Brakes on a 68

[reliabilty]

Any suggestings to possible cause of no brake pedal. I just bought the truck. It is a 68 F100 long wheel base. The guy i bought it from had just put disc brakes on the front. The master cylinder was leaking so we replaced it hoping it would help, it didn't. The brakes just don't seem to want to pump up.

[SteveC]

air in the system or a very small leak some were that is allowing air into the system

[QC]

Did you buy a disc brake m/cylinder?
Did you bench bled it before you installed it?

[Rusty67]

Always bench bleed a MC before installing. Any time you have a fiting it is a potential problem/leak. Did you bleed the brakes out after you installed the new MC ? Were you geting a good amount of fluid out of the calipers with every pump of the pedal ? Don't forget to bleed the rears too.

[fordman]

since you don't know the history of this truck you will want to start at the master cylinder and work towards the wheels. look fo rleaky areas. make sure to bench bleed the master cylinder. and bleed all of the brakes starting at the furthest wheel away fromt he master and work to the front and closest to the master last. make sure everything is bled and all of the air is out of the lines.

[reliabilty]

Excuse my ignorance...but exactly what is bench bleeding. The guy I bought the truck from put the MC on. I helped bleed the brakes, "pumping the pedal". Not sure how much fluid was coming out of the lines while bleeding,. He was sort of in charge of the job. Didn't really want to step on toes, if you know what I mean. He also changed the front brakes over to Disc. I didn't know it would call for a different MC for that. I took it to a shop today. I am having the mid shaft bearing replaced on the drive shaft and I ask them to see if they could tell why the brakes won't pump up properly. Thanks for the post guys!!!

[fordman]

when you get a new master cylinder you put it in a vise and pour fluid in it. then you use a rod to push the rear of the master in and out to pump the fluid through the master to make sure it has fluid into it. this saves time and gets air out of the master before hooking it to the brake lines on the truck. i guess you could bolt it ontot the truck and just pump the pedal to bench bleed it too. as long as you don't hook the lines up to it. but you need one of those one man bleeder things so you don't pump fluid all over the engine compartment.

[19FORD67]

Do you keep having to add fluid? It's leaking fluid if so. If not I'd say air in the line. Did the previous owner install a proportioning valve along with the new MC? From what I remember the Prop is mostly for hard/emergency braking, I wonder if a missing/faulty prop could cause squishy brakes.