2007 Arctic Cat 700 Diesel ATV Service Manual, Page 104Get this manual
Diesel Fuel Injection System The diesel engine in this Arctic Cat ATV is "compression ignition" engineExtremely high pressure in the combustion chamber raises air temperature high enough to cause ignition of the fuel upon injection into the combustion chamberNo spark is present or required for ignitionIn this style of engine, diesel fuel is drawn from the fuel tank by low pressure lift pumpFrom the lift pump, fuel is pumped through the fuel filterfuel shut-off and delivered to the fuel railLow pressure fuel at 0.42-0.56 kg-cm2 (6-8 psi) flows to the unit injectors (high pressure fuel pumpfuel injector) where the fuel pump, driven by special lobe on the camshaft, increases the fuel pressure to 143-153 kg-cm2 (2030-2175 psi)At this point, the fuel is atomized by the fuel injector nozzle as it enters the combustion chamberFuel in excess of the amount required for any particular 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 hoseFuel flow is shut off when the ignition switch is turned to the OFF positionA fuel solenoid valve is located on the fuel filter head and opens the valve whenever 12 DC volt current is applied to the solenoidDE309A