Help! Brake problem...

[fullspectrum]

My Samurai has a problem I've never seen before. I'm thinking water in the brake lines is causing it but I bled the brakes already at all for corners. After I drive it a few kilometers the brakes start grabbing and finnally get so hot I can barely move the truck! It seem like all for corners are hot. I had a spongy low pedal before. Now after I bled them I have a nice firm high pedal. I'm thinking I better flush the lines again. Does anyone have any ideas what is causing this? Water or something else. The truck sat for years before I got my hands on it.

[Evolvocane]

Booster could be taking a shit. Holding pressure on the master.

[TheSarg]

did u bleed that cute lil valvie on the pass side inner frame rail at the back too?

[fullspectrum]

Booster could be taking a shit. Holding pressure on the master.

Never thought of that. They don't grab when cold though. When off the ground I can easily spin a tire without any effort. This is seriously pissing me off. :roll: I had to pull over after 10 minutes of driving to let my brakes cool off. They were almost locked. Would water in the brake lines cause this? I would just figure it would have a spongy pedal then, but my pedal is high and rock hard now to the point of being very touchy.

[fullspectrum]

did u bleed that cute lil valvie on the pass side inner frame rail at the back too? No I didn't bleed that cute lil valvie on the pass side inner frame rail...Proportioning valve?

[Buggy]

i assume you never had it on the road before?do you know the history of the suk i have seen bad boosters do this too. un hook and block the vacuum line too the booster see what it does unless you have a spare to try. the front calipers are known for sticking i rebuilt mine for less then 20 bucks. are the back brakes Turing freely? there should only be a slight drag for proper set up. e brake stuck on? worse come to worse why was it parked? for this problem? power steering oil, trans oil in the system over time swells the seals and will either make the petal go spongy or make the brakes stick on.also the rod between the booster and master clyinder too long do this too

[Evolvocane]

Never thought of that. They don't grab when cold though. When off the ground I can easily spin a tire without any effort. This is seriously pissing me off. :roll: I had to pull over after 10 minutes of driving to let my brakes cool off. They were almost locked. Would water in the brake lines cause this? I would just figure it would have a spongy pedal then, but my pedal is high and rock hard now to the point of being very touchy.


You'll get a spongy pedal with water in the lines. Too low of a boiling point. I don't think you have bleeding problem because you have a hard pedal and your brakes are staying on. Its odd that all four would stick. So I would start with the basics. Check the sliders and make sure the Calipers pistons push back.
Make the proportioning valve isn't holding the rears on and make sure wheel cylinders arnt siezed.

After that I would go after the master and booster.

[fullspectrum]

i assume you never had it on the road before?do you know the history of the suk i have seen bad boosters do this too. un hook and block the vacuum line too the booster see what it does unless you have a spare to try. the front calipers are known for sticking i rebuilt mine for less then 20 bucks. are the back brakes Turing freely? there should only be a slight drag for proper set up. e brake stuck on? worse come to worse why was it parked? for this problem? power steering oil, trans oil in the system over time swells the seals and will either make the petal go spongy or make the brakes stick on.also the rod between the booster and master clyinder too long do this too

I don't really know too much about the history other than it was bone stock. The front calipers look brand new(they were on it) I put new rotors on, pads look fine. The parking brake works fine, all the wheels spin freely when cold. I've basically changed all the fluids everywhere on this truck. I may have not bled enough brake fluid through the lines. It appeared to be bubble and water free. I'm going to run some more fluid through the system and double check those "new" calipers that were sitting with this truck. I'll try plugging the vacuum to the booster and see what happens also. I wanna get this rig reliable so I can hit Raglan...before that place closes too.

[Buggy]

ok you see no signs of water and have a rock hard petal.if you want to check and see if the calipers are releasing properly raise a wheel off the ground spin it get some one to press the brake?is it releasing quickly when they take there foot off the brake? if slow you have a problem and getting your heat problem i even seen bad flex hoses do this what did the old pads look like? wore down evenly? inside pad wore down more then the outside? when the brakes were locked on was the petal low too?

[fullspectrum]

ok you see no signs of water and have a rock hard petal.if you want to check and see if the calipers are releasing properly raise a wheel off the ground spin it get some one to press the brake?is it releasing quickly when they take there foot off the brake? if slow you have a problem and getting your heat problem i even seen bad flex hoses do this what did the old pads look like? wore down evenly? inside pad wore down more then the outside? when the brakes were locked on was the petal low too?

Pads are worn even. When brakes locked the pedal was the same. However it did this before I bled the brakes when the pedal was low and spongy. When the brages started heating up and grabbing my pedal came up. It was still spongy but higher up. I think I must still have crud in the system that is boiling and causing the brakes to grab.

[vanbdan]

Dont know if it helps,but it was parked for years,with the e-brake on.I had to beat on one wheeel to free it up to get it on the trailer.

van:hubba:

[Buggy]

sounds like high moisture problem hard to say how old the brake fluid is how well did you flush the lines? till you got clear liquid? use a mason jar with a hose from the bleeder into a hole in the lid (make sure the hose is in the fluid) crack the line and pump away till you get clear fluid just make sure the master clyinder doesnt go dry. check and see if the brakes are releasing quick when cold because if not it will make the brakes run hotter then normal and with a high mositure level in the fluid of course will boil quicker making the fliud expand and locking up your brakes that why your pedal got hard ?

[fullspectrum]

sounds like high moisture problem hard to say how old the brake fluid is how well did you flush the lines? till you got clear liquid? use a mason jar with a hose from the bleeder into a hole in the lid (make sure the hose is in the fluid) crack the line and pump away till you get clear fluid just make sure the master clyinder doesnt go dry. check and see if the brakes are releasing quick when cold because if not it will make the brakes run hotter then normal and with a high mositure level in the fluid of course will boil quicker making the fliud expand and locking up your brakes that why your pedal got hard ?

I'm thinking this is the problem. High moisture. This truck sat for many years. I probably didn't get all the crap out of the lines. I'll flush the whole system again. Thanks for the advice.

[fullspectrum]

Well I flushed the whole system out and the brakes are still heating up. Everything spins fine when cold and releases ok. Any other ideas what's causing this?

[twistedzuki]

you are getting proper vacume when you run it,is it running shitty now at the same time?

[fullspectrum]

you are getting proper vacume when you run it,is it running shitty now at the same time?

I pulled the vacuum line from the booster after I turned the engine off and there was lots of vacuum. It was running normal for awhile...and now as soon as the choke comes off it starts to stumble and die right away.


Dont know if it helps,but it was parked for years,with the e-brake on.I had to beat on one wheeel to free it up to get it on the trailer.

van:hubba:

I feel like beating the whole truck with a hammer right now :D It's not just the truck...stuff at work and home pissing me off too..yadayada yada..:roll:

[Buggy]

i had a ford do the same thing once work great till it warmed up press the brakes and she lock on it was the booster after the motor warmed up and got more vacuum and wont release properly when you take your foot off the brake.did the brakes release after you took the vacuum line and valve out of the booster? and as for your carb sounds like mine works great cold but after it warms up it wont idle worth crap sooooooooo i took the fast idle solenoid(one that works off of the park lights or heater fan located on the motor) hooked it up to a switch from a separate power on the dash and with some tinkering you can make it idle i did this till i found a pony carb to get me by.

[longy442]

Heres what it is, i'm pretty sure I had the same problem. The rubber brake lines are starting to rot. All the pressure causes them to collaspe on themselves and push the fuild into the calipers. If it locks up you should be able to realease the pressure by opening one bleeder for a second and then be able to drive a short distance until pressure builds up again. You need to replace the brake lines whereever they are rubber. My problem existed on the passenger side front inner fender well were the lines are between the frame and body. I couldn't find replacements so I just used solid lines and looped them. Good luck.

[fullspectrum]

Heres what it is, i'm pretty sure I had the same problem. The rubber brake lines are starting to rot. All the pressure causes them to collaspe on themselves and push the fuild into the calipers. If it locks up you should be able to realease the pressure by opening one bleeder for a second and then be able to drive a short distance until pressure builds up again. You need to replace the brake lines whereever they are rubber. My problem existed on the passenger side front inner fender well were the lines are between the frame and body. I couldn't find replacements so I just used solid lines and looped them. Good
luck.

I just realized somthing...I put brand new longer lines on the front, so I don't think this is the problem. But I never replaced those two rubber ones between the frame and body...

[longy442]

I just realized somthing...I put brand new longer lines on the front, so I don't think this is the problem. But I never replaced those two rubber ones between the frame and body...

That'll be them. I couldn't find the replacement part so I just rigged them up out of steel line with the spring around and looped them so they had some play. I don't think they really have to be rubber. I replaced them and never locked up again. good luck

[fullspectrum]

Well how embarassing is this. I went to Crappy tire for some stuff and it heated up again on the way home. I was in traffic and I was almost locked up solid :( brakes smokin everywhere :roll: So I came home and took the master off. It seemed ok so I took it apart and cleaned it up a bit. I also screwed the thing in on the pushrod to shorten it a bit. Took it out for a fairly long drive after and all seems ok so far. I was riding the brakes to heat them up and no signs of any locking...So I hope this is finally it! Sheesh....:roll:

[Buggy]

well i will tell ya i seen the rod being too long do this i help my uncle do a disk brake conversion on a 66 mustang that had drum brakes and had the same problem set it up to the proper brake pressure and they lock up cut the pressure down below specs no problem but doesn't seem to have the braking power it should don't know why this does what it does but just does lol. maybe this is why it was parked? well wish ya luck and hope it was the problem

[fullspectrum]

I been driving it around for awhile now and brakes are not locking or heating up anymore. :D I guess it was the pushrod length or by shortening it compensated for somthing else..at any rate it seems to be ok now. :D Thanks all for the imput on this. Now on to the other problems...:roll:

[anthony]

my money is on rust and gunk in the master cylinder and the proportioning valve blocking the proper return flow of DOT 3, combine that with corrosion inside the calipers, crap chocking up the pistons and dash of iron oxide on the sliders and voila, too much resistance = friction = heat = lock up .. you can never flush all that crap out no matter what you do

whatever it actually turns out to be rebuild the whole system if it's sat that long .. steel lines rot under the clips and could pop without notice, as previously mentioned the flex lines degrade internally, unexplained warm wheel lockups happen etc etc .. spring the coin and be safe

[fullspectrum]

my money is on rust and gunk in the master cylinder and the proportioning valve blocking the proper return flow of DOT 3, combine that with corrosion inside the calipers, crap chocking up the pistons and dash of iron oxide on the sliders and voila, too much resistance = friction = heat = lock up .. you can never flush all that crap out no matter what you do


I hear ya. Brakes are working fine now. I shortened the pushrod in the master and it went away...The calipers and rotors are new on the front. All new fulid...really flushed the whole system and it still locked up. Not until I shortened the pushrod did it go away. The master was clean inside when I took it apart. I also had new braided flexlines on the front. At any rate I can drive for more than a kilometer now so I'm happy. :)

[anthony]

I hear ya. Brakes are working fine now. I shortened the pushrod in the master and it went away...The calipers and rotors are new on the front. All new fulid...really flushed the whole system and it still locked up. Not until I shortened the pushrod did it go away. The master was clean inside when I took it apart. I also had new braided flexlines on the front. At any rate I can drive for more than a kilometer now so I'm happy. :)

fsteel braid makes the pedal harder .. might be that it took the 'slack' outta the system .. glad you got it sorted