The 3056 Marine engine is available as a turbocharged aftercooled arrangement or as a naturally aspirated arrangement.
Turbocharged engines are equipped with an air/fuel ratio control that is located on the governor. The air/fuel ratio control restricts the fuel rack movement. Only the proper amount of fuel is allowed to be injected into the cylinders during acceleration. The control of the air/fuel ratio minimizes exhaust smoke.
Emissions certified engines are equipped with a protection cover group that discourages tampering with the setting for the air/fuel ratio control. Standard bolts have been replaced by tamperproof bolts. This is required by regulations for emissions. Changing the air/fuel ratio control could cause the engine to exceed standards for emissions.
The engines are powered with direct fuel injection. A hydramechanical governor controls the fuel injection pump output in order to maintain the engine speed that is selected by the operator.
Fuel is metered and pumped by the fuel injection pump under high pressure to the fuel injection nozzles (one per cylinder). The automatic timing advance provides the best fuel injection timing over the full range of engine speed.
The cooling system consists of the following components:
- A centrifugal pump that is driven by a gear
- One water temperature regulator which regulates the engine coolant temperature
- Heat exchanger for the closed water circuit
- Marine gear oil cooler
- Auxiliary water pump
- The turbocharged aftercooled 3056 Marine engine has a strainer for the auxiliary water pump.
- Expansion tank
The engine lubricating oil is supplied by a gear type pump. The engine lubricating oil is cooled and filtered. Bypass valves provide unrestricted flow of lubrication oil to the engine parts when oil viscosity is high. Bypass valves can also provide unrestricted flow of lubrication oil to the engine parts if the oil cooler should become plugged or if the oil filter element should become plugged.
Engine efficiency, efficiency of emission controls, and engine performance depend on adherence to proper operation and maintenance recommendations. Engine performance and efficiency also depend on the use of recommended fuels, lubrication oils, and coolants. Refer to the Operation and Maintenance Manual, "Maintenance Interval Schedule" for more information on maintenance items.
Engine Specifications
Note: The front end of the engine is opposite the flywheel end of the engine. The left and the right side of the engine are determined from the flywheel end. The No. 1 cylinder is the front cylinder.
3054 Marine Engine
 | |
| Illustration 1 | g00774292 |
(A) Exhaust valves (B) Inlet valves (C) Rear of the engine (D) Front of the engine | |
| 3054 Marine Engine Specifications | |
| Operating Range (rpm) | 1500 to 2400 (1) |
| Number of Cylinders | 4 In-Line |
| Bore | 100.00 mm (3.937 inch) |
| Stroke | 127.00 mm (5.00 inch) |
| Aspiration | T (2) |
| Compression ratio | 17.25:1 |
| Displacement | 4.00 L (243 in3) |
| Firing Order | 1-3-4-2 |
| Rotation that is viewed from the flywheel | Counterclockwise |
| Valve Lash Setting (Inlet) | 0.20 mm (0.008 inch) |
| Valve Lash Setting (Exhaust) | 0.45 mm (0.018 inch) |
| ( 1 ) | The operating rpm is dependent on the engine rating and the application. |
| ( 2 ) | Turbocharged |
3054B Marine Engine
| | |
| Illustration 2 | g00774292 |
(A) Exhaust valves (B) Inlet valves (C) Rear of the engine (D) Front of the engine | |
| 3054B Marine Engine Specifications | |
| Operating Range (rpm) | 1500 to 2400 (1) |
| Number of Cylinders | 4 In-Line |
| Bore | 103.00 mm (4.055 inch) |
| Stroke | 127.00 mm (5.00 inch) |
| Aspiration | NA (3) |
| Compression ratio | 18.5:1 |
| Displacement | 4.23 L (258 in3) |
| Firing Order | 1-3-4-2 |
| Rotation that is viewed from the flywheel | Counterclockwise |
| Valve Lash Setting (Inlet) | 0.20 mm (0.008 inch) |
| Valve Lash Setting (Exhaust) | 0.45 mm (0.018 inch) |
| ( 1 ) | The operating rpm is dependent on the engine rating and the application. |
| ( 3 ) | Naturally aspirated |
3056 Marine Engine
 | |
| Illustration 3 | g00774394 |
(A) Exhaust valves (B) Inlet valves (C) Rear of the engine (D) Front of the engine | |
| 3056 Marine Engine Specifications | |
| Operating Range (rpm) | 1500 to 2600 (1) |
| Number of Cylinders | 6 In-Line |
| Bore | 100 mm (3.9 inch) |
| Stroke | 127 mm (5.0 inch) |
| Aspiration | TA (2) or NA (3) |
| Compression Ratio | 16:1 for the turbocharged aftercooled engine 16.5:1 for the naturally aspirated engine |
| Displacement | 6 L (365 in3) |
| Firing Order | 1-5-3-6-2-4 |
| Rotation that is viewed from the flywheel | Counterclockwise |
| Valve Lash Setting (Inlet) | 0.20 mm (0.008 inch) |
| Valve Lash Setting (Exhaust) | 0.45 mm (0.018 inch) |
| ( 1 ) | The operating rpm is dependent on the engine rating and the application. |
| ( 2 ) | Turbocharged aftercooled |
| ( 3 ) | Naturally aspirated |