 printable version
general information
In this part of the Head put descriptions of the procedures for removing and installing the power unit, as well as general overhaul of the cylinder head and internal engine components.
We offer our readers the material contains a wide range of information - from practical advice on the acquisition of the necessary spare parts to the detailed step by step presentation of the execution order of procedures of removal, check the state of repair and installation of the internal components of the engine.
Descriptions of the procedures are based on the assumption that the engine is completely removed from the car and is mounted on a mounting stand or a sturdy workbench. All information pertaining to the repair of the engine, the implementation of which is possible without removing the latter from the car (in situ) are described in Part Engines SOHC and Engines DOHC this Chapter.
Not always easy to determine when there is a need for a major overhaul of the power unit. In the care should be taken a whole lot of different factors.
High mileage is not necessarily a sign that the engine needs major repairs. On the other hand, a short period of operation can not be considered sufficient to guarantee the serviceable condition of the power unit. Perhaps the main factor in determining the life of the engine, is the frequency and regularity of the procedures of general and ongoing maintenance of the car. With normal care engine reliably serve for many, many thousands of kilometers, whereas the negligent attitude to performance of procedures of routine maintenance, coupled with careless driving style can result in having to perform overhaul of the power unit after only a very short time.
Excessive consumption of the engine oil can be regarded as a signal of the need for checking the status of piston rings, valve stem seals and / or valve guides. Naturally, one should first make sure that no oil loss associated with the development of its external leakage. Consult a qualified specialist who will help determine the overall condition of your car's engine on the basis of the test results of the compression pressure in the cylinders (see. Section Checking compression pressure in the cylinders) and measuring the depth of vacuum at various input parameters (see. Section Diagnostics of the engine with gauge).
Loss of power developed, infringement of stability of turns, excessive background noise of the valve mechanism, increased fuel consumption are usually quite characteristic signs of having to perform overhaul of the engine, particularly when these factors are at work. If the execution of the full range of options will not help troubleshoot problems, the only way out is to conduct general mechanical work to rebuild the engine.
Overhaul of the power unit includes the restoration of all of its operating parameters to the level characteristic for the new engine. During overhaul necessarily replacing piston rings and cylinder bores for restoration (groove and / or honing). In the case of the cylinder bore is made the selection of the appropriate oversize pistons. Usually you are replacing main and connecting rod bearing, if necessary, can be made groove and restore the crankshaft journals. Compulsory service is performed valves whose state at the time of the need to perform engine overhaul almost certainly leaves much to be desired. In parallel to the general repair of the power unit is usually performed as the refurbishment of ancillary components such as the starter and alternator. As a result, repair the engine parameters return to the values inherent in the new unit, the latter will be able to reliably serve many more, and many thousands of kilometers.
 | These critical components of the cooling system, as hoses, drive belts, the thermostat and water pump during engine overhaul must necessarily be replaced by new ones. In addition, you should carefully check the condition of the radiator (see chap. System of cooling, heating). In case of signs of leaks or violations patency radiator must also be replaced. Many branded service stations do not give a guarantee for the operation of the restored engine without performing professional cleaning and repair of the radiator. Do not forget to check the condition of the oil pump. |
Before embarking on the overhaul of the engine, carefully read the materials of this part of the chapter for the purpose of theoretical preparation for the work ahead. Note that the overhaul of the engine does not require a high performer training, but takes a lot of time. It is the refusal of the plan to use the car for at least two weeks, especially when the need of recourse to the machine shop to meet the individual recovery. Spend a little marketing, checking for availability of parts required, tools and equipment. In advance, prepare all necessary materials. Most of the work can be performed using a conventional set of plumbing tools, but some tests to determine the suitability of individual components for further use require the use of precision measuring equipment. In case of doubt, ask for help to specialists Car workshop, which will always help you to be defined in the decision on the need for replacement or reconditioning of any internal engine components.
| Before giving any of the parts for reconditioning workshop in the service center, perform a complete disassembly of the engine and all its internal components. Do not forget that the decisive factor in the question of the appropriateness of an engine overhaul is a condition of the block of cylinders it. Often, cheaper and more reliable is to replace the worn out engine restored. Do not proceed with the purchase of replacement components as long as the most carefully examine the state does not block. Remember that time is a major cost factor in carrying out major repairs of the engine, and therefore, it is meaningless to translate it to load or install non-standard parts and components. |
In conclusion, we note that all the efforts to implement the refurbishment of worn components will be wasted by careless attitude to demand observance of cleanliness at the assembly unit.
|
