4.7. General and 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 of the Procedure of repair of petrol SOHC engines without extraction them from the car, the Procedure of repair of petrol DOHC engines without their extraction from the car and the Procedure of repair of diesel engines without their extraction from the car 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 and measurements of depth of depression at various initial parameters

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 performance of 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.

Such critical components of the cooling system as hoses, driving belts, the thermostat and the water pump when carrying out capital repairs of the engine HAVE TO be replaced with new without fail. Besides, it is necessary to check attentively a condition of a radiator (see the Head of the Cooling system of the engine, heating of salon and air conditioning). In case of identification of signs of development of leaks or violation of passability the radiator should be replaced also. Many company car repair shops do not give a guarantee for operation of the restored engine without performance of professional cleaning and repair of a radiator. Do not forget to check also a condition of the oil pump (see appropriate sections of Parts of the Procedure of repair of petrol SOHC engines without their extraction from the car, the Procedure of repair of petrol DOHC engines without their extraction from the car and the Procedure of repair of diesel engines without their extraction from the car).

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.

Before giving any of details for carrying out recovery repair to a workshop of car service, carry out full dismantling of the engine and all its internal components. Do not forget that in a question of expediency of performance of capital repairs of the engine the condition of the block of its cylinders is decisive factor. Frequent cheaper and more reliably it appears to replace the worn-out engine restored. Never start acquisition of replaceable components until very carefully do not study a condition of the block. Remember that time is the main expensive factor when performing capital repairs of the engine, and therefore, it is senseless to transfer it to installation of the worked well together or non-standard knots and components.

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.