GENERAL SERVICE INFORMATIONTNV IDI Service Manual 4-7Function of Major Engine ComponentsFuel TankThe fuel tank is a reservoir that holds diesel fuel. When fuel leavesthe fuel tank it goes to the fuel filter / water separator. Next, fuel ispumped to the fuel filter by the fuel pump. Next the fuel goes to thefuel injection pump. Since fuel is used to keep the fuel injectionpump cool and lubricated, more fuel than necessary enters theinjection pump. When the injection pump pressure reaches a presetvalue, a relief valve allows excess fuel to be returned back to thefuel tank. The fuel tank is a required engine component.Mechanical Fuel PumpThe mechanical fuel pump is a diaphragm type of pump and isinstalled on the fuel injection pump body. The mechanical fuelpump is standard equipment on some engine models and is drivenby a cam on the camshaft of the fuel injection pump. Themechanical fuel pump is not installed on the fuel injection pump ifthe electric fuel pump is installed.Side and Top Filler Port (EngineOil)You can fill the crankcase with engine oil from either the side ortop filler port depending upon which one is most convenient.Starter MotorThe starter motor is powered by the battery. When you turn the keyswitch in the operator’s console to the START position, the startermotor engages with the ring gear installed on the flywheel andstarts the flywheel in motion.Component Function
