Patent 7806740 was granted and assigned to Brunswick Corporation on October, 2010 by the United States Patent and Trademark Office.
An oil temperature moderating system of an outboard motor causes cooling water to be warmed to a predefined magnitude of temperature and then conducted through a temperature responsive valve to a coolant conduit, or coolant jacket, in thermal communication with oil within an oil sump of the outboard motor. In this way, the oil within the oil sump is continuously disposed in thermal communication with cooling water that has achieved a temperature controlled by a thermostat or similar device and, as a result, is above the temperature of the water drawn from a body of water in which the outboard motor is operated. This type of system reduces the temperature of oil in the oil sump when it is greater than the cooling water flowing through the thermostat and raises the temperature of oil in the oil sump when it is cooler than water flowing through the thermostat.