Brake Problems!!

I have a freind who just completed putting 8 lug Ford running gear under his 2000 XJ and is having front brake problems now. He put on new, Calipers, pads, braided soft lines, stock hard lines and rotors along with a new Stock xj brake booster( double diaphram ) and a 1 ton master cylinder. The prob he is having, is his front brakes will slowlly , in about 15 minutes of steady driving and braking, bind up on him and not release as they are suppose to causing the jeep to slowlly lock up. Does anyone have any idea as to what maybe going wrong.
Thanx Digger

start with the brake booster rod adjustment between the master cylinder....probibly too tight.... That will cause the brakes to drag and lock up.

OK , thanx RC, that also brings back another thought. He has an air leak or vaccum leak between the booster and the master. Could this be helping the problem?

the rod in the master cylinder that goes to the booster is expanding as the engine is heating up causeing the brakes to seem like they are not realesing are you sure u have the correct master cylinder and it isnt recomended to try and play with that rod(could cause no brakes if adjusted incorrectly

Mothertrucker said:

the rod in the master cylinder that goes to the booster is expanding as the engine is heating up causeing the brakes to seem like they are not realesing are you sure u have the correct master cylinder and it isnt recomended to try and play with that rod(could cause no brakes if adjusted incorrectly

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i has been stated that he has installed a 1 ton master thus almost always requiring playing with your rod (hahha) the rod is extended too far out and does not allow the master to release pressure try shortening the rod 1 to 1/2 turn at a time and see what works best you want the rod out as far as possible without causing auto locku (also no slop between rod and master) the vacume leak will also make a huge difference in the power he has while braking i had about an 1/8" hole in mine it it felt like i had turned the engine off (rock hard brakes with no stopping power)

edit: on mine i had to get a new rod that was slightly longer (bolt wiht the head ground off.) i have a dual diaphram booster wiht e350 master

If the master cylinder is new(or at least clean) and with new fluid,you should be able to see the piston cup/valve and the porting.You can use this to adjust the rod.