91 Land Cruiser Brake Problems

[Dtrain00]

Alright guys, I did some searching and am still at a loss for what might be going on (even more so maybe).

I bought a 91 about 4 months ago to drive while I am working on my 60, so I have no reference of how the brakes were before. That being said, here is what is going on:

With the car off, the pedal will go about half way down before getting hard, even after pumping. With the car running, I can push the brake pedal down about half way before there is any pressure, then if I hold it the pedal will go down incrementally (little jumps at a time if you will) until almost to the floor. Driving down the road at any speed, I can literally smash the pedal with both feet and I cannot get the brakes to lock. The car will stop, but not fast at all.

Here is everything I have done so far:
Bled system (including LSPV)- still the same
Replaced rear shoes and adjusted, re-bled - still the same
Bled again - still the same

At this point I got frustrated and thought I may have a MC issue so I took it to the shop (not dealership). They were not 100% sure what the issue was so they drove it around and agreed it was not right, so they inspected some things.

They found I had a small amount of fluid behind the dust boot of one of the wheel cylinders, and that was about it.

They bled the system and no air was found. To try to rule some things out I had them replace the wheel cylinders, MC, and front pads/turn rotors, and check that the lines were all good.

Everything is still the same, so the issue was not the MC. Now the theory from the shop is the booster. I have good vacuum to the booster. If I remove the vacuum line to the booster with the engine running the pedal heights are the same, although the pedal becomes very hard to push. Stopping ability is the same at low speed (I wasn't going to test it out going very fast).

Doing the forum searches people have also mentioned bearings being worn and a few other things, which was not something I even considered. There does not appear to be any wiggle in there, but I have been proven wrong before.

Before I throw any more money at this thing I was hoping somebody has run into this before. Any help would be appreciated.

-D

 

[chairborne]

I'm in a similar situation with my terrible brakes. I pulled the boot off of my LSPV and found it was full of fluid. I have replaced the LSPV and my brakes are better but I still have to bleed all the air out of them. I am thinking I need to replace the soft lines next.

 

[Dtrain00]

So could it be an LSPV problem?

I was at the point where I was just going to replace the booster and lines and figured that one of those would have to solve the problem with them being the last real brake components that could be causing the problem.

After reading some people had better braking once they replaced bearings, and now not knowing what else could be causing it, I am at a bit of a loss.

 

[Springs505]

My 91 has a similar, squishy feel even after a complete fluid swap. I am considering replacing soft lines. I think the lines deteriorate and begin to stretch under pressure. I am pretty sure I have read threads where people say they got a good improvement from this.

I have not done this yet, but plan to soon. Good opportunity to get extended lines if you plan to lift later.

 

[jvazquez53]

My 91 has a similar, squishy feel even after a complete fluid swap. I am considering replacing soft lines. I think the lines deteriorate and begin to stretch under pressure. I am pretty sure I have read threads where people say they got a good improvement from this.

I have not done this yet, but plan to soon. Good opportunity to get extended lines if you plan to lift later.

Mine were like that, bled, bled, bled the system and that solved the problem. Even minute air bubbles will make the different between well bled brakes and a lousy brake bleeding job. It took me a good hour to do it, did it alone with one of those $8.00 one man bleeder systems. Cheap but works.

 

[Michael Hanson]

Hi, My 1991 takes forever to bled. Keep trying. Mike

 

[jvazquez53]

Hi, My 1991 takes forever to bled. Keep trying. Mike

X2. Takes a long time, easy one hour +...

 

[Dtrain00]

I'm open to trying to bleed some more...

I've put about 4 quarts through it, and then the shop did it to. So with that said, I can use the two person method, or I have a mighty vac...is there a specific way I should do this? Meaning, how long do I stay at each valve and continue to bleed? Or do I just go round and round until I run a couple more quarts through it?

Thanks again guys.

 

[jonheld]

About 70% of your brakes come from the front.
Have you rebuilt the calipers?
What shape are the rotors in?
Are the soft brake lines original (22 years old)?
Is the EGR/vacuum system in good shape?

The rear shoes stay in adjustment by regular use of the handbrake, assuming the adjuster mechanism is functioning properly and the static setting of the handbrake is correct. Same rear brake setup as a 60. Handbrake should go 5-7 clicks max.
Correctly adjusted rear brakes will give you a firmer pedal.

All of these will effect brake feel and pressure.

FWIW, I have never had an issue bleeding brakes on my truck using a Snapple bottle and a length of clear tubing. It's a simple system with no ABS. Put a block of wood under the pedal to avoid going to the floor and pump away.

 

[jvazquez53]

I'm open to trying to bleed some more...

I've put about 4 quarts through it, and then the shop did it to. So with that said, I can use the two person method, or I have a mighty vac...is there a specific way I should do this? Meaning, how long do I stay at each valve and continue to bleed? Or do I just go round and round until I run a couple more quarts through it?

Thanks again guys.

Try the one man bottle, cheap and works if you follow the instructions.

 

[M32H32is]

FWIW the brakes on 80 series are horrible.

 

[Douglas S]

FWIW the brakes on 80 series are horrible.

I'm going to go ahead and assume that you haven't upgraded your front brakes to the 93-97 calipers/rotors.

 

[Dtrain00]

About 70% of your brakes come from the front.
Have you rebuilt the calipers?
What shape are the rotors in?
Are the soft brake lines original (22 years old)?
Is the EGR/vacuum system in good shape?

The rear shoes stay in adjustment by regular use of the handbrake, assuming the adjuster mechanism is functioning properly and the static setting of the handbrake is correct. Same rear brake setup as a 60. Handbrake should go 5-7 clicks max.
Correctly adjusted rear brakes will give you a firmer pedal.

All of these will effect brake feel and pressure.

FWIW, I have never had an issue bleeding brakes on my truck using a Snapple bottle and a length of clear tubing. It's a simple system with no ABS. Put a block of wood under the pedal to avoid going to the floor and pump away.

I have not rebuilt the calipers, but they appear to be in good shape and I had the shop check them out to be safe since I was replacing the wheel cylinders.

The rotors were new from the last brake change the previous owner did, and I had them turned with the pad change.

I have good vacuum, but I can pull the EGR and clean everything as well.

The brake lines I am going to assume are probably the original to the rig. I think that might be what I replace next.

I am positive the rear brakes are adjusted right. I did them with no improvement, and then the shop tore everything apart and put them back on/adjusted with the same result. I also believe all the air is out of the system.

 

[Dtrain00]

So I had a bit of time and checked out the egr and looked over all the lines (could still be a problem, but couldn't find anything). I swapped out the booster with no improvement.

I'm not ruling anything out yet, but leaning more and more toward believing that the 80s brakes just suck. I may swap out lines, but not sure if the money will be worth it.

 

[jonheld]

FWIW the brakes on 80 series are horrible.

Wow. Uhhh no. I have the OEM setup on my 91 with the original calipers, original rear drums, original rear cylinders, OEM Toyota lines all around, OEM rotors and EBC Greenstuff pads up front. I can chirp tires on dry pavement with new 33s.

Brakes need to be thought of as a system, not just a bunch of parts. If you neglect the system then it won't operate to specification. It's pretty simple really. If you take care of your junk it will work properly.

If the EGR and vacuum modulator on your 3FE is 21 or 22 years old, then it's done. There is almost a guarantee that it's leaking vacuum internally because IT'S 21 FREAKIN' YEARS OLD. Parts wear out and need to be replaced.

You're just THINKING of replacing soft brake lines that are 21 years old? Congratulations on that small piece of logic.

You didn't have the 21 year old calipers rebuilt for $30 in parts? Do you really think that's a good idea??????????

C'mon fellas. Stop with the nonsense. Your truck is either safe to drive or it's not.

 

[Springs505]

I'm going to go ahead and assume that you haven't upgraded your front brakes to the 93-97 calipers/rotors.

I have seen something on this before, but never looked at this seriously. If you do end up swapping to the FZJ front brakes, remember that they require 16 inch wheels to clear the caliper, so you may have to do this first.

 

[Effjay80guy]

Wow. Uhhh no. I have the OEM setup on my 91 with the original calipers, original rear drums, original rear cylinders, OEM Toyota lines all around, OEM rotors and EBC Greenstuff pads up front. I can chirp tires on dry pavement with new 33s.

Brakes need to be thought of as a system, not just a bunch of parts. If you neglect the system then it won't operate to specification. It's pretty simple really. If you take care of your junk it will work properly.

If the EGR and vacuum modulator on your 3FE is 21 or 22 years old, then it's done. There is almost a guarantee that it's leaking vacuum internally because IT'S 21 FREAKIN' YEARS OLD. Parts wear out and need to be replaced.

You're just THINKING of replacing soft brake lines that are 21 years old? Congratulations on that small piece of logic.

You didn't have the 21 year old calipers rebuilt for $30 in parts? Do you really think that's a good idea??????????

C'mon fellas. Stop with the nonsense. Your truck is either safe to drive or it's not.

Is there a way to check vacuum or the egr valve to see if it's within spec. I have a hard peddle and have read the treads on this and before I get into a booster I would like to know about any vacuum tests. Also I have been running strong with the new dizzy so thanks for your help on that.