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Check the compression pressure

To check the compression pressure will need assistance assistant.

Measurement of compression pressure allows an overview of the current state of internal engine components such as cylinder head gasket, valve train components, pistons and piston rings. Analysis of the test results to determine whether the engine is in need of major refurbishment, and only enough to replace the cylinder head gasket. The measurement is made using the compression tester.

PERFORMANCE ORDER

Warm up the engine to normal operating temperature (80 deg.) And stop it. Make sure in the fullness of battery charge and relieve the pressure in the supply system (see. Section Dropping the pressure in the supply). After depressurization not connect wiring of the fuel pump to the end of the scan compression pressure. Remove all spark plugs (see. Section Replacing the spark plug), and connect the tachometer or turn in the appropriate mode device Consult-II. Cook Compression and screw it into the spark plug hole nozzle of one of the cylinders. It is recommended to use a tapered rubber nozzle with a diameter less than 20 mm, so that it is not stuck in the spark plug hole when removed. Fully depress the accelerator pedal and the engine starter motor cranking, count and record the compression tester when they are stabilized. The time of measurement should be as short as possible. Repeat the procedure described in paragraphs 5 and 6 for the remaining cylinders of the engine. Compare the results of the measurement requirements of the Specifications.

Compression in the serviceable engine is growing very fast. Low value shown after the first cycle, increases with subsequent cycles indicates the wear of piston rings. Low value after the first cycle does not increase after the next, indicates a leak through valves or on the punched lining of the cylinder head (can also be the cause of the crack in the head). To decrease the compression may result in the presence of carbon on the valve plates.

The results obtained in the measurement of compression should be approximately the same for all cylinders. If the pressure in any cylinder is at the minimum allowed, and even below, to determine the cause pour into the cylinder through the spark plug hole teaspoon of motor oil and repeat the measurement.

If the addition of oil temporarily improved compression, the cause of its decline, most likely, is the wear of the piston rings or cylinder. If you increase the compression has occurred, it can be assumed that the reason - valve or a leak in a broken head gasket.

Low compression in two next cylinders is almost certainly a result of the breakdown of head gaskets. The presence of coolant in the combustion chamber or in the crankcase will confirm this assumption.

If compression in one cylinder is different from the other more at 1 atm to us, besides the idling speed is unstable, then the reason may be excessive wear of the cam of a camshaft.

After testing, disconnect and set compressometer starred components. Do not forget to dock connector of the fuel pump.