After starting the diesel engine, observe and check the readings of various instruments. Especially under idle conditions (650–700 rpm), 

the oil pressure should not be less than 100 kPa (1.02 kgf/cm²). Then, run the engine at 800–1000 rpm for 5 minutes to warm it up. 

Only after the coolant temperature rises to 55°C and the oil temperature reaches 45°C should you gradually increase the speed and load. 

Avoid sudden load increases or reductions whenever possible.

For new or recently overhauled diesel engines, it is not advisable to operate at full load immediately. Instead, 

limit the speed and load to 75% of the rated speed and power during the initial use period. After 60 hours of break-in operation, 

the running-in of moving parts will improve, enhancing the reliability and service life of the diesel engine.

Below, we provide a brief overview based on two types of diesel engines: “automotive diesel engines” and “non-automotive diesel engines”.

Automotive Diesel Engines

During the first 160 km of use after initial operation, the engine speed should be controlled within 1500–1800 rpm after warming up, 

and the vehicle should be run in high gear for break-in. Note that during this period, continuous idle operation should not exceed 

5 minutes at any time. Additionally, after completing the 60-hour break-in period, the engine must undergo mandatory maintenance 

at an authorized service center, including:

1) Clean the air filter, inspect air ducts, and replace the oil and diesel filters.

2) Drain the old oil promptly and replace it with new oil.

3) Inspect the fuel injectors and fuel lines.

4) Retighten cylinder head bolts to the specified torque.

5) Check and adjust valve clearance.

6) Check and adjust fuel injection timing.

7) Inspect belts, tensioners, idler pulleys, fan bearings, etc.

8) Inspect the turbocharger.

9) Check the tightening of the exhaust manifold and hoses.

10) Inspect all auxiliary components of the diesel engine.

11) Test-run and evaluate engine operation.

12) Inspect other relevant items as required.

Non-Automotive Diesel Engines

During the first 3 hours of operation after initial use, the diesel engine should be operated as follows:

1) Continuous idle operation should not exceed 5 minutes at any time.

2) The recommended operating condition is 75% load at the rated speed.

3) Continuous operation at full speed and full load should not exceed 5 minutes at any time.

4) After accumulating 800 km or 20 hours of operation, change the engine oil and filters.

Once the diesel engine is in normal use, regularly monitor all instrument readings and observe the overall operational dynamics. 

Frequently check the fluid levels of the cooling system and lubrication system. 

If any levels are found to be below specifications or leaks are detected, replenish them immediately or investigate and address the cause.

During operation, especially during sudden load reductions, be cautious to prevent the engine speed from exceeding the specified limit due 

to governor failure (commonly known as "runaway"). If this occurs, take immediate emergency shutdown measures and then investigate the cause.

Proper power rating of the diesel engine and reasonable matching with the working machinery's characteristics are prerequisites for ensuring reliability, 

long service life, and economical operation. Otherwise, the engine may operate under overload conditions, leading to unnecessary failures, 

or the load may be too small, resulting in underutilization of the engine's power. This is not only uneconomical but can also cause issues such as oil blow-by. 

Therefore, when selecting a diesel engine, users must consider not only the power requirements of the machinery but also its load rate 

(e.g., intermittent or continuous use) and the economic efficiency of operation, ensuring a reasonable match between the load characteristics 

and the engine's performance.

Use of Diesel Engines in High-Altitude Areas

The performance and usage of diesel engines in high-altitude areas differ from those in plains. 

High-altitude conditions bring specific changes, and we provide the following guidelines for users operating diesel engines in such regions:

1. Due to low atmospheric pressure and thin air, the oxygen content is significantly lower, especially for naturally aspirated diesel engines. 

    To improve combustion efficiency under high-altitude conditions, it is generally recommended to advance the fuel injection timing 

appropriately for naturally aspirated engines. The reduced air intake leads to poorer combustion conditions, preventing the diesel 

engine from delivering its rated power. Even with similar basic structures, different diesel engine models have varying rated power 

outputs and, thus, different capabilities in high-altitude environments.  

   For example, comparing the 6135Q-1 and 6135K-11 models:  

   - The 6135Q-1, with a rated power of 161.8 kW/2200 rpm, has minimal performance margin. 

     At high altitudes, its power decreases by approximately 12% for every 1,000 meters of elevation. 

     Therefore, during prolonged use in high-altitude areas, the fuel supply should be appropriately reduced based on local elevation.  

   - The 6135K-11, with a lower rated power of 117.7 kW/2200 rpm, has sufficient performance margin, giving it better high-altitude adaptability.  

   Due to reduced power and increased exhaust temperatures at higher elevations, 

   users should consider the engine's high-altitude performance and strictly avoid overload operation.  

   Turbocharging is highly effective in compensating for power loss in high-altitude areas. It not only restores power 

   but also improves exhaust emissions, restores dynamic performance, and reduces fuel consumption.

2. As altitude increases, ambient temperatures decrease by about 0.6°C per 1,000 meters. Combined with thin air, this makes starting 

   diesel engines more challenging in high-altitude areas. Users should adopt auxiliary starting measures suitable for low-temperature conditions.

3. Due to higher elevations, the boiling point of water decreases, while wind pressure and cooling air mass reduce. Additionally, 

    heat dissipation per kilowatt increases over time, making cooling systems less efficient in high-altitude areas. 

   Open cooling systems are generally not recommended; instead, pressurized closed cooling systems should be used to raise the coolant boiling point.

Characteristics of Turbocharged Diesel Engines

Given the mention of turbocharged diesel engines, we provide a brief overview of their usage characteristics:

1. Since 1989, turbocharged models in the 135 series diesel engines have been redesigned with increased compression ratios. 

   Some turbocharged models are also equipped with intake preheating devices to improve cold-start performance.

2. After starting the engine, wait for the oil pressure to rise before accelerating. Premature acceleration can damage turbocharger bearings. 

   After changing the engine oil, cleaning the turbocharger or filters, or if the engine has been idle for over a week, run the engine at idle, 

   loosen the oil inlet connection on the turbocharger slightly until oil seeps out, then tighten it and idle for a few more minutes before applying load.

3. Avoid prolonged idling, as it can cause oil leakage from the turbocharger into the compressor, leading to oil discharge through the exhaust pipe.

4. For new engines or after turbocharger replacement, remove the oil inlet pipe connection on the turbocharger and add 50–60 ml of oil 

   to prevent bearing damage due to oil starvation during startup.

5. Before shutting down the engine, idle for 2–3 minutes. Except in emergencies, 

    avoid sudden shutdowns to prevent turbocharger overheating and bearing seizure.

6. After shutting down the engine, listen for any rubbing or collision sounds between the turbocharger impeller and housing. 

    If such sounds are detected, immediately disassemble the turbocharger to check bearing clearance.

7. Ensure the sealing of intake and exhaust pipelines, as leaks can affect engine performance. 

    Regularly check for loose nuts or bolts and tighten hose clamps as needed. Replace sealing gaskets if necessary.