What's wrong with my brakes?

[noley99]

Sorry if this has been discussed before.

Just finished installing all new brake lines, wheel cylinders, shoes, converted the system to power disc/drum with a new proportion/distribution valve. The problem is I have a very soft pedal when the truck is off and no pedal when the truck is running. That leads me to believe that the booster is good but something else is wrong. I have bled the lines by cracking loose the right rear bleeder valve and letting it drain for about an hour then going from corner to corner bleeding the lines.

What could it be?

[tomrooster]

Did you bench bleed the master cyl. before installing it. Might be the problem. Tom


Here's one

http://autorepair.about.com/od/fixityou ... -bleed.htm

[BigWindowFord]

That's what I think too. I changed a master cylinder on an O/T car and ignored the bench bleeding. Same symptoms. The air will eventually either go out to the reservoir or arrive at a bleeder screw but on the O/T car it took thousands of miles.
Notice how I do not care driving around on crappy brakes - pathetic really

[banjopicker66]

x3 on the bench bleeding.

[noley99]

No, didn't bench bleed. I will give it a try and see what happens.

Thanks!

[noley99]

Now I'm stumped I've taken the MC off and bled it. Reinstalled it and bled the brakes but still have no pedal to speak of. Checked to see if the rod was long enough to engage it and it is. I know the booster is working fine so could it be the MC is bad?

[noley99]

Feeling a little better now that I have some pedal. Found that the shaft coming out of the booster into the MC was adjustable ( forgive my ignorance) with a small bolt threaded into the end of the shaft. Adjusted it all the way out and think I still need more as I don't have very much pressure. What do you guys think?

[noley99]

Worked it out. Added a longer bolt to the end of the shaft out of the booster. Stops on a dime and gives nine cents change!

[TXSlick]

You should adjust that rod to give about 0.010" clearance, if you want a dimension. But if it works and the brakes don't drag, you got it right. Too long can be a problem also.

[ICEMAN6166]

You should adjust that rod to give about 0.010" clearance, if you want a dimension. But if it works and the brakes don't drag, you got it right. Too long can be a problem also.

yes, some clearance is needed as brakes build up heat and will stick.

school of hard knocks, lesson 127.