4-2
Fuel/Lubrication/
Cooling
NOTE: Some photographs and illustrations used
in this section are used for clarity purposes only
and are not designed to depict actual conditions.
NOTE: Critical torque specifications are located
in Section 1.
SPECIAL TOOLS
A number of special tools must be available to the
technician when performing service proceedures in
this section.
NOTE: Special tools are available from the Arctic
Cat Service Parts Department.
Diesel Fuel
Injection System
The diesel engine in this Arctic Cat ATV is a “com-
pression ignition” engine. Extremely high pressure in
the combustion chamber raises air temperature high
enough to cause ignition of the fuel upon injection into
the combustion chamber. No spark is present or
required for ignition.
In this style of engine, diesel fuel is drawn from the
fuel tank by a low pressure lift pump. From the lift
pump, fuel is pumped through the fuel filter/fuel
shut-off and delivered to the fuel rail. Low pressure
fuel at 0.42-0.56 kg-cm
2
(6-8 psi) flows to the unit
injectors (high pressure fuel pump/fuel injector) where
the fuel pump, driven by a special lobe on the cam-
shaft, increases the fuel pressure to 143-153 kg-cm
2
(2030-2175 psi). At this point, the fuel is atomized by
the fuel injector nozzle as it enters the combustion
chamber.
Fuel in excess of the amount required for any particu-
lar power setting is directed back into the fuel return
side of the fuel rail and routed back to the fuel filter
head where it either recirculates or is returned to the
fuel tank via the fuel return hose.
Fuel flow is shut off when the ignition switch is turned
to the OFF position. A fuel solenoid valve is located
on the fuel filter head and opens the valve whenever a
12 DC volt current is applied to the solenoid.
Lift Pump
REMOVING
1. Remove the banjo-fitting bolts securing the fuel
hoses to the lift pump; then remove the two nuts
securing the lift pump to the cylinder head.
Account for four crush washers, an O-ring, and
two flat washers.
DE078B
DE309A
2. While holding pressure against the lift pump push
rod, rotate the engine until the push rod is fully
retracted.
NOTE: If pressure is not applied to the push rod
while rotating the engine, the push rod may
become dislodged from the eccentric ring requir-
ing valve cover removal to relocate.
INSTALLING
1. Using a new O-ring, place the fuel pump onto the
cylinder head and secure with the existing hard-
ware. Tighten the nuts alternately until the fuel
pump is seated against the head; then tighten
securely.
Description
p/n
Tachomenter
0644-275
Oil Pressure Test Kit
0644-495
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FOR ARCTIC CAT ATV DISCOUNT PARTS CALL 606-678-9623 OR 606-561-4983
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