did not see anything. Nothing visable on the front rotors from walking around the truck and the drums are not visable. Money is extremely tight right now and I need the vehicle to get to work. It is late now and when I get home tomorrow I thought about bleeding the brakes but are there any other suggestions I might try? As much as I fear robbery I thought about maybe taking it to somewhere like brake check where they give you a "free" inspection. I had the brakes completely redone (well as far as I can remember...it was like $800) a couple of years ago and thought I would be good for a while.

 

[Michael Hanson]

Prob. the brake booster.Find someone to rebuild it. mike

 

[josefgabriel]

Thanks. Still looks expensive but I found the test for it on here. I will try that tomorrow and if that is it just suck it up. Looks like Wimberly 4x4 in New Braunfels might be a good choice.

 

[rover67]

I just picked up a used brake booster off of a 94 4Runner at the junkyard for $25.

May want to visit a few junkyard or call around. Mine started doing the same thing and I hope to get the booster installed this weekend. I guess the 4 runner booster is supposed to provide more boost. We'll see.

 

[Randy88FJ62]

Jose,
I upgraded my brakes last year to discs in the rear. Because of this I had to upgrade my MC. I now have my stock old diaphram and master cylinder laying around in my garage. It's yours for free if you pay shipping. email me at randy88fj62atyahoodotcom. I can ship it out tomorrow.
-Randy

 

[josefgabriel]

Randy,
What years can I use from the 4 runner? I am going to call Wimberly 4x4 tomorrow which supposedly has a massive graveyard of cruisers (from what a friend told me) and maybe 4 runners? And is it Josef .

I did the test for the brake booster at lunch. Here are my results:

1. Depressed brake pedal with engine off. No change in distance.
2. Started engine with pedal depressed. Pedal went down slightly.

So those two seemed to pass. Second part. Air tightness:

1. Started engine and let iit run. Depressed pedal several times. Seemed to go down the same each time.
2. Depressed pedal and turned off the engine. I could actually feel the pedal go "up" (toward me) a little. It held its position.

I have had a master cyl go out and it doesn't feel like that. It isn't spongy but it takes progressively more pressure to stop the beast. Slowing down quickly is a bit scary and I know I need to have this thing fixed this weekend if possible.

Just posting to see if it still seems the most likely culprit. We just moved so my service manual is buried somewhere but from what I have read this isn't any easy procedure? I traced the brake lines looking for possible vacumn leaks and it seems like the booster os over between the oil filter and the AC compressor? Thanks always for the advice and as much as I hate being back in Texas this Wimberly 4x4 thing sounds like it might be a blessing.