The fuel system supplies fuel to the engine. The diesel fuel is pumped from an in-tank fuel pump through two filters to the
fuel transfer pump and into the fuel injection pump. The fuel leaves the fuel injection pump under pressure and enters the
injector nozzles where it is sprayed into the combustion chamber for burning. Extra fuel used for cooling the nozzles
returns to the tank for reuse
The fuel tank is a welded box of steel construction and is mounted under the cab on the right side. It has a drain plug, a
fuel level gage sending unit, and a submerged fuel pump.
IN-TANK FUEL PUMP
The in-tank pump is a submersible electric pump mounted in the fuel tank that delivers a steady flow of fuel to the injection
pump. It is also used for priming the fuel system.
Two spin-on cannister-type filters clean the fuel system. The primary filter is mounted on the right frame. It serves as a
water trap and protects the fuel system by filtering out large dirt particles and insoluble gums. The secondary filter is
mounted on the right side of the engine block and supplements the primary filter by removing any tiny particles that may
pass through first-stage filtering.
The fuel supply lines are rigid lines with a flexible hose between the filters that carry fuel from the tank to the fuel injector.
The fuel return lines are rigid lines connected by a flexible hose that carry extra fuel from the injector nozzles back to the
FUEL TRANSFER PUMP
The fuel transfer pump is mounted on the side of the fuel injection pump and is driven by the injection pump camshaft. It
sends fuel from the filters to the injection pump.
FUEL INJECTION PUMP
The injection pump is an in-line single action plunger-type unit mounted on the engine. It has an integral mechanical
flywheel-type governor and damper valve to regulate pump pulsation and pressure of fuel delivered to the injector nozzles.
Eight injector nozzles are mounted in the engine cylinder heads. They are the inward opening differential-needle type, and
direct the fuel under pressure from the injection pump into the engine combustion chambers in the form of a fine mist.