Hello all I have recently bought a 1970 GMC with a hiab knuckle but I can't make the outrigges work maybe I'm missing something they don't appear to have any line going to the outrigger it only has 3 Handel's on controls none for outriggers they do have a screw valve on top and appears you wind valve out to increase there is a pipe plug on side of tube what do I do hiab is no help at all I have no book with the truck either
Turn handle hard one way (up ,hold ,down) Pull any leaver outrigger will operate. Best to pull a leaver that will bottom out a cylinder.