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 operation device, the use of the process, the pump will also fail, how to repair these failures, a lot of people will feel that this inspection is very complex, a failure to direct repair, in fact, there are some small fault owners can be completely solved, do not need to spend "unjust money". If the pump is damaged or damaged in use, the following inspection and repair can be done. 1. check the pump body and pulley wear and damage, if necessary, should be replaced. 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. After the 2. water pump is taken out, it can be decomposed in order. 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 hands. The pump shaft is not stuck, and the impeller and the pump shell are not 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, and its performance will not be effectively played, thereby affecting the working condition of the engine. Therefore, it is necessary to strengthen the inspection of the water pump.