Common Fault Diagnosis and Removal of Cooling System

The main fault of the cooling system is that the temperature of the engine is too high, which is mainly divided into three situations: the cooling water is sufficient but the temperature is too high, the cooling water is insufficient and the temperature is too high, and the temperature is suddenly too high during work.

The engine temperature is too high

1) The cooling water is sufficient but the temperature is too high

① Phenomenon The engine cooling water meets the standard and there is no water leakage, but the power is insufficient during operation, and the water temperature exceeds 90°C or even boils (commonly known as boiling).

②The reason is that the fan belt is too loose or slipped; the large circulation of the thermostat or the water distribution pipe is not working well; the engine radiator outlet pipe is sucked, deflated and deposited too much, and other reasons, such as the ignition time is too late, the mixture is too rich or too lean, etc. .

③Diagnosis and elimination, first check whether the fan blades are deformed, and whether the belt is too loose or slipping. If it is good, then check whether the water circulation system is normal, whether the rubber hose is sucked, whether the pipe wall is delaminated, whether the thermostat is invalid, whether the radiator is blocked, whether the blades are dumped too much, whether the scale of the cylinder is too much, and whether the water distribution pipe is not. damaged or blocked. If overheating after inspection, technical use reasons should be considered

2) The cooling water is insufficient and the temperature is too high

① Phenomenon The engine cooling system cannot accommodate the specified amount of cooling water; the cooling water consumption is abnormal during operation. The reason is that the radiator is too fouled, partially blocked, leaks or the intake and exhaust valves fail; the water pump leaks; the cooling water is not drained and frozen in winter, and the cylinder bore communicates with the cylinder; the valve chamber wall is ruptured and leaked, cooling Water leaking from other parts.

③Diagnosis and elimination First, check whether the cooling water capacity is sufficient, whether the radiator is in good condition, and whether there is water leakage in each part of the cooling system. In winter, pay attention to check whether the radiator is frozen and whether the water pump is leaking. If there is no water leakage outside the cooling system, but the cooling water consumption is still relatively fast, it is necessary to consider whether there is water leakage inside the cooling system, that is, if the oil dipstick is pulled out and there is water, it means that the cylinder is full or the intake passage is broken and the water leaks or the cylinder gasket water passage Communication with the cylinder is broken. At the same time, it should also be checked whether the exhaust reading of the heat exchanger is inappropriate.

3) The engine suddenly overheats

①Phenomena, the pointer of the water temperature gauge quickly indicates the position of 100"C; the engine power drops significantly; when the cold car is started, the water temperature rises rapidly and boils, and it becomes normal after supplementing the cooling water.

②The reason is that the fan belt is broken or the fixed fulcrum of the generator is loose or displaced; the main valve of the thermostat falls off; the water pump shaft and the impeller are loose, and the cooling system leaks seriously; the cylinder gasket is damaged, the water pump communicates with the cylinder, and the high-pressure airflow enters the waterway.

③Diagnosis and elimination during operation If the engine suddenly overheats, you should pay attention to the dynamic of the ammeter. If the engine speed is increased, the ammeter shows no charging or the charging indicator lights up, indicating that the fan belt is broken and the water pump does not work. If you touch the radiator and engine by hand, and find that the temperature of the engine is high and the temperature of the radiator is low, it means that the water pump shaft and the blades are loose. If the temperature rises rapidly and the cooling water boils when the cold car is started, it is mostly because the main valve of the thermostat falls off. Check the cylinder head gasket for damage if necessary. Dedicated for tinting

Engine temperature is too low

① The indication value of the thermometer is lower than the normal working temperature of the engine, the engine is weak, and the muffler has a blasting sound; the fuel consumption increases.

②The reason is that thermal insulation facilities are not used in severe cold areas; the thermostat fails; the engine lubricating oil is too much.

③Diagnosis and troubleshooting Check the amount of lubricating oil of the engine. If it is too much, it should be released, keep an appropriate amount of lubricating oil, and then check

Our website also provides solenoid valve 4903523, you can buy a variety of spare parts for excavators, and aerial platforms on our website.