Engine block structure of engine equipped with balancer shaft

PURPOSE: To increase the supporting rigidity of an engine mount by providing a cylindrical balancer housing for storing a balancer shaft, a flange portion to be attached to a transmission case, and reinforcing ribs for connecting the balancer housing to the attaching flange portion. CONSTITUTION: Reinforcing ribs 21, 22 are provided each of which connects a balancer housing 14 to a flange portion 8 extending in the form of a collar from the rear end of an engine block 1, the balancer housing 14 cylindrically extending from the side wall 12 of the engine block 1. The second moment of the cross section of the engine block side wall 12 is therefore increased, and while a transmission case is connected to the engine block 1 in a power plant, the rigidity of the power plant as a whole is secured sufficiently to reduce vibration. Mounting bosses 31, 32, 33 are disposed behind the engine block 1 and are therefore located at the center portion of the power plant, reducing vibration input to the vehicle, etc. COPYRIGHT: (C)1993,JPO&Japio