34567-1140 Tohatsu PLATE, STEERING HANDLE

General Description
Right Side View
(1) Transformer. (2) Governor actuator. (3) Deceleration Fuel Cutoff Valve (DFCV). (4) Air/Fuel control. (5) Carburetor. (6) Deceleration Fuel Cutoff Solenoid (DFCS). (7) DIS magnetic pick-up sensor. (8) Governor speed magnetic pick-up sensor. (9) Pre-catalyst. (10) Oxygen sensor.
Left Side View
(2) Governor actuator. (3) Deceleration Fuel Cutoff (DFCV). (4) Air/Fuel control. (5) Carburetor. (6) Deceleration Fuel Cutoff Solenoid (DFCS). (11) Caterpillar Interface Module (CIM). (12) Air temperature sensor. (13) Manifold air pressure sensor.The G3306 Truck Engines are in-line six cylinder arrangements, with a firing order of 1, 5, 3, 6, 2, and 4. The engine rotation is counterclockwise as viewed from the flywheel. The engines are turbocharged and air-to-air aftercooled. The G3306 Truck Engines have a bore size of 120.7 mm (4.75 in) and a stroke of 152.4 mm (6.00 in).Engine Control System
The G3306 Truck Engines has been designed with an electronically controlled ignition and governor systems in combination with an electronic air fuel ratio control module (ECM). The ignition system controls the timing of the transformers which send a spark (impulse) across the electrodes of the spark plug. The governor system controls engine speed by controlling the amount of flow into the combustion chamber with the use of a governor actuator connected to a throttle plate under the carburater. The ECM uses the following inputs: * Manifold Air Pressure Sensor (MAPS)* Inlet Manifold Temperature Sensor (IMTS)* Throttle Position Sensor (TPS)* Oxygen SensorWith these measured parameters the ECM is capable of controlling the air/fuel mixture to provide the best engine performance at all engine speeds. The software maps are set to adjust the mixture flow into the carburetor based on temperature, pressure, the amount of oxygen in the exhaust gases, etc.Ignition System
Ignition System SchematicThe Digital Ignition System (DIS) is designed to replace the traditional magneto ignition system. The Digital Ignition System eliminates the magneto and other components that were subject to mechanical wear.The DIS system has no wearing parts and monitors engine operation and distributes power to the cylinder transformer. The DIS system releases stored energy in response to process signals from the speed sensor to provide precision timed sparks for maximum engine performance. The DIS system allows improved operation, economy and lower emission levels. The system consists of three basic groups: The DIS control module, ignition coils and sensors.Spark Plug Adapter
Spark Plug Adapter
(1) Adapter. (2) Seal. (3) Cylinder head.The spark plug adapter (1) is mounted on a bracket located on the top of the engine. Seal (2) stops any type of leakage between the adapter and the cylinder head. The adapter extends upward through a hole in the valve cover.Spark Plug And Ignition Transformer
Spark Plug And Transformer
(1) Transformer. (2) Wire assembly. (3) Rubber boot (part of wire assembly). (4) Spark plug.Transformer (1) is mounted on the valve cover. Wire assembly (2) is the high tension lead to ignite the spark plug (4). Rubber boot (3) is part of wire assembly (2). The boot forms a seal between the adapter and valve cover to keep dirt, water or other foreign material out of the adapter. The rubber boot (3) prevents crankcase vapors and oil from entering the adapter. Wire assembly should not be painted.
Both the wire assembly (2) and rubber boot (3) must be installed on all cylinders when running the engine. Failure to do this may allow a spark from the exposed wire assembly to ignite crankcase vapors. Engine damage could result.
Ignition Transformer
The ignition transformer causes an increase of the voltage. This is needed to send a spark (impulse) across the electrodes of the spark plugs. For good operation, the connections (terminals) must be clean and tight. The negative transformer terminals, with (-) mark, for each transformer are connected together and to ground. The wiring diagrams show how all wires are to be connected to the plug connection at the DIS.Governor System
Governor System SchematicThe governor control system provides precise engine speed control over a broad range of driving conditions. The control is programmed through a lap top computer. The control system has the following OEM features: transmission neutral contact, neutral fuel limit, door interlock contact, PTO contact, speed switch/throttle position switch output, idle validation contact, and transmission signal output.The governor control system is programmed with both minimum and maximum engine speed governor set points. The minimum governor set point controls both the speed of the engine and the position of the governor actuator under idle conditions when the throttle pedal is resting at its minimum position. The maximum governor set point controls engine speed and actuator position if the maximum speed set point is reached. Between these two set points, the position of the governor actuator is directly proportional to the position of the throttle pedal.Fuel System
Fuel, Air Inlet And Exhaust System With TurbochargerThe fuel system consists of a gas regulator(s), an idle enrichment line, a Deceleration Fuel Cutoff Valve (DFCV), and air/fuel control valve and a carburetor/throttle. In addition to components shown in the diagram, typical installations have an OEM supplied Gas Shut Off Valve (GSOV) in the supply line for the gas. The valve is electrically operated from the ECM or by oil pressure.The gas is supplied to thee gas regulators which regulate the flow of fuel through the DFCV to the air/fuel control valve. The air/fuel control valve supplies the correct amount of fuel to the carburetor based on an input signal from the ECM. The carburetor mixes the gas with inlet air and delivers it to the combustion chamber. The throttle body which is controlled by the governor actuator.The idle enrichment line is used to improve the low idle air fuel ratioo and startibility. The DFCV is an air operated valve that is used to shut-off the fuel supply during deceleration to save fuel and reduce exhaust emissions. When engine deceleration condition is recognized by the ECM, the Deceleration Fuel Cutoff Solenoid (DFCS) receives an input signal and provides air to the DFCV. The balance line maintains the correct differential pressure between the gas pressure regulator(s) and carburetor inlet.Gas Pressure Regulator
Regulator