Abstract: A new working mood of directly using the reciprocating motion of piston for outputting water power is put forward. The unitary design of internal combustion engine and piston pump is accomplished. A sample machine of the internal combustion water power system is made and tested. The working principle and the structural characteristics are introduced. The main working performance in fully load condition is obtained by using the method of computer simulation. The results show that the effective power, the effective thermal efficiency and the output pressure in fully load condition are about 13%～15% higher than the combination system of the internal combustion engine and piston pump, and that the fuel consumption is about 15% lower than the combination system. Using the test method, the fully load characteristics are given. The experimental results are compared with the results of the simulation. The best work area of rotate speed in fully load condition is given.

Key words: Internal combustion engine, Piston pump Fully load characteristics, Simulation Experiment