Patent ID: 6575124
Filing Date: 2003-06-10
Classification: B22C,F02B,F02F,F05C

Abstract:
A cylinder block for a multi-cylinder engine, said block comprising a cooling water passage (10) provided at a head side portion of a cast metal inter-bore wall;said cooling water passage (10) comprising a plurality of vertically adjoining transverse water passages (15, 15) provided in vertical and multiple stages; a connecting wall portion (4b) defined by at least one cast metal connecting wall which connects a front half wall portion (4c) of the inter-bore wall (4) to a rear half wall portion (4d) thereof located between the vertically adjoining transverse water passages (15, 15), thereby separating the vertically adjoining transverse water passages (15, 15) from each other; the cooling water passage (10) having its cast metal wall surface which faces a water passage space exposed in its entirety as a molded surface; the cooling water passage (10) further comprising a pair of left and right rising water passages (12, 12) having lower portions provided with cooling water induction portions (13, 13), said transverse water passages (15, 15) communicating the rising water passages (12, 12) with each other so that, cooling water flowing within a left and a right cylinder jacket (8, 8) of the block and introduced into the cooling water induction portions (13, 13) flows into the cooling water passage (10), and thence upwardly out of the block via said rising water passages (12), whereby a head jacket locatable above the block may receive cooling water from the rising water passage (12); a pair of left and right cylinder head tightening boss portions (5, 5) having under surfaces, and which are monolithic with adjacent cylinder walls (3, 3) and located on left and right opposite side portions of the head side portion (4a) of the inter-bore wall (4); and the cooling water induction portions (13, 13) arranged in proximity to the under surfaces of the boss portions (5, 5), said cooling water induction portions extending over a vertical whole area extending from lower edges of the boss portions (5, 5) to the lowest edge portion of the transverse water passage (15) and extending forwardly and rearwardly along adjacent cylinder jackets (8, 8) of the block.