Methods, assemblies and apparatuses are for forming a cooling jacket in a cast part of a marine engine, for example in a cylinder head for the marine engine. A cooling jacket core has a longitudinally elongated first portion that forms a first flow path for conveying cooling fluid through the cast part in a first direction and a longitudinally elongated second portion that forms an opposite, second flow path for conveying cooling fluid through the cast part in an opposite, second direction. At least one bridge integrally supports the first and second portions with respect to each other during casting. At least one plug is configured to fit in the cast part where the bridge was located so as to separate the first and second flow paths from each other while sealing the first and second flow paths from an opposite side of the cast part.

This cooling device for an amphibious vehicle includes: a heat exchanger mounted in the amphibious vehicle; a coolant introduction passage through which cooling air or cooling water can be introduced from the outside to the heat exchanger as a coolant; a cooling air discharge passage through which the cooling air having passed through the heat exchanger can be discharged to a cooling air discharge portion communicating with the outside; and a cooling water discharge passage through which the cooling water having passed through the heat exchanger can be discharged to a cooling water discharge portion communicating with the outside. The cooling air discharge passage and the cooling water discharge passage are formed such that at least the cooling air discharge portion and the cooling water discharge portion are independent of each other.

A water pump for a marine engine includes a drive flange for rotating a drive shaft, a housing having an internal cavity and a removable cap assembly. The removable cap assembly includes a cap lock ring secured to the housing, a cartridge extending into the internal cavity of the housing and an impeller rotatable inside the cartridge. The cap lock ring and cartridge are snap-fit together. The rotatable drive shaft has splines, which mate with a splined portion of an impeller to rotate the impeller. To replace the impeller, an operator twists the cap lock ring off the housing without any tools and pulls the cap assembly away from the housing disengaging the impeller from the drive shaft. A new cap assembly replaces the worn cap assembly.

Methods, assemblies and apparatuses are for forming a cooling jacket in a cast part of a marine engine, for example in a cylinder head for the marine engine. A cooling jacket core comprises a longitudinally elongated first portion that forms a first flow path for conveying cooling fluid through the cast part in a first direction and a longitudinally elongated second portion that forms an opposite, second flow path for conveying cooling fluid through the cast part in an opposite, second direction. At least one bridge integrally supports the first and second portions with respect to each other during casting. At least one plug is configured to fit in the cast part where the bridge was located so as to separate the first and second flow paths from each other while sealing the first and second flow paths from an opposite side of the cast part.

Provided is an engine with a starter valve arranged in a compact space and with a cylinder head having a cooling water passage and a starter valve feeding compressed air to a combustion chamber. The starter valve is arranged parallel in the axial direction to a cylinder while fitted into a sleeve, and a portion of the cooling water passage is formed by the outer surface of the sleeve fitted into a starter valve insertion hole formed in the cylinder head. A starting air passage orthogonal to the axial direction of the starter valve insertion hole is formed in the cylinder head, and a portion of the wall surface of the starting air passage is formed by the end surface on one side of the sleeve.

A seawater cooling system adapted to mitigate salt crystallization in a seawater cooling loop. The system may include a pump operatively connected to the cooling loop and configured to pump seawater through the cooling loop, a temperature sensor operatively connected to the cooling loop and configured to monitor a temperature of the seawater in the cooling loop, and a controller operatively connected to the temperature sensor and to the pump, the controller configured to issue a warning and to increase a speed of the pump if it is determined that the monitored temperature of the seawater exceeds a predetermined threshold temperature.

A seawater cooling system adapted to mitigate salt crystallization in a seawater cooling loop. The system may include a pump operatively connected to the cooling loop and configured to pump seawater through the cooling loop, a temperature sensor operatively connected to the cooling loop and configured to monitor a temperature of the seawater in the cooling loop, and a controller operatively connected to the temperature sensor and to the pump, the controller configured to issue a warning and to increase a speed of the pump if it is determined that the monitored temperature of the seawater exceeds a predetermined threshold temperature.

A cooling system is for a marine engine. The cooling system has a cooling fluid conduit that is configured to convey cooling fluid for cooling at least one component of the marine engine; a strainer disposed in the cooling fluid conduit and configured to strain the cooling fluid; and a quick connector that is manually operable to connect and disconnect the strainer from the cooling fluid conduit.

A marine propulsion system for a marine vessel includes an engine effectuating rotation of an output shaft, multiple batteries configured to power a marine vessel load, and an alternator having a rotor that is driven into rotation by the output shaft and that outputs a charge current to the batteries. The marine propulsion system further includes a control system configured to operate the engine in a propulsion mode and a generator mode. Upon receiving a generator mode command to start the engine in the generator mode, the control system operates the engine in accordance with a set of generator parameters to charge the batteries while a shift system of the marine propulsion system is locked in a neutral position such that the propulsor cannot be engaged and the marine vessel remains stationary.

Apparatuses and methods are for cooling exhaust gas emitted from an internal combustion engine in a marine drive. An upstream exhaust conduit is configured to convey exhaust gas from the internal combustion engine. A cooling jacket is located on the upstream exhaust conduit. A cooling passage is located radially between the upstream exhaust conduit and the cooling jacket. The cooling passage is configured to convey cooling fluid along an outer periphery of the upstream exhaust conduit to a location where the cooling fluid is mixed with the exhaust gas. A downstream exhaust conduit conveys the exhaust gas from the upstream exhaust conduit. An orifice device is configured to radially outwardly spray the cooling fluid from the cooling passage onto an inner radial surface of the downstream exhaust conduit so that the cooling fluid cools the downstream exhaust conduit and mixes with and cools the exhaust gas.