Eccentric positioning block suitable for quick switching of engine connecting rods in various types

The invention relates to an eccentric positioning block suitable for quick switching of engine connecting rods in various types. The eccentric connecting rod comprises a large head hole positioning block, a cylindrical small head hole positioning block and a positioning plate. An eccentric positioning pin is arranged at the bottom of the large head hole positioning block and sleeved with a positioning hole in the surface of the positioning plate. The large head hole positioning block is of a rhombus structure and is provided with two longitudinal countersunk head through holes and two transverse countersunk head through holes. The positioning plate is provided with two longitudinal threaded holes and two transverse threaded holes. The eccentric positioning pin on the large head hole positioning block can rotate in the positioning hole, and thus the longitudinal countersunk head through holes and the longitudinal threaded holes are coaxial or the transverse countersunk head through holes and the transverse thr