j.c.whitney
Well-known member
Old school Champion Porta-Champ 1 cylinder homeowner model, no owners manual. Compressor starts and tank fills normally, motor shuts off at preset pressure limit. When air is used and pressure drops it tries to restart, after about 1/8 turn the motor stalls and hums. Turned flywheel by hand, there seems to be considerable pressure on the piston, does this type compressor have an unloader valve on the cylinder head or somewhere else? Tag on crankcase says it is a model B1 pump. Motor start capacitor checks good. Motor itself has some endplay on the shaft; my hope is that it has not shot craps. Is there a 1-way valve in the line between the pump and the tank to keep pressure off the piston when the tank is pressurized? Any help appreciated.