THEORY OF OPERATION - CONTINUED
FUEL SYSTEM - CONTINUED
Fuel injection pump needs fuel for lubrication. Precision pump parts are easily damaged. Engine must not be
started until fuel injection pump is full of fuel. System must be primed when any part of system is drained of fuel.
These services and repairs require system priming:
Fuel filter changed
Fuel line removed
Fuel injection pump replaced
Primary Filter/Water Separator. Primary filter/water separator is located between fuel tank and priming pump. Pri-
mary filter/water separator has a rating of 10 microns.
Fuel Priming Pump. Pump is electronically operated to prime and transfer fuel to fuel system when engine is stopped.
In order to release air from system, orifice in cover of fuel filter is in inlet side of filter. It is located on top of primary
fuel filter base.
Secondary Fuel Filter. Secondary fuel filter is located after priming pump. Filter is always before fuel injection pump.
Filter has a rating of 2 microns.
Fuel Injection Pump.
N OT E
Refer to Schematic for the following fuel injection pump operations:
Generation of high pressure
Distribution and injection