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I. If the slurry pump will not start, the power supply should be checked first: ensure that the connections are secure； Are the switch contacts tight? ； Is the fuse blown? ； Check whether there is a phase imbalance in the three-phase power supply. In the event of an open circuit, poor contact, blown fuse, or missing phase, the cause should be identified and repaired promptly. Next, check for mechanical faults within the water pump itself; common causes include overly tight packing or blockages caused by debris stuck between the impeller and the pump casing ； The pump shaft, bearings, and leak reduction rings are rusted ； Severe bending of the pump shaft, etc. Exclusion method: Relax the filler and clear the water guide channel ； Disassemble the pump body to remove debris and rust ； Remove the pump shaft to correct it or replace it with a new one. II. Overheating of the auxiliary drive motor. Reason 1: It is related to the power supply; the voltage of the slurry pump may be too high or too low. Under certain load conditions, if the voltage deviates by more than +10% to –5% of the rated value, it can cause the motor to overheat ； If the three-phase voltage of the power supply is asymmetric, with an imbalance between the phase voltages exceeding 5%, it can cause the windings to overheat ； Operation with a missing phase: Experience shows that over 85% of agricultural motors get damaged as a result of operating with a missing phase; therefore, phase-loss protection devices should be installed on these motors. The second reason is related to the water pump: an inappropriate power level is used, meaning a motor that is not strong enough for the task is employed; as a result, the motor operates under overload conditions for extended periods, causing its temperature to rise excessively ； Motors that are started too frequently, or those designed for short-duration or intermittent operation, are forced to work continuously. The number of starts should be limited, appropriate thermal protection should be used, and the motor should be operated according to the rated specifications indicated on it. Reason three is related to the motor itself: an incorrect wiring method, where a delta connection was mistakenly used in place of a star connection, which caused the motor’s temperature to rise rapidly ； The stator windings may suffer from inter-phase short circuits, turn-to-turn short circuits, or local grounding; in mild cases this causes localized overheating of the motor, while in severe cases it leads to insulation damage ； The squirrel-cage rotor has broken bars or defects; after the motor operates for 1 to 2 hours, the core temperature rises rapidly ； If there is a malfunction in the ventilation system, check whether the fan is damaged, whether its rotation direction is correct, and whether the ventilation channels of the slurry pump are blocked ； Bearing wear and rotor eccentricity cause the stator and rotor cores to rub against each other, generating metallic knocking sounds; the temperature of the cores rises rapidly, and in severe cases the motor starts to smoke or even the windings get burned out. The fourth reason is related to the working environment: the motor windings become damp, or dust, oil, and other substances accumulate on them, resulting in reduced insulation. The insulation resistance of the motor should be measured, and it should be cleaned and dried ； The ambient temperature is too high. When the ambient temperature exceeds 35°C, the high inlet air temperature can cause the motor to overheat; measures should be taken to improve its operating environment. Such as setting up shelters for shade, etc. Note: In the event of a fault caused by electrical issues, it should be repaired by an electrician with professional qualifications; those with only limited knowledge should not attempt repairs, to prevent accidents that could cause injury. III. Overheating of the slurry pump Cause: Damaged bearings ； The clearance between the rolling bearings or bracket cover of the slurry pump is too small ； The pump shaft is bent or the two shafts are not aligned ； The tape is too tight ； Lack of oil or poor oil quality ； The balance holes on the impeller are blocked, causing the impeller to lose its balance and increasing the thrust in one direction. Exclusion method: Replace the bearing ； Remove the rear cover and install shims between the bracket and the bearing housing ； Inspect the pump shaft or adjust the concentricity of the two shafts ； Adjust the tape tension appropriately ； Fill it with clean butter, such that the butter occupies about 60% of the space inside the bearing ； Remove the blockages from the balance hole. IV. Insufficient slurry flow rate from the slurry pump Cause: The rotational speed of the slurry pump is not appropriate, or the belt is slipping, resulting in a low rotational speed ； The installation angle of the axial flow pump blades is too small ； Insufficient head, too long pipeline, or straight bends in the pipeline ； The suction lift is too high ； Local blockage of the bottom valve, pipelines, and impeller, or damage to the impeller ； The water outlet pipe is leaking severely. Exclusion methods: Restore the rated speed, remove oil buildup from the belt, and adjust the belt tension properly ； Adjust the blade angle, lower the installation height of the water pump, shorten the pipelines or change their curvature ； Seal the leak in the water pump by compressing the packing ； Remove the blockage and replace the impeller ； Replace the leak-reducing ring to seal the leak. V. The slurry pump does not draw in water (no slurry is generated). Reasons: There is air inside the pump or air accumulation in the water inlet pipe; the bottom valve does not close properly resulting in insufficient water filling; the packing of the vacuum pump leaks severely; or the gate valve or check valve does not close properly. Exclusion method: First increase the water pressure, then fill the pump body with water, and finally turn it on. At the same time, check whether the check valve is airtight and whether there are any air leaks in the pipes and connections; if leaks are found, disassemble them, apply lubricant or sealant to the connections, and tighten the screws. Inspect the oil seal ring of the water pump shaft; if it is severely worn, replace it with a new one. The pipeline is leaking fluid or air. The nut might not have been tightened properly during installation. If the leakage is not severe, cement can be applied to the area where air or water is leaking, or a cement paste mixed with asphalt oil can be used. For temporary repairs, some wet mud or soft soap can be applied. If there is leakage at the joint, the nut can be tightened using a wrench; if the leakage is severe, the assembly must be disassembled again and the cracked pipe replaced ； Reduce the head by submerging the pump outlet 0.5m underwater. VI. Severe vibration of the slurry pump Cause: Unbalanced electric rotor ； Poor coupling fit ； Bearing wear and bending ； The parts of the rotating mechanism are loose or damaged ； Reasons such as loose pipeline supports. Adjustment, repair, reinforcement, straightening, replacement, and other methods can be employed separately to address the issue. The above situations are common causes of pump failures, but they are not the only ones. When dealing with such failures in practice, one should follow the principle of starting with the external aspects before moving on to the internal ones, and avoid acting blindly.