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Alternate fuels like LPG and CNG are beneficial in terms of operating cost and emissions as well. They also contribute to reduce CO2 emissions. These gas fuels are known for its problems in engines including wear of parts. Cylinder head valve - seat wear is higher in gas engines. This paper discusses the experimental work on reduction of valve -seat wear in 3 wheeler engine. In the development of new higher power version of the gas engine valve-seat interface wear is observed. Effect of this wear on performance, leak and emissions were studied, qualitative measurements of valve temperatures were studied at different conditions with different fuels. Combustion gas and part temperatures are higher in gas engines. Simulation test cycle is developed for the wear test and various solutions to reduce wear at the valve - seat interface were evaluated. Cost effective solution is implemented with minimum changes in engine.

Development of small air cooled motorcycles is ever challenging due to combination of customer expectation, regulatory requirements and cost factors. Achieving higher performance, emission standards means higher engine and parts operating temperature. Under these changes meeting durability targets at reasonable cost needs good understanding of material, surface treatment and tribological aspects. In this paper some of the surface and process improvements done to reduce wear in engine valves and interface systems is discussed in detail. Design of engine valves shall ensure meeting thermal, mechanical strength requirements, wear and durability targets. Surface treatments, coating, surface finish and also use of special materials in tip, valve stem, seat ensures higher durability; low wear in valve and interfacing parts. During new engine development process verification tests, wear observed in valve stem- guide, valve tip- screw interface.