3406E Generator Set Engines Caterpillar

• Four cycle

• Direct fuel injection

• Mechanically actuated electronic unit injection

• Turbocharged

• Air-to-air aftercooled

Electronic Engine Features

The Caterpillar 3456 Generator Set Engine is designed for electronic controls. The integral on board computer controls the operation of the engine. Current operating conditions are monitored. The Electronic Control Module (ECM) controls the response of the engine to these conditions and to the demands of the operator. These conditions and operator demands determine the precise control of fuel injection by the ECM. The electronic engine control system provides the following features:

• Engine and auxiliary monitoring

• Engine speed governing

• Automatic air/fuel ratio control

• Torque rise shaping

• Injection timing control

• System diagnostics

An electronic governor controls the output of the unit injection pump. This maintains the desired rpm.

Electronically controlled, mechanically actuated unit injectors combine the pumping, the electronic fuel metering (duration and timing) and injecting elements. This produces very high injection pressures.

Each cylinder has one individual unit injection pump. Each unit injection pump meters the fuel. The unit injection pump also pumps the fuel under very high pressure to each cylinder. High injection pressures will help to reduce fuel consumption. The high injection pressures also help to reduce emissions. The use of this type of unit fuel injector provides total electronic control of injection timing. The injection timing varies with engine operating conditions. This optimizes the engine's performance for the following items: starting, emissions, noise and fuel consumption.

These engines are equipped with a vandalism protection arrangement. The vandalism protection arrangement prevents any tampering of the fuel ratio control setting. This is required by emissions regulations. Standard bolts have been replaced by tamper resistant bolts.

For more information on electronic engine features, refer to the Operation and Maintenance Manual, "Engine Features and Controls" topic (Operation Section).

Engine Cooling and Lubrication

The cooling system consists of the following components:

• Centrifugal pump that is driven by gears

• Water temperature regulators which regulate the engine coolant temperature

• Oil cooler

The engine lubricating oil, that is supplied by a gear type pump, is cooled. The engine lubricating oil is also filtered. Bypass valves provide unrestricted flow of lubrication oil to the engine components during the following conditions:

• High oil viscosity

• Plugged oil cooler or plugged oil filter elements (paper cartridge)

Engine Specifications

Note: The front end of the engine is opposite the flywheel end of the engine. The left and the right sides of the engine are determined from the flywheel end. The number 1 cylinder is the front cylinder.

Illustration 1	g00284836
Cylinder and valve locations (A) Inlet valves (B) Exhaust valves