Abnormal noise of wheel loader and forklift diesel engine——Crankshaft bearing noise

The cause of the crankshaft bearing ringing is the same as the rod noise. The signs are: the noise is duller than the knocking cylinder, piston pin and rod noise. When the fuel is rushed or the speed is reduced suddenly, the noise is clear; if the bearing alloy layer is burned out or falls off, the engine of the wheel loaders will shake. The sound is obvious and clear during heavy load operation. The sound does not change when the engine temperature changes.
When bearing noise occurs, the single-cylinder "cylinder-breaking" test has no obvious change; in the "cylinder-breaking" test of two adjacent cylinders, the noise will decrease or disappear. In addition, you can also use a metal rod or a screwdriver with a wooden handle to touch the bearings of the external body of the diesel engine to judge.

Note: If the noise is caused by the excessive clearance between the bearing and the bearing neck, the oil pressure will drop significantly.