Car water pump is one of the important components of the car engine cooling system, it is divided into automotive electric water pump and machine car water pump according to the driving form. The main function of the car water pump is to pressurize the cooling fluid (Such as water and coolant ) to ensure its circulation in the cooling system and accelerate the heat dissipation. As a long-running device, the car water pump will malfunction during use.
Generally speaking，fault diagnosis of the electric coolant pump is relatively simple . The smell of hot coolant can be smelled, in the case of leakage in the cooling system. But carry out some inspection is needed to find out whether the cooling water is leaking from the pump shaft seal. People can use a small mirror and light to see if there is any water leakage at the pump vent. In additional, regularly maintenance to the cooling system from time to time, and pay attention to check the loss of water tank coolant.
Water leakage is the number one failure of the pump, and noise is the second failure. The phenomenon of the pump shaft biting due to the abrasion of the bearing is very rare. Once this phenomenon occurs, the wind and the radiator will be damaged.
6 Steps to repair a car water pump
How to cool it down is an important step to ensure the life of the engine, after a car engine server for a long time? And the engine water pump has such an important function. Therefore, the majority of car owners should not miss the overhaul of the pump during daily maintenance and repair. Now VOVYO Technology Co., Ltd will introduce you the 6 steps of repairing the pump to ensure the smooth circulation of the pump.
- 1. check the pump body and pulley for wear and damage, and replace if necessary. Inspect the water pump shaft for bending, journal wear, and shaft end threads for damage. Check whether the blades on the impeller are broken or the shaft hole is seriously worn. Check the degree of wear of the water seal and bakelite gasket. If the usage limit is exceeded, new parts should be replaced. Check the wear of the bearing. You can measure the clearance of the bearing. If it exceeds 0.10mm, you should replace the new bearing.
- 2. Decompose the pump in order after it taken out from the car. Clean all the parts after the pump dis-assembly, and check them one by one to see if there are defects such as cracks, damage and wear. Then replace them with new parts, if there are serious defects.
- 3. Repair of water seal and seat: Smooth water seal with sand cloth, if it is worn and grooved, or even replace them with new parts if it is worn out; Repair the water seal seat with a flat reamer or on a lathe, if it is rough and scratched. Replace the seal assembly with a new one is needed during the overhaul.
- 4. Welding repair is allowed when there are the following damages on the pump body: the length of crack is within 30mm, and does not extend to the bearing seat hole; Flange that is engaged with the cylinder head has a broken part; Oil seal seat hole is damaged. The bending of the pump shaft must not exceed 0.05mm, otherwise replace it. Replace the Impeller blade if it damaged. Replace the pump shaft if its bore diameter is severely worn, or repair it.
- 5. Check the pump bearing to see whether it rotates flexibly or has abnormal noise. If there is, it shows that there is some problem with the bearing, then replace it with a new one.
- 6. Runs the rotor by hand, after the car water pump assembled, the pump shaft should be free of stagnation, and the impeller as well as the pump casing should be free of friction. Then check the displacement of the pump, investigate the cause and eliminate it, if there is a problem. The coolant will not reach the corresponding place, if the water pump fails. Moreover, its performance will not be effectively exerted, which will ultimately affect the working condition of the engine. Therefore, the car owner should strengthen the inspection of the car water pump.