4.2.2. Capital repairs of the engine - the general information
It is not always easy to define when whether it is required and required to make complete capital repairs of the engine in general. At the decision the whole complex of factors has to be considered.
The big run of the car far not necessarily is the reason for carrying out capital repairs of the engine, also as well as the small run is not 100% a guarantee that overhaul is not required. The most important condition, perhaps, is timely and frequent performing procedures of service of the car. The engine which was exposed to regular and frequent changes of motive oil and the filter, and also other procedures for service of the engine has to work reliably throughout many thousands of kilometers. On the other hand, the neglect procedures of service of the engine can result in need of its capital repairs through very short time.
The excessive consumption of oil indicates the need of paying of attention to a condition of piston rings, saddles of valves and/or the directing plugs of valves. Before coming to conclusion about wear of piston rings or the directing plugs of valves, check whether is the reason of a consumption of oil of its leak. Identification of the reason of the arisen problem will be helped by measurement of compression pressure (see the Part Repair of the engine without its extraction from the car).
Measure oil pressure by means of the manometer installed instead of the oil pressure sensor switch, compare the received value with provided in Specifications. If pressure of oil is not enough, then it can indicate possible wear of radical bearings, bearings of the lower heads of a rod, and/or the oil pump.
Loss of power, uneven operation of the engine, knock or metal noise in the engine, excessive noise during the operation of the valvate mechanism, excessive fuel consumption can also indicate the need carrying out capital repairs of the engine, in particular, if all these signs are shown at the same time. In case carrying out a complete set of procedures of service does not correct a situation, carrying out serious mechanical works can be the only decision.
Capital repairs of the engine mean recovery of characteristics of all internal parts of the engine to specification values of the new engine. At capital repairs of the engine the pro-point of cylinders (if it is necessary) and replacement of pistons and piston rings can be carried out. Usually new radical bearings and bearings of the lower heads of a rod are installed; if necessary the crankshaft for restoration of his necks can be replaced or pierced. Usually surely carrying out recovery work with valves as their state by the time of carrying out capital repairs of the engine is not the best is required. Along with capital repairs of the engine capital repairs of other components such as distributor (if is available), a starter and the generator can be made. Receiving the engine having characteristics of new is result of carrying out capital repairs of the engine. Such engine has to work many kilometers.
When carrying out capital repairs of the engine such critical components of the cooling system as hoses, the thermostat and the water pump have to be also replaced. It is also necessary to carry out a careful inspection of a radiator with the purpose to make sure of lack of obstruction and leaks. Will be to replace with the quite good idea when carrying out capital repairs of the engine the oil pump.
Before starting capital repairs of the engine, attentively read this chapter to prepare themselves for detailed carrying out this work. Capital repairs of the engine are not a difficult procedure in case you carefully follow instructions, will buy the necessary tool and the equipment in the order and pay due attention to all values demanded in Specifications. However carrying out capital repairs of the engine can demand a significant amount of time.
Prepare that the car will appear in a non-working state within at least 2 weeks, in particular, if carrying out engineering works for repair and restoration of its details is required. Make sure available spare parts and the necessary special tool and the equipment. The most part of works can be carried out by means of the ordinary metalwork tool, however for carrying out some measurements whether necessary at decision-making demands separate details of replacement, use of the exact measuring tool will be required. In many cases the dilemma about need of replacement or need of restoration of any detail can be solved only in the conditions of engineering workshops, the corresponding detail has to be examined by qualified specialists.
Always before deciding what procedures of repair or service have to be undertaken in the conditions of engineering workshops, completely disassemble the engine and carefully examine all its components (in particular details of the block of cylinders / case and the crankshaft). Generally the condition of these components is the defining factor at the choice whether the engine has to be subject to capital repairs or the corresponding detail has to be replaced with the new or restored element. However, you do not hurry to buy spare parts or to make small caps repair of other components until they are not carefully examined. Usually the procedure of capital repairs of the engine takes considerable time therefore you should not save and install worn-out or non-standard details in the engine.
In conclusion it is worth noticing that a guarantee of the maximum service life of the engine with the minimum problems after its restoration, is its accurate assembly in the conditions of absolutely pure room.