When the small loader is running at high speed, if there is "thrumming, thrumming" muffled sound, it is particularly obvious when reducing the throttle, which is caused by too large axial clearance of the spindle tile; Along the cylinder are similar to the sound of a small hammer tapping iron block, exhaust pipe blue smoke (accompanied by burning oil phenomenon), with a long handle screwdriver at the cylinder body is easier to hear, it can be determined that the piston ring gap is too large or ring broken.

In the small loader cylinder full length part to hear the dull "empty dong, empty dong" knocking sound, and open the oil mouth cover found that there are bubbles (indicating leakage phenomenon), this is caused by the piston and cylinder liner clearance is too large; If in the same part slightly by the direction of the crankshaft to hear the "ga, ga, ga" percussion sound, it is the connecting rod distortion caused by its swing in the work of the knocking sound, the last two kinds of sound in the change of diesel engine speed is more obvious, and easier to distinguish.

When the small loader suddenly changes the load, in the vicinity of the crankcase can clearly hear the short dull knocking sound, and with the increase of the load or speed and dramatic changes, the sound increases, no load is not obvious. This is caused by excessive wear of connecting rod tile and connecting rod journal clearance is too large; If a cylinder of diesel engine is cut off, if the abnormal sound immediately disappears, it indicates that the cylinder connecting rod tile sound.