Jeep Grand Cherokee

1993-1999 of release

Repair and car operation

Jeep Grandee Cheroki
+ Jeep Grand Cherokee brand Cars
+ Settings and routine maintenance
+ Ryadny six-cylinder engine
+ V8 Engine
- Procedures of the general and major maintenance of the engine
   General information
   Major maintenance of the engine - the general information
   Check of kompressionny pressure in cylinders
   The diagnostic checks made by means of the vacuum gage
   Methods of removal of the engine and necessary precautionary measures
   Removal and engine installation
   Options of restoration of the engine
   Order of dismantling of the engine
   Dismantling of a head of cylinders
   Cleaning and check of a condition of a head of cylinders
   Service of valves
   Assembly of a head of cylinders
   Removal of shatunno-piston assemblies
   Removal of a cranked shaft
   Cleaning of the block of the engine
   Check of a condition of the block of the engine
   Honingovaniye of cylinders
   Check of a condition of shatunno-piston assemblies
   Check of a condition of a cranked shaft
   Check of a condition of radical and shatunny bearings
   Engine assembly order after completion of its major maintenance
   Installation of a cranked shaft and check of gaps of radical bearings
   Installation of piston rings
   Installation of shatunno-piston assemblies and check of gaps in shatunny bearings
   The first start of the engine after major maintenance
+ Systems of cooling, heating and air conditioning
+ the Power supply system and production of the fulfilled gases
+ System of electric equipment of the engine
+ Systems of decrease in toxicity of the fulfilled gases and engine management
+ Manual box of gear shifting
+ Automatic transmission
+ Transfer case
+ Coupling and transmission line
+ Brake system
+ Suspension bracket and steering
+ Body
+ System of onboard electric equipment
+ Governing bodies and operation receptions

Check of a condition of radical and shatunny bearings

In spite of the fact that replacement of loose leaves of radical and shatunny bearings by the new is made in the course of major maintenance of the engine without fail, the condition of the old should be subjected to the most attentive studying as the analysis of its results can give valuable information on the general condition of the engine.

Typical defects of bearings of a cranked shaft.

The exit of bearings out of operation can result from insufficient greasing, hit of extraneous particles in them, overloads of the engine and impact of corrosion. Irrespective of character of the reason of an exit of bearings out of operation, it should be eliminated prior to the beginning of engine assembly in avoidance of recurrence at operation of the restored unit.

For condition check, take loose leaves from covers of radical and shatunny bearings, beds in the block of the engine and the bottom heads of rods and spread out them on an equal pure surface in the same order in what they were established on the engine. It will allow to connect problems of bearings with a condition of the corresponding necks of a shaft.

Dirt and extraneous particles can get to the engine various ways. They can be left at assembly or get via filters or system of ventilation of a case (PCV), to get to bearings together with oil. Metal sawdust can be left after carrying out stanochny processing or is developed in the course of normal functioning of the engine. Abrasive particles often remain in the engine after carrying out regenerative procedures, in particular if is not given due consideration to cleaning of the block and internal components. Irrespective of a way of penetration into the engine, extraneous particles and dirt as a result appear introduced in a soft material of bearings where can be easily identified more often. Large particles do not get stuck in bearings, and leave scars on surfaces of loose leaves and shaft necks. The best preventive measure for prevention of an exit of bearings out of operation is the conscientious attitude to performance of cleaning of the engine and its components after major maintenance with application of recommended methods of its performance. Important value has also carrying out regular and frequent change of impellent oil and the oil filter.

The lack of greasing (or its termination) can be a consequence of several, often interconnected, the reasons. It is necessary to carry to them: an overheat (the leader to an istoncheniye of an oil layer), engine overloads (bringing to replacement of an oil layer from gaps in bearings) and withdrawal of oil from gaps of bearings (owing to too their big size, wear of the oil pump or excessively high turns of the engine). Passableness violation маслотоков which the rassovmeshcheniye of oil openings of loose leaves and beds more often result, also conducts to oil starvation and an exit of bearings out of operation. When the reason of malfunctions of bearings is the lack of greasing, the soft blanket of loose leaves is usually forced out from a steel substrate. Sometimes the temperature raises to such values that the substrate gets a bluish shade.

Essential influence on service life of bearings is rendered also by a driving manner. Complete opening of a zaslonka at movement with small speeds leads to substantial increase of load of bearings that conducts to squeezing of an oil film from gaps. Such overloads lead to a strong flexure of loose leaves and education on them thin cracks (fatigue tension). Over time there is a separation of separate slices of a soft layer of the loose leaf from a steel substrate. Car use for movings on short distances conducts to emergence of corrosion of bearings as a result of insufficient warming up of the engine which is at the bottom of formation of condensate and aggressive gases. These products accumulate in impellent oil, forming acids and шлам. When such oil gets to bearings, acid starts to corrode their surfaces, leading to material corrosion.

Incorrect installation of bearings in the course of engine assembly also can lead to a fast exit them out of operation. Pulling of bearings is at the bottom of installation of insufficient size of gaps and, as a result, conducts to oil starvation of bearings. Hit between a back of the loose leaf and a bed of the bearing of extraneous particles at installation of bearings conducts to formation of eminences of a bearing surface that late becomes the reason of an exit of the bearing out of operation.