brake problem 98 transport

this one is driving me bonkers. i have a 98 transport that i have just replaced a front wheel bearing and took it out for a drive and that noise was gone but i felt that the pedal was a bit low, so i took it back to the shop and pulled the rear drums and set the shoes up.and i should mention that the shoes were like new even though they had at least 40,000 miles. put the drums back on and the pedal went right to the floor. i have checked all that i can and i can pump up the pedal and it will hold and it has pedal with the engine off. it ju8st seems too co-incidental that the master cylinder would pick that instance to pack it in.. i should mention also that the rears required very little adjustment and the master was always right to the top with fluid. please respond a.s.a.p. thank you sam

i have been messing around with it for a while and i do now have very low pedaland it will stop the beast when almost when almost at the floor and i further notice that on gravel the left front will lock up but the right seem to be doing nothing floor please help as my wife is on my case sam

At any point was the hydraulic system opened? A wheel cylinder popped open, or brake caliper piston released? If so, you have air in the sysytem that will have to be bled out.
If not, sounds like something is hanging up/out of adjustment, ie brake caliper frozen or rear brakes out od adjustment. If you apply the service brake, then apply the parking brake, does that alter the the feel of the serrvice brake pedal? If the pedal comes up, your back brakes are out of adjustment.
Jeff
Jeff

thank you for the input but at no time was the system ever opened and the fluid was always at the top. i do agree with you that it sound like air but i have no idea why or why only the front left brake seems to be working and it almost seems like the older cars where there was a proportioning valve that kicked in when there was a problem sam

i had thought about trying the parking brake to see if it felt different but it hasn,t been used for ages so i,m afraid of it sticking on and i had adjusted the rear brakes to spec. please keep the idea,s coming sam

have done some more checking and the right front is not braking and appears that one of the solenoid valves in the abs is not opening to allow fluid to get there .. any ideas are greatly appreciated sam

Does the ABS light stay on? And are you sure the brake pedal is retracting all the way, because if not, the compensating port will be closed, not allowing fluid into master cylinder bore to replensish any that was used to extend a piston.
Jeff

Master cylinders do fail....changed my son's Z-34 twice. First time, it was pedal to the floor; second time, one of the rear wheel did not receive any pressure at all from master.
OF course, the "coincidence" is asking for investigation; coincidences do exist ...though cause and effect is my main line of idea... DId you pay a visit again to that front wheel....just in case? I would "bleed " that front cylinder, at least to see if it gets some pressure.
Some suggest very complicated procedures to "bleed" these ABS brake systems...but straight forward traditional method has always worked well with me.

good idea i will take another look at the front. the reson i had not donr before was that it was the other side that needed the wheel bearing and that side was never touched but i will give it a shot thank,s sam

have not got to that front wheel yet. gave up yesterday and went out and got a bottle of whiskey but unfortunately there was not a lot of insight that i got out of it so i am going back at it. i agree with you that it seems like air but i have absolutely no ides how it got in but i do find now that i am able to pump up the pedal to a decent level and it will hold , but let off wait a few seconds and hit the pedal it is back to very low.. i have got a new m.c. but am going to see what bleeding does. i already se that one bleeder valve is rusted badly so that could be another problem ...i will keep you posted thanks for the help sam

finally got back at it and did revisit the front wheels and did get a bit of air and the pedal was a bit better. i went to the rear and of course i found one of the bleader screws twisted off which had to from when the rear brakes were done about 3 years ago. got a new wheel cylinder and rebled the entire system and now have great pedal. i have still no idea how the air got into the system but the lady did tell me afterwards the the pedal had been a bit low ever sice the rear brakes were done. in any case it,s done and thank,s to all of you for your help. i had almost forgot to post my findings but then i remembered how crazy it made me to find a problem that fit my situation perfectly and find that the person never posted what he finally found sam