Methods for reducing oil sticking on surfaces of internal combustion engines

An intake valve assembly provided in an internal combustion engine that includes an engine block with a piston cylinder, a piston moveable in reciprocal motion within the piston cylinder, a cylinder head mounted on the engine block, and an intake conduit mounted to the cylinder head, wherein the engine block, the cylinder head, and the piston define a combustion chamber, the intake valve assembly comprising:

• an intake valve port defined by the cylinder head,
• wherein the intake valve port is in fluid communication with the intake conduit and with the combustion chamber;
• an intake valve mounted in reciprocally movable fashion to the cylinder head for selectively placing the intake valve port in fluid communication with the combustion chamber;
• a first oleophobic coating provided on one or more portions of the intake valve port,
• wherein the one or more portions of the intake valve port include one or more surfaces that provide, with the first oleophobic coating, a maximum static contact angle that is greater than one-hundred degrees for oil and a minimum sliding angle that is less than ten degrees for the oil, and
• wherein the first oleophobic coating provided on the one or more portions of the intake valve port causes the oil on the one or more portions of the intake valve port to atomize into smaller droplets or beads upon contact with the one or more portions of the intake valve port;
• and
• a valve seat insert secured to the cylinder head near an outlet end of the intake valve port,
• wherein the valve seat insert includes a valve seat surface for contacting the intake valve when the intake valve is in a closed position,
• wherein the valve seat insert defines an oil passage in fluid communication with an oil supply conduit and the intake valve port, and
• wherein the oil is to be introduced into the combustion chamber by pumping the oil through the oil passage.

A machine, comprising:

• an engine block for an internal combustion engine,
• wherein the engine block includes a piston cylinder;
• a piston moveable in reciprocal motion within the piston cylinder;
• a cylinder head mounted on the engine block,
• wherein the engine block, the cylinder head, and the piston define a combustion chamber;
• an intake conduit mounted to the cylinder head;
• an intake valve port defined by the cylinder head,
• wherein the intake valve port is in fluid communication with the intake conduit and with the combustion chamber;
• a first oleophobic coating provided on one or more portions of the intake valve port;
• an intake valve mounted in reciprocally movable fashion to the cylinder head for selectively placing the intake valve port in fluid communication with the combustion chamber;
• a second oleophobic coating provided on one or more portions of the intake valve,
• wherein the one or more portions of the intake valve include one or more surfaces that provide, with the second oleophobic coating, a maximum static contact angle that is greater than one-hundred degrees for oil and a minimum sliding angle that is less than ten degrees for the oil, and
• wherein the second oleophobic coating provided on the one or more portions of the intake valve causes the oil on the one or more portions of the intake valve to atomize into smaller droplets or beads upon contact with the one or more portions of the intake valve;
• and
• a valve seat insert secured to the cylinder head near an outlet end of the intake valve port,
• wherein the valve seat insert includes a valve seat surface for contacting the intake valve when the intake valve is in a closed position,
• wherein the valve seat insert defines an oil passage in fluid communication with an oil supply conduit and the intake valve port, and
• wherein the oil is to be introduced into the combustion chamber by pumping the oil through the oil passage.