Caution: This operation is performed in case of severe engine wear. Significant carbon deposits can occur from wear on rings, pistons, valve guides and engine cylinders. An over-enriched mixture, a high oil level in the crankcase, and the use of low-quality fuels and lubricants lead to the formation of carbon deposits in the combustion chamber. The carbon deposits cause detonation combustion of the fuel, which is accompanied by loud metallic knocks. Black smoke appears in the exhaust gases. To eliminate engine knocking, it is necessary to remove carbon deposits from the combustion chamber.
You can remove carbon deposits without disassembling the engine. To do this, pour 15-20 cm³ of a mixture of 80% kerosene and 20% motor oil into each cylinder of a warmed-up engine. After this, rotate the crankshaft 5-8 revolutions. Start the engine after 10-12 hours for 20-30 minutes. During this time, the softened carbon deposits will burn off. After removing the carbon deposits, be sure to change the engine oil.
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