Abstract: A marine engine exhaust system has an exhaust conduit conveying engine exhaust gas from upstream to downstream, a sensor sensing oxygen content of the exhaust gas in the conduit, and a shield located in the conduit. The shield is configured to shield the sensor from deleterious effects of liquid when liquid and exhaust gas is reverted in the exhaust conduit from downstream to upstream.

Abstract: An apparatus for intake of air to an outboard motor includes an inlet receiving a mixture of air and water from atmosphere surrounding the outboard motor and an outlet discharging the air. A conduit extends between the inlet and the outlet. The conduit has a vertically downwardly oriented first flow path, a vertically upwardly oriented second flow path, and a junction joining the first and second flow paths. The junction is oriented with respect to the first and second flow paths such that both centrifugal and gravitational forces separate the water from the air as the mixture flows therethrough.

Abstract: A fan-jet gas turbine engine heat exchanger is cooled by fan air taken from the fan duct at a relatively high pressure region of the fan nozzle upstream of the fan nozzle's throat and exhausted into a relatively low pressure region of the fan nozzle upstream of the throat. One embodiment provides a cooling air duct with a forward facing scoop at the duct's inlet for capturing cooling air and providing greater dynamic pressure recovery. A diffuser is located upstream of the heat exchanger and a nozzle is located downstream of the heat exchanger with a nozzle exit that forms the cooling duct outlet and an aft facing scoop over the outlet.