Performance and emission characteristics of a bio-lubricated two-stroke gasoline engine.

Two-stroke petrol engines find wide applications in the areas like chain saws, weed cutters, and power sprayers because of their compactness and higher power to weight ratio. In the present study, the feasibility of using vegetable-based lubricant instead of ordinary mineral 2 T oil is investigated. M15 (85% petrol + 15% methanol) and E15 (85% petrol + 15% ethanol) blend with gasoline are used as the fuel. Experiments were carried out in a two-stroke air-cooled engine equipped with a rope brake dynamometer. It is observed that the vegetable-based lubricant (sunflower oil) is miscible with the tested fuels. The frictional power for the vegetable-based lubricant was found to be less than that of mineral 2 T oil. The brake thermal efficiency improved and the brake-specific fuel consumption decreased for the sunflower oil-based lubricant. The combination of E15 + sunflower oil lubricant exhibited the greatest benefits, raising the brake thermal efficiency by 3.4% and reducing the brake-specific fuel consumption by 1.4%. Hydrocarbon and carbon monoxide emissions were lower for the vegetable-based lubricant than the 2 T mineral oil.