is the pedal supposed be rock hard with air in the system? when I got it the front left was caped
so I replaced that hose and hooked it back up because my right caliper started to lock tight, now both front are locking tight, when I first hooked it back up the pedal went half way down for the first time and wonted to stay there so I pull the pedal back up, the next time I pushed it, it went back hard. it has power brakes, I cleaned out the lines and replaced the master cylinder. the calipers are still good because they don't leak and I put them in a vice and was able to compress them, set them a little loss in the vice and put air to them and they travel free and will clamp(I did use a piece of wood for the test )
1971 F100 sport special 390 fe
1993 F250 4X4 ext-cab 6.9 idi
mouse wrote:is the pedal supposed be rock hard with air in the system? when I got it the front left was caped
That would make it pull to the right and be kinda scary to drive.
When you replaced the master cylinder did you get a Disc/Drum type or a Drum/Drum one? With the P/B is the rod adjusted where you have just a little free play in the pedal before it applies the brakes...
Also, you say the fronts know lock up, are you saying that when you hit the brakes they lock up and wont release or are they just really grabby (touch the brakes and they lock up but when you let off they are ok)?
Shayne
I'm not "Brand Loyal" Ford-Chevy-Dodge-Toyota I have them all, one even cross mixed...
If it Looks good and Works good then it's ok by me. Everything has its issues from time to time...
Not to hijack, but that reminds me of two of the stupidest things I've ever personally seen automobile-wise.
1) Guy I knew years ago bought a 65 GMC pickup. Not a beater at all, looked nice inside and out and ran good. Didn't stop worth a darn. PO had removed all the guts from the from the front brakes, shoes, wheel cylinders, hardware. Put the drums back on and kinked the rubber hoses over and clamped them to stay kinked.
2) Many, many moons ago in high school auto shop a kid bought an old hippie VW bus. Didn't hardly stop at all. We pulled the drums and discovered that the PO apparently didn't like the metal to metal sound that his shoes were giving as they ripped the snot out of the drums so he packed the drums in grease to silence them.
Some people don't take their lives very seriously.....
AS to the problem you're having, I've heard bad hoses can cause that, they collapse internally and allow the pressure into the slave cylinders/calipers, but do not release fully. You changed that one hose, you might want to change the other side and the rear one as well.
when I bought it pulled to the right slightly all the time and a little more when I hit the brakes, but it would stop on a dime. I put air through the lines and do you think I can power the pistons out of the caliper with out damaging the seals because the rubber boots are in superb condition from what I saw in my bench test. got the Disc/Drum type master and I make sure I state that. the calipers lock tight when I hit the brakes but when bleeding I got a lot of pressure and bled air once
1971 F100 sport special 390 fe
1993 F250 4X4 ext-cab 6.9 idi
No problem with using air on them, you can’t get enough air pressure (normally) to hurt anythng, as the brake fluid pressure is upwards of 1200psi for disc brakes…
Do check the other front brake hose as ToughOldFord said above, but if both fronts are now locking up I would suspect something with the master cylinder, or possibly the proportioning valve… Also, double check that the line for the front brakes is connected to the correct port on the master cylinder and proportioning valve. The previous owner might have messed/crossed these up…
Shayne
I'm not "Brand Loyal" Ford-Chevy-Dodge-Toyota I have them all, one even cross mixed...
If it Looks good and Works good then it's ok by me. Everything has its issues from time to time...
another thing I can't compress the calipers real well wile there hooked up but if loosen a line they will, air went through line with out a problem and all the lines can hook up one way, to split the line for the front theres a T not a valve
1971 F100 sport special 390 fe
1993 F250 4X4 ext-cab 6.9 idi
I had a problem with my brake pedal in my hi boy and when I applied the brakes, the pedal wouldn't return. I replaced the master cylinder and booster and it took care of the problem.
As for the other problems, the previous post are a great place to start.
with the caliper on the right side unhooked. can you push on the brakes and get fluisd to come out fo the right side line? if you can the caliper is bad or has dirt in it. and need replaced or rebuilt.
That would make it pull to the right and be kinda scary to drive. 
