Fuel Delivery and Air Induction: Description and Operation

Purpose:
The 6.5L turbo diesel fuel injection system is designed to deliver a metered amount of fuel to each cylinder at specified time intervals.

Operation:
The 6.5L turbo diesel engine fuel system is composed of the following:

- Fuel Tank
- Mechanical lift pump
- Fuel filter with water sensor and heater
- Injection distributor pump
- High pressure lines
- Fuel injection nozzles

Fuel is drawn from the fuel tank by the mechanical lift pump which is located on the right side of the engine. Fuel is then pumped through the filter/water separator. The filter/water separator is located on the cowl. The fuel is then transferred to the injection pump.

The injection pump is mounted on top of the engine under the intake manifold. the pump is driven by the camshaft through two gears, one attached to the front of the camshaft and the other attached tot the end of the pump shaft. these gears are the same size and have the same number of teeth; therefore, the injection pump shaft turns at the same speed as the camshaft.

The injection pump is a high pressure rotary type pump that meters, pressurizes, and distributes fuel to the eight injector nozzles. the eight high pressure lines supplying the injectors are all the length although their shape may be different. The equal length lines prevent timing differences between cylinders. Injection lines should not be bent to ease removal.