| abstract |
Fuels for petrol engines, contg. small amounts of phthalic acid diamides of formula (I): In (I) R1 and R2 are alkyl, alkenyl, cycloalkyl or aralkyl, and each pair contains a total of 12-36C. (I) are added in amount of 10-2000(40-300) ppm. Deposits in the carburetter and on valves, esp. when crackcase fumes are recycled to the suction side of the engine, are reduced or removed, preventing changes in fuel/air ratios. |