Patent ID: 6471559
Filing Date: 2002-10-29
Classification: B63H,F01N,F01P,F02B,F02F

Abstract:
An outboard motor comprising an internal combustion engine, an exhaust guide plate being positioned generally below said internal combustion engine and comprising an exhaust guide passage, said internal combustion engine comprising a generally vertically extending crankshaft and a cylinder block comprising a first cylinder bank and a second cylinder bank, said first cylinder bank and said second cylinder bank being inclined relative to each another, said first cylinder bank comprising a first lower cylinder and said second cylinder bank comprising a second lower cylinder, a first cylinder head assembly enclosing said first lower cylinder and a second cylinder head assembly enclosing said second lower cylinder, said first cylinder head assembly comprising a first exhaust port and a first exhaust runner corresponding to said first lower cylinder and said second cylinder head assembly comprising a second exhaust port and a second exhaust runner corresponding to said second lower cylinder, said first exhaust runner extending between said first exhaust port and a first generally vertically extending exhaust manifold, said second exhaust runner extending between said second exhaust port and a second generally vertically extending exhaust manifold, a first connecting exhaust conduit communicating with said first exhaust manifold and a second connecting exhaust conduit communicating with said second exhaust manifold, said first connecting exhaust conduit extending toward said cylinder block and joining a first end of a first passage formed within said cylinder block, said second connecting exhaust conduit extending toward said cylinder block and joining a first end of a second passage formed within said cylinder block, said first end of said first passage being disposed vertically higher on said cylinder block than said first end of said second passage, said first and second passages merging within said cylinder block into an exhaust discharge, and said exhaust discharge being coupled to said exhaust guide passage.