Rotors getting VERY hot

[8thTon]

I went back and read again... while you didn't actually say to take it out... you don't need it. You do say if it leaks a little... no big deal.

Pretty much everything related to your brakes is a big deal... and the OP asked if it should hold vacuum in the booster. The short answer is YES. Not if it doesn't it's OK.

OP... if that new booster won't hold a vacuum... I would buy a new check valve... cheap insurance.

Thank you for showing how ridiculous your statement was. And sure, check valves are cheap and easy, put one on if you think it leaks a bit too much, or just if you think a new one is pretty.

Nothing having anything to do with the booster or check valve can have anything to do with the topic of the thread, which is hot brakes.

 

[Uncle Gump]

Just jack it up and see what wheel is stuck... then squeeze the caliper a bit with a c-clamp and remove it and see if it spins free. It can really only be one of two thing. Bad caliper or bad slides.

Sounds like the booster or the check valve is bad also. But honestly... I see it as two separate issues. Don't think a bad booster or check valve will apply the brakes.

Nothing having anything to do with the booster or check valve can have anything to do with the topic of the thread, which is hot brakes.

I had that part answered back on post 11... why do you keep bringing it up?

 

[8thTon]

I had that part answered back on post 11... why do you keep bringing it up?

When this was brought up in post #7 it seemed the OP was trying to connect it with the hot brakes. I was discussing with the OP that what he was experiencing with the stiff pedal was probably a booster with no vacuum in it, which was not unusual after sitting a long time. Then you felt compelled to tell us how well your check valve sealed, following on with some stupid claim about something I never said.

The symptoms are classic air in the lines and there's nothing else clearly wrong (what is the acceptable engine off leakdown rate of a check valve?), but you've clearly got it under control.

 

[Uncle Gump]

@8thTon ... our discussion is over in this thread. I totally stand behind everything I've said here. If you feel the need to continue this any further... PM me.

 

[8thTon]

@8thTon ... our discussion is over in this thread. I totally stand behind everything I've said here. If you feel the need to continue this any further... PM me.

You stand behind the false accusation? There was no other disagreement between us, and a simple acknowledgement of your error would have sufficed. Hard to see any reason to continue it.

 

[Uncle Gump]

Thank you for showing how ridiculous your statement was. And sure, check valves are cheap and easy, put one on if you think it leaks a bit too much, or just if you think a new one is pretty.

You even acknowledged my acknowledgement..

Let it go man....

 

[NebRanger]

A very quick, not much of an update. The brakes have been acting pretty much the same since my last post, but we got some pretty good snow yesterday, so I took the truck out today on the snow covered streets and hit the brakes pretty hard about 8 times to get the abs engaged. Seems that I have a better pedal feel now, not perfect, but better. Rotors aren't as hot after doing this, and the pedal is more progressive than it has been in a while.
I know I've seen articles of getting air into the ABS module causing a soft pedal, but what I have been dealing with is the exact opposite of a soft pedal. I've seen some, but little, info on valves within the module becoming stuck, and potentially causing a very short, abrupt pedal, which is what I have had.
Anyone here done a bleed cycle with a scanner to cycle the abs module? And if so, what scanner do you have/use.

 

[adsm08]

A very quick, not much of an update. The brakes have been acting pretty much the same since my last post, but we got some pretty good snow yesterday, so I took the truck out today on the snow covered streets and hit the brakes pretty hard about 8 times to get the abs engaged. Seems that I have a better pedal feel now, not perfect, but better. Rotors aren't as hot after doing this, and the pedal is more progressive than it has been in a while.
I know I've seen articles of getting air into the ABS module causing a soft pedal, but what I have been dealing with is the exact opposite of a soft pedal. I've seen some, but little, info on valves within the module becoming stuck, and potentially causing a very short, abrupt pedal, which is what I have had.
Anyone here done a bleed cycle with a scanner to cycle the abs module? And if so, what scanner do you have/use.

Forscan should be able to trigger an ABS service bleed. In the past I usually have used IDS or my Solus, but ForScan will be a much cheaper option for most people.

 

[NebRanger]

adsm08, I appreciate the suggestion. I have been looking into them, as I would like to bleed all the vehicles I have, and , my dads (03 ranger, 01 jeep xj, 05 mini, 2000 boxster, 04 350z). Have noticed the Autel Maxisys Pro and Foxwell NT630, but hard to find what functions they perform on which vehicles, (domestic vs. european vs. japanese).
I work at a local community college in the desl program where we use the latest snap-on systems, but I dont want to rely on a class to work on some things and potentially have vehicles down for however long it may take for the "educational process" to do the work, and dont want to continually ask the instructors for help. Figured as much as I do at home that it would benefit me to just get a decent scanner.

 

[NebRanger]

Another update... I still am having, the same issues, except the brakes are not normally stuck in the morning. I still have a very short brake pedal and VERY abrupt braking, (the brakes come on VERY quickly). Both front brakes seem to act the same way, as the temp on both seems about the same.
A recap of what I have replaced/done... replaced pads, rotors, hubs, calipers, flexible lines, master cylinder, booster. I have bled the brakes 4-6 times, and cycled the abs module multiple times, and bled again. Basically, I have replaced everything in front of the firewall except the abs module and hard lines.
When we did the abs cycle the front end was on stands and the front wheels spun easily.
I have SOMEWHAT gotten used to the pedal travel, but it is really touchy. I am at a loss at this point.

 

[55trucker]

When you did the ABS cycle was everything still hot to the touch?

 

[franklin2]

What I would do is jack the front wheels up when cold and spin them by hand to get a feel for how much drag they have. Then take it for a drive till they get hot, then jack it up again and see how much drag you have. If they have a lot of drag, I would then do some experimenting. While they are still hot and dragging, I would take a wrench and crack the line loose on the master cylinder that feeds the front. Just open it till it spits fluid and then tighten it again. See if that free's the brakes up.

If it does, you know you have a problem with in the master cylinder brake booster area. If it doesn't, crack the bleeder on the caliper itself. If that free's it up, then you know you have a hydraulic problem, you just have to keep cracking lines till you find it. If cracking the bleeder on the caliper itself doesn't free the dragging, you do not have a hydraulic problem, you have a mechanical problem with the caliper or something else down there at the brake area.

 

[Bgunner]

What I would do is jack the front wheels up when cold and spin them by hand to get a feel for how much drag they have. Then take it for a drive till they get hot, then jack it up again and see how much drag you have. If they have a lot of drag, I would then do some experimenting. While they are still hot and dragging, I would take a wrench and crack the line loose on the master cylinder that feeds the front. Just open it till it spits fluid and then tighten it again. See if that free's the brakes up.

If it does, you know you have a problem with in the master cylinder brake booster area. If it doesn't, crack the bleeder on the caliper itself. If that free's it up, then you know you have a hydraulic problem, you just have to keep cracking lines till you find it. If cracking the bleeder on the caliper itself doesn't free the dragging, you do not have a hydraulic problem, you have a mechanical problem with the caliper or something else down there at the brake area.

Just cracking it at the bleeder will tell you this without the need for the line a the master cylinder. If it is a master cylinder/brake booster/ abs system issue, if equipped for front abs, the wheel wheel will turn freely if you crack the bleeder, if cracking the bleeder does not allow the wheel to free up then it is a caliper.

If my memory serves this is just a rabs system and not full abs, this means that just cracking bleeder will be fine and no need to open it at the master cylinder.

If this is a 4 wheel abs then crack a the master first if it releases the wheel it is a master cylinder issue, if not pump the brakes to lock/stiffen it up again then crack the ABS nine to the front brakes if it still is hard to turn the wheel then the Cliper is bad and ABS module is fine. BUT again if my memory of this issue is correct your system is not full 4 wheel abs.

 

[franklin2]

I was just looking for easy places to loosen the lines. You certainly could start at the caliper to decide first if it's a hydraulic problem at all. Thing of it is, I think he said both fronts are doing it. So it would be common to both sides. But I think he needs to start over and jack both front wheels up first to double check they are both doing it, and both doing it with close to the same level of drag.

 

[Bgunner]

I agree with @franklin2 that the first step is lifting both wheels at the same time and checking to see if they drag the same amount is the very first step. Then move on to opening up the system to see if they still drag afterwards.