Brake problem, need help

[alfajay]

So here it goes, the main brake line running to the rear of the truck blew. Dropped the tank, unbolted the fuel pump, took off the line, had a new one made out of stainless(14 1/2 feet long!) Just got done putting it on, everything else installed. All 4 wheels bled. Now when the truck is off, not running, there is plenty of back pressure on the pedal, feels as it should. I start it, the pedal loses 50% of the resistance. Its not at all like it was prior to the leak. There are no leaks, I am out of ideas. While I was waiting for the line to be installed I did the foil delete and that went fine. Is there a vaccuum line or something. I don't know **** about brake sys besides air is bad. There are brakes but I have to really step on it. It doesn't go to the floor, and if I pump the brakes rapidly it builds pressure, then it all goes away. I don't know what it could be. Any ideas would be awesome! I got like 8 hours in messing with this, and I need to be able to stop a trailer with 8k- 10k safely.

[mschn99]

fill the master cylender resevour.....bleed the master cylender...

You do this by having someone push the pedal hard, while you crack the lines on the master cylender....first do the one towards the cab about five times...then do the one towards the front bumper about five times. When you loosen the fitting about a quarter to half turn, air and fluid should come out....make sure your assistant doesnt let up on the pedal till the line is tight again.

Then do the RR wheel...bleed it about 10 times....then do the LR about 5 times....then do the RF about 6 times...and then do the LF about 4 times..

The key to all of this is making sure the assistant doesnt let up on the pedal after it goes to the floor till the line is closed.....

You shouldnt have to pump the brakes to bleed the master...but it wont hurt anything eitehr...you do have to pump them up to bleed the four calipers though...

If the soft pedal persists, you may have to have the dealer do an "abs bleed" which has to be done with a scan tool...

[alfajay]

OK, I didn't bleed the Master cylinder, just the 4 lines. Does it matter what kind of fluid? DOT 3, 4, 5? Its the same procedure with, apply brake pressure, loosen til pedal drops tighten, let pedal rise, apply pressure, loosen....right for both the master cyl. and the calipers.

IF i need the ABS bleed, about how long should it take, so I know if they are givin it to me, an hour or 4.

Thanks Marc I know see hope at the end of the tunnel w/o losing a big chunk of $

[mschn99]

where it sounds like the line was off for a while..im guessing you got air in the master cylender because most if not all of the fluid ran out....make sure to keep the master full during all of this.....and lets hope thats it...

Dot 3 fluid for all ford vehicles...

An ABS bleed with a manual bleed to follow...im guessing 1-1.5 hours of labor at a fair dealer....BUT they may want to diag it themselves...which could add an additional hour if they want to diag it. I honestly would want to do that myself so i didnt get burnt...unless the customer REALLY insisted that was all they wanted done...

the pedal your describing sounds EXACTLY like what air should do in a system..so now its just a matter of getting it out of where it is....

[alfajay]

Ok, yea, the line was off for 5 days cause there wasn't a dealer here that wanted to get the part/ told me I didn't want to know the cost. I had to find a place with tube, and someone compitent to bend all the bends. I really don't get why there needs to be 30 bends in it but oh well.

Thanks alot, I'm already telling my girlfriend to get her work clothes out tom. evening....she's going from pencil pusher to pedal pusher..LOL