The safety device of the wheat thresher should be complete, and the transmission part should have a safety cover. The motor and the thresher should be matched. It is strictly forbidden to operate without training. The number of people should be appropriate, the division of labor should be clear, and the feeding amount should be uniform and appropriate. It is not allowed to push the wheat into the drum with forks, woods and other tools. The human arm must not reach into the feeding port to prevent it from being injured by the rotating drum. Common malfunctions: 1, threshing is not clean: common reasons are low drum speed, large threshing gap, large groove and concave plate wear, too much feeding; elimination method: increase the speed, adjust the gap, replace the concave plate, reduce the feed; 2, unclear separation: common reasons are insufficient air volume or wind direction, wheat threshing machine screen hole damage or excessive gap, the grain is too wet; elimination method: adjust the air volume to the appropriate position to check the machine sieve hole, adjust the gap; 3, the drum is blocked: the reason is that the grain is too wet and the feeding amount is too large, the drum rotation speed is too low, the transmission belt is slipping; the elimination method: turning the crop, feeding evenly and continuously, appropriately increasing the rotation speed, and tightening the belt tension; 4, grain breakage: the reason is that the threshing gap is too small, the drum rotation speed is too high, the feeding grain is uneven; the elimination method: appropriately adjust the gap, reduce the rotation speed, and feed continuously evenly; 5, the drum of the wheat thresher has noise: the bolt is loose, the concave plate is deformed, and the threshing gap is small; the elimination method: tightening the screw, repairing the concave plate, adjusting the gap; 6. The motor of the wheat thresher is overheated: too much feed causes the load to be too large, the ventilation is poor, and the heat cannot be dissipated; the elimination method: reduce the feed amount, remove the debris around the motor, check the wire and voltage.