Fuel Economy Raising of Alternative Fuel Converted Diesel Engines

As a result of the theoretical research, calculations of the theoretical indicated specific fuel consumption for different methods of conversion of diesel engines to gas were carried out. The traditional method of derating in the conversion of diesel engines to gas by installing additional gaskets between the cylinder head and block was considered and the method of derating due to late intake valve closing was proposed.As a result of in vitro experimental research with different methods of conversion of the Opel X17DTL diesel engine, it was found that using the traditional method of engine derating by installing additional gaskets between the cylinder head and block, the indicated specific consumption increased, on average, by 8–9 %. But with a decrease in the compression ratio of the engine by the proposed method due to late intake valve closing, the experimental value of the indicated specific consumption not only did not increase, but decreased, on average, by 7–8 %. The reduction of the compression ratio of the engine due to late intake valve closing by the proposed method was carried out by changing the shape of the camshaft cams. To this end, the cams of the intake valves were fused and then ground to the desired profile, with which late intake valve closing occurred within the predetermined limits.The results obtained allow optimizing the processes of conversion of diesel engines to gas and reducing the fuel consumption of converted engines, on average, by 15–17 % compared to gas engines converted in a traditional way