help with my BRAKES

so i bolted on a new master cylinder from ABS with a booster but havent hooked up the vaccum line yet...(my original didnt have it)..also new calipers on new rotors up front and i did the explorer conversion in the rear also with new rotors and calipers.\
i bled the entire system and were getting a good amount of fluid out of each caliper but the pedal is still soft..no leaks though. i also have a summit adjustable proportioning valve but that shouldnt be causing the problem. i just cant figure out why my pedal is so soft????

 

Did you replace the rubber hoses? Old hoses will bolloon and give a soft pedal.

 

Are your bleeders all at the up most part of the calipers? May be on the wrong side of car.

 

Bleed them some more!
Just what I had to do, bleed mine the day after the first time and all was good.

 

calipers are on the correct way,,,hoses are new,, just gona take out the mc, bench bleed it again and do it all over again.. i may have some air trapped somewhere

 

The frist thing you need to due is hook up the vaccum line . Then see how the pedal feels

 

I agree w/ Mavdog71 - Hook up the vac line and try agn. That's why it's called a vaccum booster.

 

Is your master cylinder designed to be used with 4 wheel disc?

I would also hook up the booster and then test it.

 

so i should hook up the vaccum line and bleed the entire system with the engine running? not understanding why this would matter but then again im not a mechanic. anybody else have one of these abs setups?

 

I think they are just saying, hook up vacuum and see how it works. Like if your car sits long and loses all vacuum, when you hit brakes they sorta suck till you start engine up.

I've heard of new bleeding machines for ABS. Suppose to cycle the ABS while bleeding to get all air out of controls/valves. May want to check into that after you hook up vacuum hose.

 

no, you can bleed without the engine running.

Start at the farthest point, the passenger rear. Have a buddy press and hold the pedal. Open the bleeder, then close when fluid stops running out. Have him slowly release the pedal. Repeat. You might have to do this 10-12 times on the farthest run. Keep bleeding until you get 2-3 bleeds with no air bubbles. Repeat for the drivers rear, then passenger front and finally drivers front. Of course being sure not to run the reservoir dry in the process.

Then, start up the car and feel your pedal.

 

True, some Anti-lock brake systems require special bleeding procedures. But in this case, I think he means the company ABS.

http://www.abspowerbrake.com/

 

Thanks! I was thinking on the one post someone had of the Mustang abs he put on or something like that. My bad,,,

 

Do you have a pair of residual pressure valves in the lines to the right/left rear wheel??? 4 wheel disc setups need em to achieve a high pedal with low braking effort. If you are useing an ABS company M/C it may not have a residual valve built into it. If you are useing a M/C from a car that had ABS...It most certainly wont have built in residual valves. You need 2psi valves for the rear wheels.One for each rear wheel. If you are useing an abs system from a newer car (thats some serious re-engineering) You will have to follow the manufacturers bleeding proceedure to bleed em properly...You will also need some sort of scan tool to communicate with the ABS computer. You dont have to have vacuum on the booster to properly bleed the brakes but... Brake pedal feel will be different with vacuum on the booster than it is without. Good luck!!!