Automobile maintenance technology how to repair automobile engine water pump
  • Automotive

The pump is one of the important parts of the engine cooling system. The function of the pump is to pressurize the coolant to ensure that it circulates in the cooling system to accelerate the emission of heat. As a long-term running device, the pump will also fail during the operation. The fault diagnosis of tools / raw water pumps is relatively simple in general. In the case of leakage of the cooling system, the odor of the thermal antifreeze can be smelled, but a check must be carried out to find out whether the cooling water is leaking from the shaft seal of the pump. A small mirror and light can be used to check whether the water leakage of the pump vent hole. Regular maintenance should be carried out to check the loss of coolant in the tank. Leakage is the first fault of the pump. Noise is No. second fault. The phenomenon that the pump shaft is killed due to the abrasion of the bearing is very rare. Once this happens, the wind and radiator will be damaged. Method / step 1. check the wear and damage of pump body and pulley, and replace it if necessary. Check whether there is any bending of the pump shaft, the wear degree of the journal, and whether there is any damage to the shaft end thread. Check whether the blades on the impeller are broken and the wear of shaft holes is serious. Check the wear degree of water seal and bakelite gasket, for example, new parts should be replaced if exceeding the limit of use. Check the wear condition of the bearing and use the meter to measure the clearance of the bearing. If more than 0.10mm, the new bearing should be replaced. 2. after the pump is removed, it can be decomposed sequentially. After decomposing, the parts should be cleaned and checked one by one to see if there are any defects such as cracks, damage and wear. If serious defects are found, they should be replaced. 3. water seal and seat repair: water seal, such as worn slotting, can be grinded with sand cloth, such as wear and tear should be replaced; water seal, such as a rough scratch, can be repaired by a flat reamer or on a lathe. A new water seal should be replaced during overhaul. 4. in the pump body the following damage is allowed to repair: the length is within 3Omm, the crack is not stretched to the bearing seat hole; the flange joint with the cylinder head has a broken part; the oil seal hole is damaged. The bending of the pump shaft should not exceed 0.05mm, otherwise it should be replaced. The blade breakage of the impeller should be replaced. The wear of the shaft diameter of the pump shaft should be changed or repaired. 5. check whether the bearing of the pump is flexible or abnormal. If there is any indication that the bearing is defective, it should be replaced. 6. when the pump is assembled, rotate it with your hand. The pump shaft should be free from stagnation, and the impeller and pump shell should not be rubbed. Then check the displacement of the pump. If there are any problems, check the cause and exclude. If the pump fails, the coolant will not be able to reach the corresponding place, its performance will not be able to effectively play the I, and ultimately affect the working conditions of the engine. Therefore, it is necessary to strengthen the inspection of the water pump. In terms of service life, the biggest change in the design of the pump is the appearance of ceramic seals a few years ago. Compared with the rubber seals or leather seals used before, the ceramic seals are more wear-resistant, but it also has the disadvantage of being easily scratched by hard particles in the cooling water. Although continuous improvement has been made in the design to prevent failures of the pump seal, up to now, the sealing of the pump can not be guaranteed. Once the seal is leaking, the lubrication of the pump bearing will be washed away.