Compared with the gasoline engine, diesel engine abnormal sound diagnosis is more difficult to grasp, this is decided by the structure characteristics and working characteristics of the diesel engine, such as compression ratio, thermal load, work is relatively rough, big noise, broken oil cannot instantly, and even some diesel oil at the opening of the position of the people not easy to close, to the diagnosis of abnormal noise also brings inconvenience. However, the abnormal sound of the diesel engine has its specific rules, as long as the analysis and comparison, look at the phenomenon of grasping the essence, it is possible to find out its regularity.
Valve tappet
Beiben features V3 fittings valve tappet ring is the engine idling, heard similar valve clearance produced by big “blah” sound, the sound clear and rhythmic, when the temperature changes or single cylinder oil test, noise does not change, but the speed above can be weakened or disappeared.
The reason
North rush V3 parts valve push rod bending deformation.
The North-Benz V3 accessories tappet and tappet hole wear, the loss and the large gap.
The diagnosis and treatment methods
During the inspection, remove the cover of the valve chamber, hold down the side of the push rod close to the cylinder head by hand, and give the appropriate lateral force to the direction of rotation of the cam shaft, so as to reduce the swing when it moves up and down. Listen carefully, the sound is reduced or disappeared for the tappet.
Found that the tappet ring, first check whether the deformation of the push rod, if the deformation should be corrected or replaced. When new parts are changed, quality inspection must be taken into account.
When the rod is in good condition, check the tappet and tappet hole roundness, cylindricity or fit clearance is too large. Should be repaired in a timely manner, and the lubricating oil circuit inspection, maintenance.