I have a masters degree in agricultural engineering. I loved agricultural machines like you do. I have worked as a lecturer at the agricultural engineering department in a university. This is one career opportunity available for agricultural engineers. You can be a trainer in the tractor engineering industry and train students in understanding the parts of the tractor, difference between 4 wheel and two wheel tractors, how they are used, assemble and dissemble tractor. You can work in the design and product development department as a design engineer on identifying improvements to design. Have you heard of the industry 4 technology where manufacturing industries are using the smart technologies such as robots and computer software in manufacturing. You can be a software engineer developing smart machines. This is a very high paying job with lot of scope. This is the future of manufacturing industry.