The engine water pump is an important component in the engine cooling system. In the engine cylinder, there are multiple water channels for coolant circulation, which are connected to the radiator (commonly known as the water tank) placed at the front of the car through water pipes to form a large water circulation system. At the upper water outlet of the engine, there is a water pump, usually with a thermostat. The water pump is driven by a belt to make the coolant flow quickly in the cooling water channel of the engine, pump out the hot water in the engine cylinder water channel, and pump in the cold water after heat dissipation, so that the engine maintains normal working temperature.
The frequency of use and use environment of the water pump cause its after-sales problems to be very frequent and there are many conditions. Among them, the more common after-sales problems are mainly water leakage, and water leakage is divided into two situations: water leakage after use and leakage when installed. Through the investigation and disassembly analysis of a large number of faulty parts, it is concluded that there are mainly 8 specific reasons for water pump leakage:
1.Leakage caused by sealing gasket
During the installation of the water pump, if sealant is illegally applied to the pipe mouth and the sealing gasket, the glue will harden the sealing gasket, causing the sealing function to fail. At the same time, the hardened rubber block enters the water path, and finally enters the thermostat and water seal after circulation. If it enters the thermostat, it will cause the thermostat to be unable to close and remain in a large cycle; if it enters the water seal, it will cause the water seal to wear and cause water leakage;
Notice! When installing the water pump, it is forbidden to apply sealant.
2.Leakage caused by oil/butter applied to the gasket
When installing the water pump, apply engine oil or butter to the gasket, etc. The engine oil will cause the gasket to foam and break, resulting in failure of the sealing function and water leakage. If you must apply something for lubrication during installation, you can apply antifreeze or special grease provided by the manufacturer to the gasket.
Notice：When installing the water pump, do not apply engine oil or butter.
3.Failure to use regular antifreeze leads to leakage
Using inferior antifreeze or even using tap water directly will cause rust inside the pipes. Inferior antifreeze will produce turbid water in the pipes. When rust and mud enter the water seal, it will wear out the water seal and cause water leaks.
Notice：When installing a water pump, it is forbidden to use inferior antifreeze or tap water. Regular brand antifreeze must be used and the pipes must be cleaned when necessary.
4.Leakage caused by failure to replace accessories synchronously
When replacing the water pump, the O-rings on the pipeline need to be replaced. However, the pressure change performance of the old O-rings has long been lost during the use of the original products, and they no longer have a sealing effect.
Notice:When installing the water pump, the relevant sealing rings and joints must be replaced simultaneously.
Piston Mitsubishi 4G69 69SA MN163080
The next issue will introduce the remaining four aspects...
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