Related Photo Galleries
All classic Mustang engines have positive-displacement oil pumps, also known as "G-rotor" pumps with a two-stage inner and outer rotor. The inner rotor is camshaft driven. The outer rotor rides on the inner rotor, with the two closing up and moving oil from the pan to the engine's oil galleys. Whenever you replace an oil pump or build an engine, pump cavities must be filled with SAE 30 weight oil or engine assembly lube to ensure pump priming for a healthy start up.