D12 Engine- Efficiency Redefined: The Technology and Fuel Economy of the D12 Engine- High quality parts- 100% Factory price
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Efficiency Redefined: The Technology and Fuel Economy of the D12 Engine

Technical Parameters Of D12 Engine





Vertical, in-line, water-cooled, four-stroke, direct injection

Air inlet

Turbocharged and intercooled

NO. of cylinder





NO. of valve/



Crankshaft rotation direction(look from the free end)


Ignition sequence


Displacement (L)


Rated fuel consumption rate (g/kW.h)


Maximum combustion pressure (MPa)



Compression ratio


Oil fuel consumption ratio(%)


Starting mode

Electric starting

Charge ratio


Idle speed(r/min)



Crankshaft type

Integral type

Net weight(kg)



L×W×H (mm)


Working Principle of D12 Engine

D12 Engine
  • The D12 engine is a type of internal combustion engine commonly used in heavy-duty trucks and other large vehicles. It is a 12-cylinder diesel engine that operates on the principles of the diesel cycle.
The working principle of the D12 engine involves four strokes: intake, compression, combustion, and exhaust. Here’s a step-by-step explanation of each stroke:
  1. Intake Stroke: The intake stroke begins with the downward movement of the piston. As the piston moves down, the intake valve opens, allowing air to enter the cylinder. Simultaneously, the fuel injector sprays diesel fuel into the combustion chamber, creating a fine mist.
  2. Compression Stroke: Once the piston reaches the bottom of the intake stroke, it starts moving back upward, compressing the air-fuel mixture. Both the intake and exhaust valves are closed during this stroke. The compression raises the temperature and pressure of the mixture, preparing it for combustion. The compression stroke ends when the piston reaches the top of its stroke.
  3. Combustion Stroke: Just before the piston reaches the top of the compression stroke, the fuel in the combustion chamber is ignited by the heat of compression. This causes a rapid combustion or explosion of the fuel, generating a high-pressure gas that pushes the piston downward with force. The power generated by this explosion is transferred to the crankshaft through a connecting rod.
  4. Exhaust Stroke: As the piston reaches the bottom of the combustion stroke, the exhaust valve opens, and the piston moves upward again. This upward movement pushes the burned gases out of the cylinder through the exhaust valve and into the exhaust system. The exhaust stroke ends when the piston reaches the top of its stroke, and the cycle repeats.
  • The D12 engine operates with all 12 cylinders firing in a specific firing order, resulting in a smooth and continuous power delivery. It is designed to provide high torque and horsepower, making it suitable for heavy-duty applications.
  • It’s important to note that the specific design and features of the D12 engine may vary depending on the manufacturer and the particular model. However, the fundamental principles of the four-stroke combustion cycle remain the same.

Routine Maintenance And Care Of D12 Engine

The D12 engine is a heavy-duty diesel engine commonly used in trucks and industrial applications. To ensure its proper functioning and longevity, regular routine maintenance and care are crucial. Here are some important steps to follow:

  1. Regular oil changes: Change the engine oil at the recommended intervals or as advised by the manufacturer. This helps to keep the engine clean and lubricated, preventing excessive wear and tear.
  2. Air filter cleaning/replacement: Clean or replace the air filter regularly to maintain proper airflow into the engine. A clogged air filter can reduce engine performance and fuel efficiency.
  3. Fuel filter replacement: Replace the fuel filter at the recommended intervals to prevent contaminants from entering the engine. This helps to maintain optimal fuel quality and protect the fuel injectors.
  4. Coolant system maintenance: Check the coolant level regularly and ensure it is at the appropriate level. Also, inspect for any leaks or damages in the cooling system. Replace the coolant as per the manufacturer’s recommendations.
  5. Regular inspections: Inspect the engine for any leaks, loose connections, or damaged components. Pay attention to belts, hoses, and wiring harnesses. Address any issues promptly to prevent further damage.
  6. Proper engine warm-up and cool-down: Allow the engine to warm up before applying heavy loads and avoid immediate shutdown after heavy-duty operations. This helps to prevent thermal stress on the engine components.
  7. Regular engine performance checks: Monitor the engine’s performance, such as power output, fuel consumption, and exhaust emissions. Any significant deviation from the normal values may indicate an underlying issue that requires attention.
  8. Follow manufacturer’s guidelines: Always refer to the manufacturer’s manual for specific maintenance schedules, recommended fluids, and procedures. They provide the best guidelines for maintaining your D12 engine.
  • Remember, routine maintenance and care play a crucial role in extending the life of your D12 engine and ensuring its optimal performance. If you’re not familiar with engine maintenance, it’s advisable to consult a professional mechanic or follow the manufacturer’s service schedule.

The Price List of D12 Engine Parts

Application of D12 Engine

D12 Engine is a versatile powertrain that can be found in various vehicle models, including Sinotruk HOWO, HOWO A7, and SITRAK. Here’s a description of its application in each of these models:

  1. Sinotruk HOWO: The D12 Engine is the preferred power choice for the Sinotruk HOWO series of heavy-duty trucks. These trucks are known for their robust performance, high load-carrying capacity, and reliable operation. Equipped with the D12 Engine, Sinotruk HOWO trucks deliver excellent power and torque, making them suitable for demanding transportation and logistics applications.
  2. HOWO A7: The D12 Engine powers the Sinotruk HOWO A7 series, which is designed for long-haul transportation and challenging operating conditions. HOWO A7 trucks offer enhanced comfort, advanced features, and superior performance. With the D12 Engine, HOWO A7 trucks deliver exceptional power efficiency, ensuring reliable performance and fuel economy on long-distance journeys.
  3. SITRAK: SITRAK trucks, part of the Sinotruk lineup, benefit from the D12 Engine’s power and reliability. SITRAK trucks are known for their robust construction, superior carrying capacity, and excellent performance in demanding applications such as construction and mining. The D12 Engine provides ample power and torque for SITRAK trucks, empowering them to handle heavy loads and challenging terrains with ease.
  • Overall, the D12 Engine’s application in Sinotruk HOWO, HOWO A7, and SITRAK series ensures powerful and efficient performance, meeting the diverse needs of heavy-duty transportation across various industries.

Recommended Products of D12 Engine

Packing of D12 Engine

WP12 Engine-packaging-shipping

When packing D12 Engine, it is essential to ensure that they are properly protected to prevent any damage during transportation.

Here are some steps to pack D12 Engine effectively:
  1. Clean the parts: Before packing, make sure to clean the D12 Enginethoroughly, removing any dirt, grease, or debris. This will help maintain the quality of the parts during transit.
  2. Use appropriate packaging materials: Select suitable packaging materials to protect the D12 EngineConsider using sturdy cardboard boxes, foam inserts, bubble wrap, or packing peanuts to cushion and secure the parts.
  3. Wrap individual parts: Wrap each D12 Engineseparately with bubble wrap or foam padding to provide extra protection against impacts and vibrations. This will prevent any scratching or potential damage caused by friction.
  4. Consider organizing parts: If there are multiple D12 Engine, we will systematically organize them. We will use small plastic bags or compartments inside the packaging to keep the parts separate and avoid entanglement or potential damage due to contact.
  5. Use proper sealing: Once the parts are securely placed inside the packaging, ensure the boxes are properly sealed to prevent any accidental opening or shifting of the contents during transit. Use strong packing tape to seal all the edges and corners of the box.
  6. Label the packages: Clearly label the packaging with appropriate shipping labels, including the recipient’s address, contact information, and any other relevant details.
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