K 3500 1 Ton Pickup 4WD V8-379 6.2L DSL VIN J FI (1983)
Fig. 4 Fuel filter/water separator. 1984---87 C, K, R & V models
COMPONENTS
The fuel system consists of a tank, fuel pickup assembly, fuel filters, mechanical fuel pump, fuel line heater, and an injection pump, injector lines and
individual fuel injectors for each cylinder. On 1982---83 models, the fuel pickup incorporates a water in fuel detector, Fig. 1, primary and secondary fuel
filters are used, and a water drain siphon valve is included in the system, Fig. 2. On 1984---87 models, a single fuel filter assembly is used, which
includes the water in fuel sensor, water separator and drain, and the fuel heater, Figs. 3 and 4. In addition, 1984---87 models are equipped with a low
pressure switch which illuminates a warning lamp should the fuel filter become clogged.
SYSTEM OPERATION
1982---83
Fuel is drawn from the fuel tank through the primary fuel filter and by the camshaft driven mechanical fuel pump. It then flows through the fuel line
heater, which prevents fuel waxing, to the secondary fuel filter, which again strains contaminants from the fuel. The fuel is then directed to the high
pressure rotary vane type injection pump. The injection pump meters and pressurizes the fuel, then directs it through the equal length high pressure lines
to the injector nozzles.
Fig. 1 Water in fuel detector, strainer & pickup tube assembly. 1982---83 models
