The crankshaft translates rotational motion to reciprocating motion in a compressor pump. A crankshaft has “journals”, where the connecting rods ride on. A crank can be damaged by running the pump too low on oil, or if the drive belt is too tight. Make sure the output shaft (where the pulley installs) is not warped, and if you hear knocking, stop the unit immediately and disassemble the pump. When conrods seize onto the crankshaft, the journals must be polished of all aluminum (or iron) deposits before new conrods are installed. If pitted deeply, the crankshaft must be replaced.
This item fits the following models:
1/4" x 50 Ft Noodle Air Hose with Coupler and Plug