The diesel fuel system (see Figure 4-1) consists of the following components:
• Low Pressure: Fuel tank, fuel (lift) pump, fuel filter or filters, fuel lines.
A. Low Pressure Fuel Delivery System. The system consists of:
• Tank filter sock.
• Mechanical lift pump.
• 1982-83 Primary fuel filter.
• Fuel Line Heater.
• 1982-83 Secondary fuel filter.
• 1983 G-P Truck Secondary fuel filter.
• 1984 Model 80 fuel filter (1984).
B. High Pressure Fuel Delivery System. The system consists of:
• Fuel injection pump.
• High pressure lines.
• Nozzles.
Fuel is pulled from the fuel tank by the Mechanical pump which is located on the right side of the engine. It is driven by an eccentric lobe on the camshaft through a push rod. Fuel is pulled through the primary filter (1982-83 only), by the Mechanical pump. Fuel is then pumped through the secondary or model 80 filter mounted on the inlet manifold. Both filters remove foreign material which could damage the injection pump or clog the injector nozzle. From the filter, the fuel is pumped to the injection pump.
