Some normal issues of diesel generators and its solutions

1. The air filter is not clean

Uncleanness will increase resistance, reduce air flow and reduce inflation efficiency, resulting in insufficient engine power. Clean the dust on the diesel air filter core or paper filter element as required, and replace the filter element if necessary.

2. Exhaust pipe blocked

Blocked exhaust pipe will reduce fuel using efficiency; power down. Check whether the exhaust resistance increases due to too much carbon deposition in the exhaust pipe. Generally, the exhaust back pressure should not exceed 3.3kpa, and the carbon deposit in the exhaust pipe should be removed frequently at ordinary times.

3. The fuel supply advance angle is too large or too small

Too large or too small fuel supply advance angle will cause the fuel injection time of the oil pump to be too early or too late (too early fuel injection time will lead to insufficient fuel combustion, too late will lead to white smoke and insufficient fuel combustion), so that the combustion process is not in the best state. At this time, check whether the screw of the fuel injection drive shaft adapter is loose. If it is loose, readjust the fuel supply advance angle as required and tighten the screw.

4. Piston and cylinder liner strained

As the piston and cylinder liner are seriously strained or worn, and the friction loss increases due to the rubber binding of piston ring, the mechanical loss of the engine increases, the compression ratio decreases, the ignition is difficult or the combustion is insufficient, the lower inflation increases and the air leakage is serious. At this time, replace the cylinder liner, piston and piston ring.

5. There is a problem with the fuel system

(1) The air in the fuel filter or pipeline is blocked, resulting in blocked oil circuit, insufficient power and even difficult ignition. Clean the diesel filter element with the air entering the pipeline and replace it if necessary.

(2) The damage of fuel injection coupling causes oil leakage, biting or poor atomization. At this time, it is easy to cause cylinder shortage and insufficient engine power. It shall be cleaned, ground or renewed in time.

(3) Insufficient fuel supply of the fuel injection pump will also cause insufficient power. Check, repair or replace the coupling in time, and readjust the fuel supply of the fuel injection pump.

6. The cooling and lubrication system is faulty

Overheating of diesel engine is caused by the failure of cooling or lubrication system. In this case, the water temperature and oil temperature will be too high, and cylinder pulling or piston ring jamming is easy to occur. When the exhaust temperature of diesel engine increases, check the cooler and radiator for scale.

7. The cylinder head group is faulty

(1) Due to exhaust leakage, the intake air is insufficient or mixed with exhaust gas, resulting in insufficient fuel combustion and power reduction. The mating surface of valve and valve seat shall be polished to improve its sealing performance, and it shall be replaced if necessary.

(2) Air leakage at the joint surface between the cylinder head and the engine body will make the air in the cylinder enter the water channel or oil channel, causing the coolant to enter the engine. If it is not found in time, it will lead to "sliding shoe" or black smoke, resulting in insufficient power of the engine. Due to the damage of the cylinder gasket, an air flow will rush out of the cylinder gasket during speed change, and blisters will appear at the gasket when the engine is running. At this time, tighten the cylinder head nut or replace the cylinder head gasket according to the specified torque.

(3) Incorrect valve clearance will cause air leakage, resulting in reduced engine power and even difficult ignition. The valve clearance should be readjusted.

(4) The damage of valve spring will make it difficult to return the valve, the valve leaks and the gas compression ratio decreases, resulting in insufficient engine power. Replace the damaged valve spring in time.

(5) Leakage of fuel injector mounting hole or damage of copper pad will cause cylinder shortage and insufficient engine power. Remove it for maintenance and replace the damaged parts. If the inlet water temperature is too low, it will increase the heat dissipation loss. At this time, the inlet temperature should be adjusted to meet the specified value.

8. The surface of connecting rod bearing bush and crankshaft connecting rod journal is roughened

This situation will be accompanied by abnormal sound and oil pressure drop, which is caused by blocked oil passage, damaged oil pump, blocked oil filter element, low oil hydraulic pressure or even no oil. At this time, the side cover of the diesel engine can be removed, and the side clearance of the connecting rod big end can be checked to see whether the connecting rod big end can move back and forth. If it cannot move, it indicates that it has been bitten, and the connecting rod bearing bush should be repaired or replaced.