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1. Despite compulsion of replacement of loose leaves radical and шатунных bearings in the course of performance of major repairs of the engine, it is necessary to subject a condition of old loose leaves to the most attentive studying as from results of such analysis it is possible to gather a lot of helpful information on the general condition of the engine.
2. The exit of bearings out of operation can result from a lack of greasing, hit of a dirt or extraneous particles, overloads of the engine, development of corrosion and other adverse influences. Without dependence by nature defect, the reason of its occurrence should be revealed and eliminated prior to the beginning of assemblage of the engine in order to avoid relapses.
3. For survey take loose leaves from the beds in the block of cylinders/kartere of the engine, radical and шатунных covers and the bottom heads of rods. Spread out the removed loose leaves on a pure equal working surface as their arrangement on the engine that will allow to correlate their condition to a condition of corresponding necks of a cranked shaft.
4. The dirt and extraneous particles get to the engine various ways. They can be left inside after end of major repairs as a result of the negligent relation to performance of procedures of cleaning, get through filters or ventilation system картера. Often the dirt gets at first to impellent oil and already together with it gets into bearings. It is not necessary to forget that in the course of normal deterioration of the engine metal sawdust is inevitably formed. If after performance of a recovery work not to give a proper attention to procedure of cleaning of the engine, in it by all means there are abrasive particles. Without dependence from a way of penetration into the engine, all extraneous particles appear sooner or later introduced in a soft surface of a working layer of loose leaves of bearings of sliding and are easily distinguished at visual survey of the last. The largest particles usually do not jam tightly in loose leaves, but deep furrows and teases leave on their working surfaces and surfaces corresponding necks of a shaft. The best preventive maintenance of this sort of occurrence of defects is the conscientious attitude to performance of cleaning of the engine after end of major repairs and installation during assemblage only absolutely pure components. Also it is not necessary to forget necessities of performance of regular and frequent change of impellent oil.
5. Oil starvation also can be caused the several reasons frequently closely interconnected with each other. It is necessary to carry an engine overheat to that (the leader to разжижению oils), overloads (in which result oil is superseded from bearings), oil leaks (connected with excessive size of a working backlash in bearings, deterioration of the oil pump, or excessive increase of turns of the engine), etc. passableness Infringement маслотоков, more often connected with negligence of installation of components at the assemblage conducting to рассовмещению of oil apertures, also causes reduction of giving of oil in bearings and, finally, to an exit of loose leaves out of operation. A characteristic sign of oil starvation is the wipe and replacement of a soft working layer of loose leaves from a steel substrate. Sometimes the temperature raises to such degree that on a substrate violet stains are formed.
6. It is necessary to remember that essential influence on service life of bearings is rendered also by a driving manner. To loading increase on the engine promote frequent full opening throttle заслонки, movement on small turns, etc. As a result occurs replacement of an oil film from a working backlash of bearings that conducts to a softening of loose leaves of the last and formation on their working surface of small cracks (fatigue deformation). Finally occurs отслоение separate fragments of a material of a working layer and their loss from a substrate.
7. Operation of the car in the conditions of a city cycle is frequently connected with fulfilment of set of short trips that conducts to development of corrosion of bearings as insufficient warming up of the engine promotes loss in it a condensate and to formation of chemically aggressive gaseous mixes. Aggressive products accumulate in impellent oil, forming шлам and acid and as oil continuously arrives in bearings, finally influence a material of loose leaves of the last, causing its oxidation and destruction.
8. Wrong installation of loose leaves at engine assemblage also conducts to their fast exit out of operation. At too dense installation it is inadmissible the size of a working backlash that is at the bottom of oil starvation of bearings is reduced. Hit between backs of loose leaves and beds of bearings of extraneous particles conducts to formation of sites of an eminence of a working surface of loose leaves and destruction of the last in the course of normal work of the engine.
9. Try not to touch working surfaces of loose leaves fingers as thus the risk of casual damage of a soft material of a blanket appreciably raises and inevitably there is its pollution.
10. As already it was mentioned above in the given Section, replacement of loose leaves at engine major repairs should be made without fail without dependence from their condition - attempt to ignore given requirement is capable to lead to only seeming economy. |