Fuel System Maintenance of 200kVA Diesel Generator

Standard configuration of 200kVA diesel generator fuel system

The main components of the fuel system of the unit include: fuel tank, fuel supply pump, fuel filter, manual oil pump, fuel injection pump, fuel nozzle, and related fuel pipes.

Only use fuel that meets the quality specified in the following standards. Strictly maintain cleanliness when refueling and working on the fuel system. When working on the fuel system, it is necessary to confirm that the engine has cooled down. Fuel splashing onto hot surfaces or electrical components may cause a fire.

① The composition of fuel specification. Diesel has a very important impact on the operation, service life, and emission composition of diesel engines. In order to achieve the required power, fuel economy, and meet the emission standards set by the local environmental protection department, only clean light fuel that meets international and national standards should be used. Light diesel is a fuel used in high-speed diesel engines above 1000r/min. The current standard for light diesel products is GB252-2000 （Light Diesel）, and the classification of diesel grades is based on the freezing point of diesel. Customers should choose the appropriate diesel grade based on the temperature of their workplace.

② Precautions

I. The fuel recommended in the operation manual must be used. For 200kVA diesel generator, using low-quality fuel can cause the control rod to stick and the engine to rotate excessively, causing damage to the unit and even serious personal injury. Poor quality fuel can also shorten maintenance cycles, increase maintenance costs, and reduce the normal service life of the unit.

II. When adding fuel, there is usually a risk of fire and explosion. Smoking is prohibited when refueling.

III. Do not allow fuel oil to overflow the fuel tank, and the fuel tank cap should be securely sealed.

IV. Water in the fuel can cause metal components in the fuel system to rust, and it is also easy for fungi and microorganisms to grow in the fuel tank, thereby blocking the filter. It is recommended that users install an oil-water separator for commonly used units or when the water content of the fuel is relatively high. Make sure that the fuel entering the body is free of water or other impurities.

③ Replace fuel filter

I. Keep it clean and do not allow any dirt to enter the fuel system.

II. In order to avoid the fire caused by the fuel splashing onto the hot surface, the replacement of fuel filter must be carried out in cold condition.

III. Remove the filter and apply a small amount of lubricating oil to the sealing gasket of the new filter. Screw on the filter by hand to make its sealing gasket come into contact with the seat. Then tighten again, do not tighten too much, and exhaust the air from the fuel system.

IV. Start the diesel generating set and check for any leaks.

④ Fuel injection pump

The fuel injection pump is driven by the timing gear transmission mechanism inside the diesel engine. The setting of the pump is measured using a graduation meter when the base circle of a specific crankshaft angle rises. 

⑤ Fuel injector

I. Distribute fuel oil evenly to ensure reliable ignition and combustion

II. Directly inject fuel oil into the combustion chamber and provide the optimal mixture of fuel oil and air. The injection pressure can be pre adjusted by the spring.

⑥ System exhaust

If there is gas mixed in the fuel system, it may affect the normal start and operation of the unit. The exhaust of the fuel system can be carried out as follows:

Check to ensure that the fuel line connectors are not loose. Loosen the air bleed screw on the fuel filter, press the manual oil pump until there is no bubble in the spilled fuel, and then tighten the air bleed screw. Continue pumping oil 15-20 times to check for leaks.

Usually starts the unit by removing air through the low-pressure oil circuit. If it is still necessary to remove air from the high-pressure fuel pipe, loosen the nut of the high-pressure fuel pipe at one end of the fuel injector, press the manual oil pump until there are no bubbles in the spilled fuel, and then tighten the nut. This is done cylinder by cylinder to fill the fuel injectors of each cylinder with fuel.

When probing for fuel oil leaks, please protect your fingers. Oil that seeps out under high pressure can soak into your skin.

If the charging generator is located under the oil filter, please ensure that it is well covered, as spilled oil stains may damage the motor.