If the engine runs poorly or intermittently, check the ignition system and fuel system. If the cause of poor engine performance could not be found, perform a compression test.
Regularly carrying out this check will also allow you to prevent the occurrence of malfunctions in advance.
Order of execution
1. Check engine oil level. Make sure the starter is working properly and the battery is fully charged.
2. Start the engine and warm it up to 80-95°C.
3. Switch off the engine and remove tips of high-voltage wires from spark plugs.
4. Turn out spark plugs.
5. Turn a cranked shaft of the engine.
6. Screw the tip of the compression gauge into the spark plug hole.
7. Fully open the throttle.
8. Turn the engine crankshaft about 4 turns with the starter and determine the compression on the instrument scale. Compression: 1500 kpa Minimum allowable compression: 1400 kpa.
9. Repeat steps 6-8 on the remaining cylinders, making sure that the differential pressure for each of the cylinders is within acceptable limits. Permissible differential pressure in the engine cylinders: 100 kpa.
10. If compression is low in all cylinders, pour a few drops of engine oil through the spark plug holes into the cylinders and repeat steps 6-9.
- If adding oil raises compression, the piston rings may be worn.
- If the compression remains at the same level, the valves may have burned out or the cylinder head gasket may have been damaged.
- Screw in the spark plugs and connect the high voltage wires to them. Spark plug torque: 20–30 Nm