all 4 brakes locking up while driving! please help!!!!

[dwnshfter]

I was driving down the road as normal and my brakes started to start dragging, then another mile all four of them locked up completely? The pedal got very, very stiff and I could hardly move it off the road. my booster was filling up with fluid about 2 weeks ago and i got a new one from the junkyard and replaced it. it has worked for about a week now and now i am having this issue. all 4 brakes lock up and i cant even push the pedal down. so do i need to bite the bullet and buy a new one from the part store for $150 or what? i didnt grease the master cylinder before i put the new master on. also i replaced the master, but it was a used one from the junkyard also.....

[hai1206vn]

Same problem after my z32 brake swap with junkyard s14 booster. Bought a reman'ed booster from ebay for $75 and all was good.

If you pull one from an old car and see paint bubbling off the booster near the front hole (where you mount the master), don't buy it.

If your master is leaking, get a new one before destroying your new booster.

[dwnshfter]

booster adn master were good, it was the check valve between the booster and the engine. after shutdown it would slam it shut and i would lock up all the brakes.