Please let us know what you figure out

 

The Brake Pressure Differential (aka proportioning) Valve also needs to be bled. This may be the root of the problem if it hasn't been.

 

Yes, I actually bought the $8 rebuild kit just haven't had time to do it. The backing plates I changed did nothing to help the problem so the proportioning valve is likely the issue because everything else has been done. Will try to get that done next week. Will let you know how it goes. Thanks for your help.

 

Have you checked to see if the Master Cylinder is coming all the way back to the pedal/push rod having free play after the pedal is released. Thinking in most cases there should be about 1/8" free movement of the push rod before it contacts the piston in the Master Cylinder. Just pushing the pedal, Slightly, with your hand, you should detect that free movement before the resistance when push rod makes contact. Cap

 

Ok will try that also, Thank You.

 

Not sure on your 71 F-100, but bigger trucks like F-600-700, I believe the bolt thru the push rod eye is eccentric and if you loosen the nut holding the bolt to the the pedal arm you rotate the bolt which would move the push rod fore or aft. Also there may be a rubber bumper the pedal arm will return against. The rubber bumper bracket, may be adjustable by a slot, for either adjusting how far the pedal comes back to rest or adjust pedal height. Cap

 

Finally got back to work on the brake situation, I rebuilt the (proportioning valve) but that didn't help. So I changed the master cylinder and all is good. Thanks for all the help and tips.

 

A little food for thought maybe, but that spring installation looks different than any brake set-up I have ever seen. Should there not be springs going from brake shoe to brake shoe?

 

Look correct to me

 

Philthytoo, Yes there are many set ups with just a common spring between the two shoes. Usually with Manually Adjusted brakes. The set up pictured is for Self Adjusting Brakes. Another note to mention is that a lot, if not all, Self Adjusting Brakes only adjust when applied, backing up. Cap.

 

crazy ? but have you done brakes on american cars and trucks with self adjusting brakes , springs between the shoes went out a long time ago like maybe 70 + or - years ago.