No brakes

[tuna2004]

Need some help, I blew a rear brake lin on my '95 F-250 replaced the line, still had soft brakes ,replaced the master still had soft brakes changed the back cylinders same result, changes the master again same result, put a new vacuum pump new hose and new booster same result does any one have any ideas what I could be doning wrong?

[Brian]

welcome to the forum!!
maybe theres still air in the line. what caused the line to break?

[tuna2004]

Rusted through but I replaced all of the brake line incuding the rubber hoses.

[pipelayerjdh]

Sounds like air to me. Are the rear shoes adjusted properly?

[owtcast]

It has to be air or the new rubber line is "sub par" and expanding when you hit the brakes. You sure all the cylinders have the same size pistons/volume?

[fordnut85]

Sounds like air to me, start with the wheel furthest from the master and work your way closer. Try and pump all the old fluid out of the sytem and pump new in.

[WILLIAM LORCH]

Wow this is de ja vouix, Ok if youhave 2 folks the ole pump hold it OK pump routien. Start with right rear,do it untill you get get clear new fluid, than go to left rear than righ front than left front. If no help at this point jack up rear and adjust the rear drum breaks untill you can just hear them tick at the shoes and it still turns easly. that should do it.. If not check for a seep in a line or around a fitting , than IF that fails look at the rubber flex lines on hte front wheels and see if they are expanding while your break pumper is applying break pressure .. That is about how to trouble shoot the whole system ??? All new shoes and Pads??? 2 thin roters or worn drums wouldent act like what you are discribing...be sure the pistons are returning on the front calapers and not dragging a front pad..that would make 4 harder breaks tho.. It would not b the vacume boost as that is what it is : a BOOST for hte break's to apply more pressure than you can with just the foot pedal. hope that helps you i am one who goes for the master cylender LAST wen all else fails and thye dont usulay do no cure anything......... Best of luck with your problem.<<<<<<<<<<BILL>>>>>>>>>>>

[alfajay]

I had a line rust out on me and had the same prob about 3 weeks ago, I had to bleed about a 3qts of brake fluid through the sys starting at MC then the rear calipers to the front. 2 people are really the only way to do it. If I remember, I was told to start with the MC pump the pedal 10x starting at the back line, then the front line. Then the rear pass. side 10x, rear dr. 6x, Front pass 6x, front dr. 4x. I doubled it so there was no way and I haven't had a problem, I was also told my someoen it can hellp if you start the truck and let it run while you do this....mechanic said it helped build better pressure.
Good luck, I know mine was a pain in the @$$! I need a custom line bent tho

[tuna2004]

Thanks eveybody for the help. I finally found the problem,: the plastic resivor for the master cyln had a small crack on the passagener side right at the seam. So after replacing the resivor we now have brakes!

[WILLIAM LORCH]

Great!!! Love to hear a good fix.. Seep huh.!!!!! That was my prob with a rusted break line i never saw the rust spot where it was broken through.... Bill