[Birdawg]

A month ago I put new rotors, pads, calipars and master cylinder on the jeep.... Worked great for the past month. Yesterday I noticed both front breaks dragging, the more revs I put on the engine to over come the breaks dragging the more they dragged. I unhooked and plugged the break booster's vacuum line. Of course the breaks are stiff with no vacuum assist but the breaks don't drag. It seems the break booster is appling the breaks on its own!!! Any one have this happen before??? I mean I've lost breaks before for one reason or another but never had a problem with too much breaks!! It seems to me that the vacuum is stuck on the master cylinder side of the booster's diaphram and not releiving??.. Does that sound right or am I way off?? Any way, my question is that Can the break booster be taken off and cleaned up,.. repaired or is time for a new one?? Hoping for a repair just dumped several hundred on engine work last week!!
Thanks
Peter

[CanukYJ]

Get one from a junkers or just install something similar to a blow off valve but reverse and splice it into the line so the booster will suck air in from that when it hits a certain pressure. I would just snag one from a junkers because the booster should be dissipating the extra vacuum on its own and it isn’t. Worst comes to worst and you wanna be cheap about it, put a small hole in the line and make it bigger and bigger until the pressure is just right.

[Birdawg]

Found the problem!! Turns out replacing the master cylinder is not just a mater of unbolting one and bolting another one on... I took the Master off to see what I could do with the booster and noticed the shaft coming out of the booster to go into the back of the master cyl. seemed to be longer than the recess in the master . I measured them and sure enough the shaft was 1/4 inch longer. It had a threaded bolt on the end of the shaft for adjustment so I screwed it in 1/4 inch and boxed it back up. Works great now. The longer shaft was applying the brakes a little all the time and not allowing any room to release the vacuum... Never noticed for the past month because my engine was sick and only breathing on 5 lungs... After I got all 6 cylinders going strong I had a lot more vacuum and that's when the break problem was realy noticable.
Thanks and Take Care
Peter