Marine propulsion device internal combustion engine and method for making the same

An internal combustion engine comprising a cylinder block defining a cylinder having an exhaust port, an exhaust outlet, and an exhaust passage between said exhaust port and said exhaust outlet, an exhaust catalyst apparatus mounted on said cylinder block, said apparatus including a tongue extending into said cylinder block exhaust passage and dividing said cylinder block exhaust passage into an upstream portion communicating with said exhaust port and a downstream portion communicating with said exhaust outlet, and said apparatus including an exhaust passage communicating between said upstream portion and said downstream portion, and a catalyst located in said apparatus exhaust passage.

A method for adding a catalytic apparatus to an internal combustion engine including a cylinder block defining a cylinder having an exhaust port, and defining an exhaust outlet, an exhaust passage between the exhaust port and the exhaust outlet, and a mounting surface having mounted thereon an exhaust cover further defining the exhaust passage, said method comprising the steps of providing a catalytic apparatus including a housing assembly including a tongue and an exhaust passage, removing the exhaust cover, and mounting the housing assembly on the cylinder block mounting surface with the tongue extending into the cylinder block exhaust passage and dividing the cylinder block exhaust passage into an upstream portion communicating with the cylinder exhaust port and with the exhaust passage of the housing assembly, and a downstream portion communicating with the exhaust passage of the housing assembly and the cylinder block exhaust outlet.

An outboard motor comprising a drive shaft housing, a propeller shaft rotatably supported by said drive shaft housing, an internal combustion engine drivingly connected to said propeller shaft, said engine including a cylinder block which is mounted on said drive shaft housing and which defines a cylinder having an exhaust port, and an exhaust catalyst apparatus mounted on said cylinder block externally of said drive shaft housing, said apparatus defining an exhaust inlet communicating with said cylinder block exhaust port, an exhaust outlet, an exhaust passage communicating between said apparatus inlet and said apparatus outlet, and a catalyst located in said apparatus exhaust passage such that substantially all exhaust gases flowing from said exhaust port to the atmosphere flow through said catalyst at all times during engine operation.

An internal combustion engine comprising cylinder block means defining an exhaust inlet and an exhaust outlet, a catalyst housing connected to said cylinder block means, a catalyst supported by said catalyst housing, an exhaust baffle which is connected to said catalyst housing such that said catalyst housing is located between said exhaust baffle and said cylinder block means, and which cooperates with said catalyst housing to define an exhaust passage that communicates between said exhaust outlet and said exhaust inlet and that has therein said catalyst, and a cover which is connected to said exhaust baffle such that said exhaust baffle is located between said cover and said catalyst housing and which cooperates with said exhaust baffle to define a water jacket adjacent said exhaust passage.