48 I now have about a 1/3 of the pedal weather I pump it or not. If I push on the pedal with my hand it will go to the down and return by itself. when I start the engine for the vacuum and push the pedal by hand or foot it will return not the best but it will return. when I put the truck in gear forward or reverse and start rolling and apply the brakes the brakes go down but do not return with out me physically using my hand or foot to return the pedal all the way back up.

Big I agree never seen or heard of a pv do something like that

Beltfed I bought the booster and master as a unit, suppose to come from the manuf. adjusted and it was cheaper then buying the 2 separate units and I didn't want to mess around trying to adjust them

it almost feels like it is binding up on some thing when I am rolling and apply the brakes. I've never had any thing like this happen before that I could not figure out but this has got me stumped

1938 Gmc 1/2 ton