SHAFT- 4431048 - Caterpillar

Engine Information
The Caterpillar engine has the following characteristics:
Four stroke cycle
Direct fuel injection
Hydraulically actuated electronic unit injection
Turbocharging
Radiator cooledEngine Specifications
Table 1
C9 Engine Specifications
Arrangement and Cylinders In-Line 6 cylinder
Bore 112 mm (4.4 inch)
Stroke 149 mm (5.9 inch)
Aspiration Turbocharged Aftercooled
Displacement 8.8 L (537 in3)
Firing Order 1-5-3-6-2-4
Rotation (flywheel end) Counterclockwise
Compression Ratio 16.1:1 Note: The front end of the engine is opposite the flywheel end of the engine. The left side and the right side of the engine are determined from the flywheel end. The number 1 cylinder is the front cylinder.
Illustration 1 g00920494
Cylinder and valve location
(A) Exhaust valve
(B) Inlet valve Electronic Engine Features
These Caterpillar Engines are designed for electronic controls. These engines have an integral on board computer that is called an Electronic Control Module (ECM). The ECM monitors current engine conditions and power requirements. The optimum engine response is calculated and instructions are sent to the engine control systems. The systems respond and the engine responds accordingly. Total engine control is realized through the control of the fuel system and the engine speed/timing system. The electronic engine control system provides the following features:
Engine speed governing
Injection timing control
Automatic air/fuel ratio control
Torque rise shaping
Engine monitoring and protectionThe ECM provides the electronic governing of fuel delivery in order to dictate the following engine controls: engine speed setpoint, engine timing accuracy, air/fuel ratio control and torque rise fuel setting.Electronically controlled, mechanically actuated unit injectors combine the pumping, electronic fuel metering (duration and timing), and injecting elements of the fuel system into a single unit. Each cylinder has an independent unit injector.Fuel metering is controlled by an electrical signal that is sent to the injector solenoid from the ECM. High fuel injection pressures are produced by the unit injector pump. High injection pressures and accurate fuel metering ensure good fuel atomization and thorough combustion. This state-of-the-art technology provides the engine with the following benefits: reduced fuel consumption, controlled smoke emissions and electronically controlled acceleration ramp rates.The engine timing control and speed control are provided by the ECM. The speed/timing circuit consists of two speed/timing sensors. During engine cranking, the ECM uses the timing signal from the secondary speed/timing sensor. The timing signal from the primary speed/timing sensor is used by the ECM while the engine speed is greater than cranking speed. Utilizing two sensors for this circuit has several advantages. Each of the speed/timing sensors is treated as a discrete component by the ECM. If the signal from one of the sensors becomes suspect the ECM will use the signal from the other sensor in order to keep the engine operational.Injection duration is also managed by the ECM. The duration of the fuel injection cycle determines the engine speed. The placement of the injection cycle in relation to the crankshaft position will determine the timing advance. The speed/timing circuit provides information to the fuel cooled ECM for detection of crankshaft position and engine speed. This information is utilized by the ECM in order to control desired engine speed and engine timing.The ECM changes injection timing