Exhaust gas purifying device for an outboard motor

Abstract

An exhaust gas purifying arrangement is provided for an outboard motor for a watercraft. At least one exhaust port is provided which opens into a first exhaust passage having a first catalyst member lining at least a portion of its inner wall. The first exhaust passage then opens into an exhaust expansion chamber. Next, a second exhaust passage originates just beyond the expansion chamber. A second catalyst member is mounted within and across a section of exhaust passage beyond the first exhaust passage and at a location above the water line within which the outboard motor operates. A first passageway is provided which leads from the second exhaust passage, from a position beyond the second catalyst member, to an exhaust outlet located at a position below a body of water in which the watercraft operates. And a second passageway leads from the second exhaust passage, also from a position beyond the second catalyst member, to an exhaust outlet located at a position above the body of water in which the watercraft operates. The catalyzer system of the invention is particularly useful for the treating of exhaust gases without introducing undesirable restrictions to exhaust gas flow.

Dependencies are inferred from the claim text.