Fuel Delivery

Fuel is drawn through a filter sock on one end of the fuel pump and is forced out the opposite end. Two check valves are used. One relieves internal fuel pump pressure and regulates maximum fuel pressure output.

The other check valve, located near pump outlet, restricts fuel flow in either direction when pump is not running. Fuel not used by the engine is returned to the tank by a fuel return line.

Power to the fuel pump is supplied through the Automatic Shut-Down (ASD) relay of the SMEC. When the SMEC receives a signal from the distributor during engine cranking, it grounds ASD motor, closing ASD contacts. When contacts are closed, power is applied to fuel pump.

When distributor signal is lost, the SMEC opens the ASD motor, which cuts power supply to fuel pump. This prevents fuel flow should the vehicle be involved in an accident or if engine stalls.