The Stovebolt Site Forums The Shop Area Engine Shop '42 vacumn brake ??

This is for the Hydro-booster? Big line off the intake manifold goes to a check-valve on firewall, then down to booster using some metal maybe following the frame and x-overs to get to it. There is a small "breather" in cab rear corner or behind end of seat. You can sometimes hear a hiss or something when letting off the brake pedal. OR, some COE's or GMC's have the breather on the firewalls. All these hoses may "rot" so check them. They also have tees to the rear-end if you have a 2spd unit. Most do! Lots of times the metal tubes will rust thru also and cause leaks, especially at clamps holding it to frame.