Abstract: A method of manufacturing an oil ring is disclosed. The oil ring includes an annular oil ring body having a pair of rail portions at its axially upper and lower portions and butt ends, and a coil expander assembled in the inner periphery of the oil ring body. A number of oil ring bodies and annular spacers having a smaller diameter than the oil ring bodies are stacked, and then aligned and retained using a jig such that an outer periphery of the oil ring bodies becomes a circle. The aligned oil ring bodies are rotated and a flat region that is substantially level with respect to the outer peripheral sliding surface of the plurality of oil ring bodies is formed. Curved regions extending on both sides of that flat region are formed using a buff or an elastic grindstone.

Abstract: An oil ring 1 comprises an annular oil ring body 10 having a pair of rail portions 12 at its axially upper and lower portions and butt ends, and a coil expander 20 assembled in the inner periphery of the oil ring body 10. The cross-sectional profile taken in the radial direction of the outer peripheral sliding surface (f) of the pair of rail portions 12 has a nearly straight region (f1) with a length of equal to or more than 0.05 mm in the center and curved regions (f2) formed on both sides of the straight region (f1).

Abstract: Several embodiments of anti-rotation devices for precluding rotation of the valve actuating lifters or tappet bodies caused by the action of the cam lobe on the engaged surface of the lifter. In each embodiment, the anti-rotation function is achieved without adding to the reciprocating masses of the engine.

Abstract: Several embodiments of anti-rotation devices for precluding rotation of the valve actuating lifters or tappet bodies caused by the action of the cam lobe on the engaged surface of the lifter. In each embodiment, the anti-rotation function is achieved without adding to the reciprocating masses of the engine.

Abstract: Several embodiments of variable valve lift mechanisms employing rocker arms that cooperate with high and low speed cam lobes and which are selectively coupled or uncoupled so as to operate the valve dependent upon either the low speed cam lobe configuration or the high speed cam lobe configuration. The construction is such that there are no bending loads placed on the valve stems and the actuating mechanism is relatively light and can be carried at least in part independently of the rocker arms so as to reduce the reciprocating masses and improve engine performance.

Abstract: Several embodiments of variable valve lift mechanisms employing rocker arms that cooperate with high and low speed cam lobes and which are selectively coupled or uncoupled so as to operate the valve dependent upon either the low speed cam lobe configuration or the high speed cam lobe configuration. The construction is such that there are no bending loads placed on the valve stems and the actuating mechanism is relatively light and can be carried at least in part independently of the rocker arms so as to reduce the reciprocating masses and improve engine performance.

Abstract: A five-valve per cylinder combustion chamber and intake passage arrangement. The side intake passages of the induction system are configured so that the flow exiting them extend toward each other at acute angles and intersect at a point outside of the cylinder bore axis for improving turbulence in the combustion chamber. A fuel injector is also provided which injects fuel only into the side intake passages.

Abstract: An internal combustion engine having a variable valve timing mechanism with a hydraulic control that is mounted on the front of the cylinder head for ease of accessibility and for ease of conversion of the existing engine. The engine includes an oil filter, oil cooler, and coolant pump, which are disposed and driven in a way so as to maintain short flow paths and permit internal conduits to be formed in the engine so as to avoid the possibility of leakage. The variable valve timing mechanism is controlled by hydraulic pressure supplied by the lubricating system, and a control valve assembly is mounted on the cover for the variable valve timing mechanism with the control passages being formed integrally in this cover. In addition, one of the timing chains may be easily accessed for adjustment without removing the cover through the removal of a bolt that holds an accessory mounting bracket to the engine.