Abstract: A wet frictional engagement apparatus comprising an input side member, an output side member, a wet friction member attached to one of the input side member and the output side member, an opposite member facing the friction member and attached to the other of the input side member and the output side member, and a device for applying pressure to engage the friction member and the opposite member. The wet friction member comprises a substrate, a plurality of first friction submembers mounted spaced apart on the substrate, and a plurality of second friction submembers mounted on the substrate each adjacent one of the first friction submembers forming a pair of submembers. Each pair of submembers is spaced from each adjacent pair by an oil groove. Each first friction member is relatively less oil-permeable and each second friction member is relatively more oil-permeable.

Abstract: The crankshaft of an internal combustion engine is supported in a split bearing assembly near one end of the crankshaft, with the lower half of the bearing assembly formed in a bearing holder secured to the engine block. An arcuate flange projects axially towards that end of the crankshaft. The flange underlies a crankshaft pulley which drives a timing belt. The arcuate surface of the flange is struck from a center offset from the crankshaft axis in order to provide clearance for the timing belt. The offset construction also improves the joint seal between the oil pan and the engine block.

Abstract: An improved intake manifold structure for internal combustion engines includes a distribution chamber having an upper sub-chamber leading to a carburetor and a lower sub-chamber communicating with the upper sub-chamber through a communication hole. A plurality of branch passages extend from the lower sub-chamber to a plurality of combustion chambers. An air-fuel mixture fed from the carburetor to the distribution chamber is expanded successively in two steps to promote its atomization as it passes through the two sub-chambers, thus improving uniform distribution of the mixture to the respective branch passages. Engine exhaust gas is returned to the upper sub-chamber to further promote the atomization of the mixture.

Abstract: A lubricating system of an internal combustion engine is equipped with intake and exhaust valves and a valve operating mechanism having rotating portions and reciprocating portions. The rotating portions are communicated with an oil pump via a first oil path and the reciprocating portions are also communicated with the oil pump via a second oil path. The rotating portions have a cam shaft in operative connection with a crank shaft. The reciprocating portions include a rocker follower pivoted to a follower shaft and engaging the cam shaft, a rocker arm pivoted to a rocker shaft and operatively connected to the intake or exhaust valve, and a push rod connecting the rocker follower and rocker arm. A series feed oil path is defined in the follower shaft, rocker follower, push rod, rocker arm and rocker shaft so as to pass through their mutual contact portions, and is communicated with the oil pump via the second oil path.

Abstract: A V-type internal combustion engine has a timing gear mechanism positioned in front of the cylinder block for driving the camshaft from the crankshaft. A coolant pump is secured to the cylinder block laterally offset from the crankshaft and adjacent one bank of cylinders. A first discharge passage leads from the coolant pump to the adjacent bank of cylinders and the second discharge passage is formed on a cover for the timing gear mechanism for supplying coolant to the remote bank of cylinders.