Let's start with that, that the total mileage of the car does not always indicate the actual condition of the most important components and units (engine, transmission, steering elements, attachments, etc.). As for the power plant, in some cases it is necessary to determine the wear of the engine, example, when buying a used car. It is important to understand, that is not always the motor, which is severely worn, must be bad to start and "pull", as well as make noise, knock, etc.. d.
It happens, that there are no obvious problems with startup, traction at first glance is quite acceptable, the unit works smoothly. However, after a few thousand or even hundreds of kilometers, such an engine still gets expensive repairs due to severe wear.
In this article we will talk about that, what signs should be paid attention to during the surface inspection of the internal combustion engine, as well as how to find out the wear of the engine without disassembling it.
Determination of the degree of wear of the motor on indirect signs
First of all, ICE inspection must begin with an analysis of the engine. As already mentioned, normally there are no difficulties when starting, troeniye during work, knocks, noise and other extraneous sounds, vibrations, etc.. d. However, even the presence of certain deviations does not necessarily indicate, that the engine was worn out.
Example, start may be difficult due to malfunctions of the ignition system, problem starter or undercharged battery. Hydrocompensators can also knock on the cold, it is possible, noise emitting rollers and drive bearings, attachments, etc.. d.
If experience is not enough, to pinpoint the source of noise or other causes of failure, then, in the first place, attention should be paid to technical fluids and their condition. The test should start with engine oil. An important indicator is the consumption of oil. If the engine started "eat" oil, at the same time it is necessary to top up approximately 1.0 liters per thousand kilometers, then strong wear of CNG is quite probable (taking into account that, that the motor is dry, no leakage of oil seals and gaskets).
Additionally, you should check the exhaust, as the presence of bluish or blue oil smoke from the exhaust pipe will also indicate the cause of increased oil consumption. At the same time it is necessary to unscrew a cover of an oil filler neck on the started engine. If you can clearly see the smoke, then this is another sign of problems with the piston group and cylinders.
Spark plugs should also be unscrewed, to analyze the scale on the electrodes. In this case, checking the engine and its condition on the spark plugs is reduced to that, that in the presence of serious problems with CHP, the soot will be black, traces of oil can be seen, etc.. d.
All of the above symptoms may indicate this, that the engine has problems with the piston rings, the cylinder walls may be worn. An option is also possible, when oil is consumed as a result, that it is necessary to replace the valve seals (oil caps).
This becomes clear, that in some cases the motor can still be further "revived" with minimal investment (ring trimming or replacement, installation of new oil caps, transition to a more viscous oil), while in others the power unit must be disassembled and overhauled (boring / sleeve block, replacement of pistons, etc.).
Check of piston and connecting rod group of the engine
Naturally, without special equipment, that is, "by eye", the above-described methods of engine wear is difficult to determine. You can detect a problem, but the exact cause can be difficult to establish. Given these features, the next step in the inspection are the most common actions:
- compression measurement;
- measurement of oil pressure in the engine;
Compression is a conditional indicator of the state of the piston group (pistons, piston rings and cylinders), measuring the oil pressure allows you to assess the condition of the connecting rod bearings, crankshaft necks, etc.. d.)
It is important to understand, that compression in an engine depends on many factors and conditions. Example, the decline may be due not only to problems with CHP, the decline may be due not only to problems with CHP, the decline may be due not only to problems with CHP. To be precise, the decline may be due not only to problems with CHP, the decline may be due not only to problems with CHP, the decline may be due not only to problems with CHP.
the decline may be due not only to problems with CHP. the decline may be due not only to problems with CHP, the decline may be due not only to problems with CHP. the decline may be due not only to problems with CHP, the decline may be due not only to problems with CHP.
Manometer For measurement it is connected to an exhaust pipe in the pallet. At the same time it is very important to close other openings and cracks in the pallet as tightly as possible, and in the engine. You will also need to have a special nozzle for the manometer, as well as technical documentation for a specific ICE model.
We also recommend reading the article about it, what signs indicate burnout of timing valves. In this article you will learn about it, how to determine, that the valve burned out, as well as what symptoms indicate it.
Naturally, many small service stations will not perform such an operation. If it is a question of check of a second-hand car before purchase, most likely the seller will also refuse the request to diagnose in this way. As a result, it remains only to perform compression measurements, taking into account all possible errors and various nuances to obtain accurate results.
- If we talk about measuring the oil pressure in the engine, it's a little easier with that, and the method itself allows you to determine the approximate condition of the connecting rod bearings, crankshaft necks, etc.. d. To solve the problem, unscrew the oil pressure sensor, then this place through the adapter the manometer is connected.
It is important to consider, that before the procedure the engine oil must be replaced with fresh, taking into account all the tolerances and recommendations of the engine manufacturer (SAE viscosity, etc.. d.) It is also necessary to install a new oil filter. Before measuring, the engine must be warmed up to operating temperature. After warming up the motor, measurements are made at different crankshaft speeds.
Then the results obtained on the oil pressure are compared with those, which are specified in the technical documentation for a specific engine. The most accurate data is not so important, it is quite possible a certain error on the manometer. The point is, that the wear of the engine and its connecting rod group indicates a significant deviation from the norm (close 15-20 %). If so, then the power unit will soon need expensive repairs.
As a result
so, now you know, how to determine engine wear. Moreover, optimally use more than one, and several methods at once, described above. You can even perform a series of checks at the same time (example, compression measurements are combined with a spark plug test). The main thing, that all operations were performed correctly.
We also recommend reading the article about it, how to measure compression in an engine without instruments (without compressometer). In this article you will learn about the available ways to quickly measure the compression with your own hands to assess the state of the CHP, etc.. d.
Let's add, that although these solutions give only a rough idea of it, in what condition is the motor and what is the degree of wear, with their help you can quickly get useful information, and without disassembling the engine. This can be useful when choosing a car with mileage.
If there is a need to repair the engine, accurately assess his condition only on indirect grounds (loss of traction, knocks, forests) or by measuring oil compression and pressure, not work. In order to know exactly the degree of wear of the engine, it is mandatory to disassemble the power unit. Then the engine is defective, after which further sorting or overhaul of the motor is carried out.