Abstract: A piston for a diesel internal combustion engine including a crown portion at least partially formed of steel and having a combustion surface with a combustion bowl formed therein is provided. The combustion bowl presents a combustion bowl rim area, and a coating including at least one of a noble metal and a refractory metal is applied to substantially only the combustion bowl rim area. The coating is preferably applied in the areas of the combustion bowl rim area that are in line with the sprays of diesel fuel when the piston is in a top dead center position during operation of the engine.

Abstract: A radial shaft seal, method of installation thereof, and seal assembly are provided. The seal includes a mounting portion and a seal lip having a sealing surface extending between an oil side end and a free air side end. An annular bridge extends from the oil side end to the mounting portion in radially overlying relation with the seal lip. An annular installation lip extends from the free air side end toward an air side of the seal. The installation lip has an inner surface spaced radially outwardly from the sealing surface and has an end portion that diverges radially outwardly toward the air side of the seal. The installation lip engages the shaft to promote the seal lip to slide over the shaft without unfolding the seal lip, and then springs radially outwardly from the shaft to remain out of contact with the shaft during use.

Abstract: A piston ring is provided having a bottom surface, a top surface, an inner diameter surface and at least one running surface. A wear protection coating substantially entirely of cobalt is applied to the at least one running surface to protect the base material of the piston ring. Specifically, during operation of an engine, the more durable cobalt wear resistant coating, not the base material which may be steel or cast iron, is in sliding contact with a cylinder wall. The cobalt coating may be applied through, for example, electrodeposition or plasma spraying.

Abstract: A method of constructing a piston, piston formed thereby, and piston body portions are provided. The method includes providing an upper crown portion at least one annular upper rib depending from the upper combustion wall to a free end having a tapered peak. The method further includes providing a lower crown portion having at least one annular lower rib extending to a free end having a tapered peak. Then, moving the upper crown portion and the lower crown portion toward one another and initiating contact between the upper crown portion and the lower crown portion at their respective tapered peaks. Then, continuing moving the upper crown and the lower crown further toward one another after making initial contact at their respective tapered peaks and forming a friction weld joint between the free ends of the at least one upper rib and the at least one lower rib free end.