Abstract: An exhaust system provides an oxygen sensor within a balance tube for use with a marine engine. The balance tube is configured to protect the oxygen sensor from water that infiltrates the exhaust system. The exhaust system further provides a mounting system configured to attach to an engine such that an axial load placed on the exhaust system.

Abstract: An exhaust system provides an oxygen sensor within a balance tube for use with a marine engine. The balance tube is configured to protect the oxygen sensor from water that infiltrates the exhaust system. The exhaust system further provides a mounting system configured to attach to an engine such that an axial load placed on the exhaust system.

Abstract: An internal combustion engine that includes an oil baffle in the oil sump. The internal combustion engine may include a crankcase comprising an oil sump containing an oil reservoir, a crankshaft, and an oil baffle positioned within the oil sump. The crankshaft may be a vertical crankshaft and a first balance shaft may extend upward from the oil baffle. The crankshaft may be positioned within the oil baffle and a drivetrain may, also optionally, be positioned in the oil baffle. The internal combustion engine may be configured such that the oil reservoir has a first oil level when the internal combustion engine is off and a second oil level when the internal combustion engine is running at normal operating conditions. The first oil level is above a floor of the oil baffle. The second oil level may, also, be above the floor of the oil baffle.

Abstract: An internal combustion engine that includes an oil baffle in the oil sump. The internal combustion engine may include a crankcase comprising an oil sump containing an oil reservoir, a crankshaft, and an oil baffle positioned within the oil sump. The crankshaft may be a vertical crankshaft and a first balance shaft may extend upward from the oil baffle. The crankshaft may be positioned within the oil baffle and a drivetrain may, also optionally, be positioned in the oil baffle. The internal combustion engine may be configured such that the oil reservoir has a first oil level when the internal combustion engine is off and a second oil level when the internal combustion engine is running at normal operating conditions. The first oil level is above a floor of the oil baffle. The second oil level may, also, be above the floor of the oil baffle.

Abstract: A balance system for a single cylinder engine is described. The single cylinder engine generates forces, that if left unbalanced, cause significant vibrations or movement to the single cylinder engine and devices driven by the single cylinder engine. The balance shaft includes a primary balance shaft for a first type of forces and at least one secondary balance shaft for a second type of forces. The secondary balance shaft is driven directly by the primary balance shaft. In one example, only one secondary balance shaft may be used, which may leave some forces unbalanced but is more space and cost effective. In another example, two or more secondary balance shafts may be included in a drive chain such that one secondary balance shaft drive the next secondary balance shaft.

Abstract: A venturi insert for a carburetor, and a carburetor, system and apparatus incorporating the same. In one embodiment, the invention is a carburetor for an internal combustion engine comprising: a carburetor body comprising a plurality of throttle bores extending through the carburetor body, and for each of the throttle bores a fuel delivery passage terminating at a sidewall of the throttle bore; an insert comprising a plurality of venturi tubes and a linking member connecting the venturi tubes together, each of the venturi tubes comprising a venturi passage and a fuel port for introducing fuel into the venturi passage; and the insert secured to the carburetor body so that the venturi tubes extend into the throttle bores and the fuel ports are in fluid communication with the fuel delivery passages, and the linking member is in contact with the carburetor body.

Abstract: A venturi insert for a carburetor, and a carburetor, system and apparatus incorporating the same. In one embodiment, the invention is a carburetor for an internal combustion engine comprising: a carburetor body comprising a plurality of throttle bores extending through the carburetor body, and for each of the throttle bores a fuel delivery passage terminating at a sidewall of the throttle bore; an insert comprising a plurality of venturi tubes and a linking member connecting the venturi tubes together, each of the venturi tubes comprising a venturi passage and a fuel port for introducing fuel into the venturi passage; and the insert secured to the carburetor body so that the venturi tubes extend into the throttle bores and the fuel ports are in fluid communication with the fuel delivery passages, and the linking member is in contact with the carburetor body.