The test rig provided study of a diesel engine testing. The rig comprises of a four stroke diesel engine coupled to a rope brake for variable speed or electrical dynamometer. A water cooled brake drum alongwith spring balances, comprises rope brake. For electrical dynamometer water- rheostats is used as loading arrangement. With the help of various measurement provided, the test rig can determine BHP, IHP, mechanical & thermal efficiencies, air fuel ratio, specific fuel consumption and heat balance sheet at various loads