Transmission lubricant system for an outboard motor

An outboard motor comprising:

• an internal combustion engine;
• a driveshaft that is rotated by the internal combustion engine, wherein the driveshaft is disposed in a driveshaft housing;
• a transmission that is operatively connected to the driveshaft, wherein the transmission is disposed in a transmission housing located below the driveshaft housing;
• a set of angle gears that operatively connect the transmission to a propulsor for imparting a propulsive force in a body of water, wherein the set of angle gears are located in a lower gearcase located below the transmission housing;
• and
• a lubrication system that circulates lubricant to from the transmission housing from the gearcase;
• wherein the lubricant system comprises a lubricant circuit and a pump that is configured to pump the lubricant through the lubricant circuit;
• wherein the pump is operatively connected to the driveshaft so that rotation of the driveshaft causes the pump to pump the lubricant;
• wherein the lubricant circuit comprises a lower lubricant cavity and an upper lubricant cavity each within the lower gearcase, wherein the pump circulates the lubricant from the lower lubricant cavity to the upper lubricant cavity;
• wherein the lubricant circuit drains by gravity from the upper lubricant cavity to the lower lubricant cavity;
• and
• wherein the lubricant circuit comprises a plurality of metered holes in the upper lubricant cavity through which the lubricant drains by gravity from the upper lubricant cavity to the lower lubricant cavity.

An outboard motor comprising:

• an internal combustion engine;
• a driveshaft that is rotated by the internal combustion engine, wherein the driveshaft is disposed in a drive shaft housing;
• a transmission that is operatively connected to the driveshaft, wherein the transmission is disposed in a transmission housing located below the driveshaft housing;
• a set of angle gears that operatively connect the transmission to a propulsor for imparting a propulsive force in a body of water, wherein the set of angle gears are located in a lower gearcase located below the transmission housing;
• a lubrication system that circulates lubricant to from the transmission housing from the gearcase;
• wherein the lubricant system comprises a lubricant circuit and a pump that is configured to pump the lubricant through the lubricant circuit;
• wherein the lubricant system further comprises a filter that is configured to filter the lubricant as the lubricant is circulated within the lubricant circuit;
• and
• a bypass valve that opens to allow the lubricant to bypass the filter, wherein the bypass valve is normally closed and is configured to open when the lubricant flowing into the filter exceeds a predetermined pressure.

A lubrication distribution system for lubricating a drivetrain comprising:

• an internal combustion engine and a driveshaft that is rotated by the internal combustion engine;
• a transmission and a transmission output shaft, wherein the transmission operably connects the driveshaft and the transmission output shaft;
• an upper lubricant cavity, a lower lubricant cavity, and a plurality of metered holes, wherein the upper lubricant cavity is located higher than the lower lubricant cavity, and wherein the lubricant drains by gravity from the upper lubricant cavity to the lower lubricant cavity through the plurality of metered holes;
• and
• a pump that pumps the lubricant from the lower lubricant cavity to the transmission to lubricate the transmission, wherein the lubricant drains from the transmission to the upper lubricant cavity.