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Nissan Maxima QXsince 1993 releaseRepair and operation of the car |
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Nissan Maxima QX + Cars of the Nissan Maxima brand + Maintenance instruction + Settings and routine maintenance - Engine + SOHC engines + DOHC engines - General capital repairs of the engine General information Check of pressure of oil Check of compression pressure in cylinders Diagnostics of a condition of the engine with use of the vacuum gage Alternative versions of schemes of recovery repair of the engine Removal of the power unit from the car - preparation and precautionary measures Removal and installation of the engine Order of dismantling of the engine by preparation it to capital repairs 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 conrod and piston assemblies Removal of a bent shaft Cleaning of the block of the engine Check of a condition of the block Honingovaniye of mirrors of cylinders Check of a condition of components of conrod and piston group Check of a condition of a bent shaft Check of a state and selection of inserts of radical and conrod bearings of a bent shaft Check of a condition of camshafts, pushers of valves and bearings Engine assembly order Installation of piston rings Installation of a bent shaft and check of working gaps of radical bearings Installation of a back epiploon of a bent shaft Installation of conrod and piston assemblies and check of size of working gaps in conrod bearings of a bent shaft Trial start and running in of the engine after capital repairs + Cooling systems, heating + Power supply system and release + Engine electric equipment + Control systems of the engine + Transmission + Coupling and power shafts + Brake system + Suspension bracket and steering + Body + Onboard electric equipment |
General capital repairs of the engine General information Descriptions of procedures of removal and installation of the power unit, and also the general capital repairs of a head of cylinders and internal components of the engine are placed in this Part of the Head.The material brought to attention of readers contains a wide range of information - from a practical advice on acquisition of necessary spare parts, to a detailed step-by-step statement of an order of performing procedures of removal, check of a state, recovery repair and installation of internal components of the engine. Descriptions of procedures are made on the basis of the assumption that the engine is completely removed from the car and is installed on the assembly stand or a strong workbench. All information concerning procedures of repair of the engine which implementation is possible without extraction of the last of the car (in situ) is provided in Parts SOHC Engines and DOHC Engines of the present Chapter. Not always it is possible to define easily the moment when there is a need for carrying out capital repairs of the power unit. In attention the whole set of various factors has to be accepted. The high run at all optional is a sign that the engine needs capital repairs. On the other hand, the insignificant period of operation cannot also be considered a sufficient guarantee of working order of the power unit. Perhaps, the major factor defining engine service life is the frequency and a regularity of performing procedures of the general and routine maintenance of the car. At normal leaving the engine will reliably serve throughout many and many thousands of kilometers of a run whereas the careless relation to performing procedures of routine maintenance together with a negligent manner of driving can be resulted in need of performance of capital repairs of the power unit already later very short term. The excessive consumption of engine oil can be considered a signal of need of conducting check of a condition of piston rings, maslootrazhatelny caps and/or the directing plugs of valves. Naturally, first of all, it is necessary to make sure that losses of oil are not connected with development of its external leaks. Ask for the help the qualified specialist who will help to define the general condition of the engine of your car on the basis of results of check of compression pressure in cylinders (see the Section Check of Compression Pressure in cylinders) and measurements of depth of depression at various initial parameters (see the Section Diagnostics of a Condition of the Engine with use of the vacuum gage). Loss of the developed power, violation of stability of turns, excessive noise background of the valvate mechanism, the increased fuel consumption usually are rather characteristic signs of need of performance of capital repairs of the engine, in particular, when all these factors are shown at the same time. If performance of a full range of settings does not help with elimination of problems, carrying out the general mechanical works on restoration of the engine will be the only way out. Capital repairs of the power unit mean restoration of all its working parameters to the level characteristic of the new engine. During capital repairs replacement of piston rings and restoration of mirrors of cylinders (a pro-point and/or a honingovaniye) is without fail made. In case of performance of a pro-point of cylinders selection of pistons of the corresponding repair size is made. Replacement of radical and conrod bearings is usually carried out, the pro-point and restoration of necks of a bent shaft can be in case of need made. Service of valves which condition at the time of emergence of need for performance of capital repairs of the engine almost for certain leaves much to be desired is without fail carried out. In parallel with carrying out the general repair of the power unit also recovery repair of such auxiliary components as a starter and the generator is usually made. As a result of repair parameters of the engine come back to the values peculiar to the new unit, at the same time the last will be able to serve smoothly still many and many thousands of kilometers of a run.
Before starting performance of capital repairs of the engine, attentively get acquainted with materials of the real Part of the Head for the purpose of theoretical preparation for the forthcoming work. Let's notice that capital repairs of the engine do not demand from the performer of high vocational training at all, however takes away a lot of time. It is necessary to plan refusal of use of the car for the term of not less than two weeks, in particular in need of the request for the help in a mechanical workshop for the purpose of performance of separate recovery work. Carry out small marketing, having checked existence in sale of the required spare parts, tools and the equipment. Beforehand prepare all necessary materials. The most part of works can be executed with use of usual set of the metalwork tool, however some of checks by definition of suitability of separate components to further use demand use of the precision measuring equipment. In doubtful situations ask for the help experts of a workshop of car service who will always help you to be defined with the decision on need of replacement or recovery repair of any internal component of the engine.
In conclusion we will notice that all efforts on performance of recovery repair of worn-out components will be spent for nothing at the negligent relation to the requirement of respect for purity at assembly of the unit. |
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