Brakes locking up while driving **NEED HELP ASAP**

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2tirefire
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I need some help from the NICO members to get my car back up and running. Here is the problem I am experiencing, followed by what I have done to try to correct it.

About 2 weeks ago I was driving down the road as normal and my brakes started to start dragging, then another mile all four of them locked up completely? The pedal got very, very stiff and I could hardly move it off the road. I let it cool down and then popped the front bleeders and all was normal again, till I tried to use the brakes again, then the same thing happened and I had to repeat the above process.

I just replaced the Brake Master Cylinder thinking that may have been the problem with an OEM one, not a cheap auto store replacement. I bled all of the brakes and did a full fluid flush and replaced with all new fluid. Everything seemed dandy until I got driving for about five minutes, then the brakes started to drag, and then all for of them locked up again...I am pissed now. I did noticed that once I let it sit for a moment and pump the brakes while the car was off, it did release some pressure from the calipers so I could roll it home, not using the brake pedal only the Ebrake.

Could someone please give me some advice on what I need to do to solve this problem? I have already replaced the 2 front calipers since they were shot when I bought the car, and the pads are brand new on all 4 corners. I just can't think of why all of my brakes will start dragging simultaneously then they will just lock and need to be manually bled to release pressure, or continuous pumping when the car is off to release a bit of pressure. As you can tell this is not safe.

Thanks in advance.

Mark Ryals


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mrzabala
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hmm had problems with other cars. Just a basic step by step. -block the wheels-Jack it(make sure you do it right). -Make sure its safe with jack stands. -Remove the wheel.-hopefully you have a c lamp? If not, a clamp will probably work. Or go buy one.-Remove your caliper(straight foward for you I hope)And Im pretty sure your pads are pressed in.-Use your c clamp and put one side on the caliper and one side on the pad. Then clamp it so that it pushes the pads back to its spot when no brake is applied. Do this for all 4 sides. Now just go in reverse and install everything back. and it should solve your problem.If not than its either your fluids or brake cylinder/booster. But I've havent had time to go into it myself. Good luck and I hope you get it fixed. Make sure you dont drive it too far until your sure its okay. Wouldnt want you to lose brakes and crash or get it stucked and get reared.

2tirefire
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mrzabala wrote:hmm had problems with other cars. Just a basic step by step. -block the wheels-Jack it(make sure you do it right). -Make sure its safe with jack stands. -Remove the wheel.-hopefully you have a c lamp? If not, a clamp will probably work. Or go buy one.-Remove your caliper(straight foward for you I hope)And Im pretty sure your pads are pressed in.-Use your c clamp and put one side on the caliper and one side on the pad. Then clamp it so that it pushes the pads back to its spot when no brake is applied. Do this for all 4 sides. Now just go in reverse and install everything back. and it should solve your problem.If not than its either your fluids or brake ylinder/booster. But I've havent had time to go into it myself. Good luck and I hope you get it fixed. Make sure you dont drive it too far until your sure its okay. Wouldnt want you to lose brakes and crash or get it stucked and get reared.
Dude thanks for the reply, I appreciate it. I have already popped off the wheels and did some test by applying brake pressure and being sure that the caliper would release afterwards, and it does. But driving it is a whole different story, the pedal will start getting harder and harder, and the car will start feeling slower and slower, then bam the car will just lock up!! It is very weird.

I thought it was the master cylinder not releasing pressure when the brake was let off, but that seems not to be the problem. It couldn't be the calipers since each one is independent on it's own brake line, and it happens on all four corners of the car. I know brake systems fairly well, and I am seriously confused on what it could be.

Could there possibly be something with my brake booster? I have never heard of a brake booster causing this kind of problem, but possibly it could be stuck in and not returning keeping full lock on all four corners? Help is needed and much appreciated!

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mrzabala
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Ouch, Im in the same boat you are. Sorry that I couldnt help. I dont recommend shops or the dealer ship because they might just replace something to charge you $$$ and might not solve the problem. I think asking local shops that specialize in brake system about the problem and getting advice and guidelines would help. Have you checked under the dash to see if everything is okay? The cars I work on have a spring that holds the brake pedal and retracts after releasing the foot. Hope it gets solved. And if you get it fixed maybe thread it so that people in the long run would be able to know and fix the problem

180fan
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Did you check the grease on your caliper pins? It's the pin that slides into that bracket that the two bolts bolt into to hold the caliper.

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benemorius
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Are you certain that all four are locking? Make 100% sure, because that is improbable.

Something like this can be caused by a kink in a hardline. The kink allows pressure from the master cylinder through to the calipers, but won't allow it to release back to the master cylinder. The result is that with each pump of the pedal you are locking more and more pressure into your calipers until they lock up. Opening the bleeder screw releases this pressure, then it starts all over again.

2tirefire
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benemorius wrote:Are you certain that all four are locking? Make 100% sure, because that is improbable.

Something like this can be caused by a kink in a hardline. The kink allows pressure from the master cylinder through to the calipers, but won't allow it to release back to the master cylinder. The result is that with each pump of the pedal you are locking more and more pressure into your calipers until they lock up. Opening the bleeder screw releases this pressure, then it starts all over again.
Dude thanks for the info, I never thought of a kink being in a hardline. I am almost positive that it is at least both front Brakes since they will be hotter than hell and will sizzle when I spit on them to see for hotness. The back ones seem to be locking up also, but I am only 80% sure, but they seem to get really hot also.

Where would I start with the hard lines? Should I trace them all back from the master cylinder to the brake calipers. What should I exactly be looking for? That might explain why it happens over time and then when I give it a rest it will let me drive again. Please let me know what I should be looking for, thanks again man for the great info!

2tirefire
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I went ahead and drove the S13 around today and sure enough was able to recreate the problem. And I did verify that all rotors were soaked in heat from dragging. Could this be from possibly the brake booster getting stuck when the brake pedal is applied? I am at a loss of words at this point. I mean the brake system is not overly complicated. You have Booster to Master, Master to lines, and lines to calipers. What gives!

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ricebike
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hmm maybe a bad massa cyl from the parts store...

how was the hard lines & rubber hoses to the calipers?

u checked the one way valve & brake booster test to rule that out?

180fan
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yikes all 4? I'd check the master. A kink in a hardline would result in a pair of them gettin locked up, but not all 4. That'd be somethin up with the master or like you said, the booster holding the pressure on the master. You put grease where the booster meets the master?

2tirefire
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180fan wrote:yikes all 4? I'd check the master. A kink in a hardline would result in a pair of them gettin locked up, but not all 4. That'd be somethin up with the master or like you said, the booster holding the pressure on the master. You put grease where the booster meets the master?
How do you test if the brake booster is going out? I have a suspicious feeling that the booster is holding pressure down on the master since I can let it sit for a few minutes and then pressure will release.

If someone can let me know how to test if the brake booster is bad I would like to know since, I need to get my car up and running again. Thanks guys.

vvaffle
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Try to see if pressure builds up with the car off. As far as I know, the booster doesn't do much while the car is off.

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ricebike
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d/l the FSM for the win?

i'mma stepping out for a bit/ gotta return a defective exhaust to NC...

but if everything else checks out/ u may have a bad master cyl from the sto!

2tirefire
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180fan wrote:yikes all 4? I'd check the master. A kink in a hardline would result in a pair of them gettin locked up, but not all 4. That'd be somethin up with the master or like you said, the booster holding the pressure on the master. You put grease where the booster meets the master?
When I cleaned the master cylinder I sprayed some brake cleaner in the hole where there was a bunch of flaked paint and dirt to clean off that area. Is there a specific place I need to put grease on the brake booster?

I will look in the FSM to see if there is a way to test out if the brake booster is good.

Q45tech
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AH! Brake Cleaner inside where it's not supposed to be............secure a brand new master cylinder. I knew this sounded familiar happens frequently when untrained put PS or other liquids in Master cylinder refill or somehow plenum cleaning solvents get sucked into vacuum booster and migrate.

Self-mortification with a leather flail is sometimes useful.


2tirefire
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Q45tech wrote:AH! Brake Cleaner inside where it's not supposed to be............secure a brand new master cylinder. I knew this sounded familiar happens frequently when untrained put PS or other liquids in Master cylinder refill or somehow plenum cleaning solvents get sucked into vacuum booster and migrate.

Self-mortification with a leather flail is sometimes useful.
Did I damage the seals in the master cylinder while putting brake cleaner into the master cylinder? Are you sure I will have to replace it, or how can I check if it was damaged. Thanks for the info.
Modified by 2tirefire at 4:15 PM 8/14/2006

Q45tech
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I don't know for sure just reporting historical facts, never seen anyone use spray brake cleaner inside a brake system.

2tirefire
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Q45tech wrote:I don't know for sure just reporting historical facts, never seen anyone use spray brake cleaner inside a brake system.
Man you had me ****eing my pants:). I believe it is ok in small doses. The only reason they advise against it is the Petroleum base drying out the seals..

NEW INFO!!! Ok so I went outside and drove the car around and waited till teh brakes locked up, I finally got them to lock up and here is the kicker. If I pull off the Vacuum hose from the brake booster...the damn thing starts to roll like normal!!!! WTF!!! Is that a clear indication of the brake booster not working and I need a new one? Also I see that there is a check valve of sometype between the engine and the brake booster line, could that be broken and keeping the brake booster shut? Thanks fella's hopefully this helps out someone in the near future!

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ricebike
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mebbe if you let some time for the cleaner to evaporate 1st...

isn't the massa cyl under lifetime warranty anyways? (w/ receipt of course)

did the pdf FSM gave u the booster and one-way check valve tests? i didn't d/l it yet since i'm temp on my bro's laptop...

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benemorius
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2tirefire wrote:Is that a clear indication of the brake booster not working and I need a new one?
Why yes - yes it is. Unless your pedal is sticking... but it would have to be really damn sticky to do that.
2tirefire wrote:Also I see that there is a check valve of sometype between the engine and the brake booster line, could that be broken and keeping the brake booster shut?
No indeed.

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ricebike
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if that one-way check valve was shot, your booster wouldn't be holding pressure @ all & would force u to use your leg muscles to stop da car...

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rotorimp
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Booster looks most likely to be the culprit. when you start the car the pedal should let down a bit. and should pump up with the ignition off.

NISTECH
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Make sure your brake pedal is adjusted properly and the booster rod is set properly. It could be its holding slight pressure on the master. As the brakes start of heating they start dragging even worse. Also the brake booster itself has a rubber diaphram in it. Spraying brake clean in the whole will damage that diaphram.

dwnshfter
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ok, i know this is old as ****, but i am having the same problem. my booster was filling up with fluid and i got a new one from the junkyard and replaced it. it has worked for about a week now and now i am having the same issue. all 4 brakes lock up and i cant even push the pedal down. so do i need to bite the bullet and buy a new one from the part store for $150 or what? i didnt grease the master cylinder before i put the new master on. also i replaced the master, but i user one from the junkyard also.....

dwnshfter
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was my check valve on the brake booster.

s13_boss
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dwnshfter wrote:was my check valve on the brake booster.
that was the culprit?

I'm having the same problem now, but I found out that if i lift the pedal with my foot, the car rolls, so this whole time I was thinking that it could be a misadjusted brake rod.

does anyone know the factory specs of the brake rod adjustment?

Mfeng
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2tirefire wrote:I need some help from the NICO members to get my car back up and running. Here is the problem I am experiencing, followed by what I have done to try to correct it.

About 2 weeks ago I was driving down the road as normal and my brakes started to start dragging, then another mile all four of them locked up completely? The pedal got very, very stiff and I could hardly move it off the road. I let it cool down and then popped the front bleeders and all was normal again, till I tried to use the brakes again, then the same thing happened and I had to repeat the above process.

I just replaced the Brake Master Cylinder thinking that may have been the problem with an OEM one, not a cheap auto store replacement. I bled all of the brakes and did a full fluid flush and replaced with all new fluid. Everything seemed dandy until I got driving for about five minutes, then the brakes started to drag, and then all for of them locked up again...I am pissed now. I did noticed that once I let it sit for a moment and pump the brakes while the car was off, it did release some pressure from the calipers so I could roll it home, not using the brake pedal only the Ebrake.

Could someone please give me some advice on what I need to do to solve this problem? I have already replaced the 2 front calipers since they were shot when I bought the car, and the pads are brand new on all 4 corners. I just can't think of why all of my brakes will start dragging simultaneously then they will just lock and need to be manually bled to release pressure, or continuous pumping when the car is off to release a bit of pressure. As you can tell this is not safe.

Thanks in advance.

Mark Ryals
I got the same problem as you have with my 2005 Hyundai Elantra! I changed the master cylinder and caliper with the dealer and firestone, but the problem comes again after two months drive...I take the car to firestone and dealer again and they check there is nothing wrong with the parts. The car drives normal in local, but if I drive on the highway, the brakes pedal becomes harder, and the car drags and can not drive in high gear.

Does anyone had the same problem and now solve??

dracodrift
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http://garage411.com/BrakesS13 this might help im having the same problem and this is my next move plz post if it works :dblthumb:

dracodrift
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mine are working now and make sure that your brake light switch gives your pedal enough room to come up it helps :rotfl

Jme27unc
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HEEELLLPPPPP!!!!! Has anyone fixed this problem? I'm have the same issue as we RIGHT NOW. I drive the care on the highway for about 10 to 15 minutes and the car starts to drag with the brake pedal hard as heck!


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