Im ready to just light it on fire!

Well Im lost here. I am having a major brake problem!

Pedal goes to the floor but grabs right at the bottom about an inch before the floor.

Here is the info,

I have a 2001 xj that I just did a front and rear axle swap, Front high pinion 44 and xj 44 rear. I left the brake lines open outside while the jeep was going through this transformation. It has stainless brake lines front and rear so I couldn't clamp the lines with anything. The lines were open for 4 months or so.. The front has NEW ford calipers, pads and rotors. Rear has new shoes, brake hardware springs etc and wheel cylinders. Now the back drums are original and I have no emergency brake hooked up. I also did not put in the cross bar at the top but below the springs.
I adjusted the shoes out to where the drums would just barely slide on.

Ok so I bleed all 4 corners Pedal is good and hard I start the jeep and pedal goes strait to the floor? I bleed 3 bottles thru and still when I start the jeep pedal goes to the floor....I have sprayed brake cleaner and dried around all the bleeders lines etc. No Leaks At All! This xj had abs so I heard that the abs pump could be holding air so I did the abs removal with one line from prop valve to the rear line and front lines to a T and to the prop valve. I bled all 4 corners again and still to the floor???? I thought maybe the master cylinder is bad.. So I removed it and replaced it with the 2003 durango which has the larger bore. I bench bled it perfectly no bubbles at all. Put it in bled all 4 corners and even gravity bled it still to the floor?????????????


Please help any and all comments or suggestions would be greatly appreciated.

Im freaken pissed and sometimes not sure how I have so much passion for this damn jeep!! I guess thats what makes us real jeepers.

Calipers on the correct side?

Bleed ports must be on top.

Yes sir they are. maybe the booster rod needs adjusting? Will that make a difference about it going to the floor???? Or do I need new drums?

without being there it is impossible to say but it really sounds like you need to bleed everything again. how are you bleeding the brakes: gravity, vacuum, one guy push the pedal while one opens the bleeder, etc?

I have done the buddy method with taking care they don't pump to hard and also the gravity method?

crystalcleanteam said:

Now the back drums are original and I have no emergency brake hooked up. I also did not put in the cross bar at the top but below the springs.
I adjusted the shoes out to where the drums would just barely slide on.

Click to expand...

i would take a look at the way you set up and adjusted the drums.

did you setup the drum hardware to oem spec? im confused about the crossbar setup. is the crossbar where its supposed to be? off the top of my head i cant remember where the crossbar is supposed to be, but why do you mention its below the spring and not above? can it go either way?

as for the adjustment, with the drum and wheel on and with one wheel off the ground at a time, use a flat head screw driver in the adjustment slot on the back of the drum and manually adjust the shoes so they drag slightly when you rotate the wheel.

I have to agree... it does sound like you have trapped air although by now you would expect it all to be gone....
Since you have bled the brakes countless times with the vehicle off; try bleeding the brakes with the vehicle idling so that you are using the vacuum booster when stepping on the brake pedal.
The last recourse would be to have the brakes power flushed where they attach a cap on the top of the master cylinder and use a machine to pressure fill the system while opening the bleeder screws.....
Many years ago I did a disc brake conversion and bled the system countless times and couldnt get all the air removed; finally resorted to going down to the local Goodyear and having them pressure flush the system. No more problems and the brakes work great.

It could be that your master cylinder is too small of a bore for the brakes you have. It simply does not move enough volume of fluid to quickly engage the pads/shoes. If this is not the problem then you probably are not bleeding them correctly or the master might just be bad.

I don't know, if it bleeds out good and you have good pedal before you start the motor, I doubt it's a bleeding problem. I also doubt it's an adjustment problem. If you get a firm pedal when the motor is off then you should get a firm pedal when the motor is on.....if it's an adjustment or bleed problem. Not being there, who really knows. I'd look at the things that change once the motor is running, like the ABS and the booster.

Will the brakes pump up?

If the pedal is spongy--that means air or really bad flexible lines.

If the pedal is low but hard--that would seem to indicate the rear drums are not adjusted correctly, or possibly as mentioned earlier the bore is insufficient for the brake setup you have.

I used plugs to block off ports starting with the master cylinder pedal on/off rock hard.

Then blocked off at the prop valve pedal on/off rock hard.

Then blocked off rear output at prop valve so only front calipers were connected. Soft and to the floor? So I went one step further and blocked One front caliper at the T I made when removing the abs Pedal was a little better but still if waited a few seconds it went strait to the floor???? No leak at the caliper or connection of the hard line and s/s line. But I did find at the T that I put in if I put my finger under the thread of the plug for the other front caliper a drop of brake fluid.. Not dripping or spraying though. Is that enough to let air in??

Yes. If fluid can get out, air will get in. Spray it down with some brake cleaner and try again, see if there is more fluid on the fitting or if it's just residual mess from when you put it together.

If fluid comes out then air can get in. Were you able to get a good bleed on the suspect caliper?

Another possibility is that the caliper is sticking and the piston isn't returning. You might want to pop the caliper off, see if you can manually push the piston back down, look at it while somebody else presses and releases the pedal, etc