Abstract: To provide a structure for stably supporting an engine in which front and rear portions of the engine are elastically supported. A drive pulley of a V-belt type transmission is mounted on an end portion of a crank shaft of the engine. A driven pulley of the V-belt type transmission is mounted to an input shaft of a gear box. The engine and the gear box are separately supported on the body side. A crank case of the engine is supported on the body side through a front side elastic mount and a rear side elastic mount disposed at front and rear portions. A ring bushing is fitted in a front side body mounting portion provided on a front portion of the crank case, and a mount rubber is fitted in a rear side body mounting portion. The front side elastic mount of the front side body mounting portion is higher in hardness than the rear side elastic mount of the rear side body mounting portion.

Abstract: To make an intake apparatus and the inside of a boat body less likely to be contaminated with oil and to make an electric apparatus less likely to suffer from any trouble. A four-cycle engine having a head cover in which a breather exit is formed is carried in a boat body, and an oil storage portion when the boat is capsized is formed from the head cover. An upper face of the head cover is positioned close to and extends along a ceiling of the boat body, and the breather exit is provided above an upper face of oil stored in the head cover when the boat is capsized. A connection portion of the intake apparatus to a breather pipe is disposed below the breather exit. The head cover has a water drain path formed therein which connects to a plug mounting-dismounting hole and is opened to a peripheral face of the head cover rearwardly of the hole with respect to an advancing direction of the boat body. A water drain flow path is formed at a lowermost end portion of a bearing surface for a plug.

Abstract: To provide a structure for stably supporting an engine in which front and rear portions of the engine are elastically supported. A drive pulley of a V-belt type transmission is mounted on an end portion of a crank shaft of the engine. A driven pulley of the V-belt type transmission is mounted to an input shaft of a gear box. The engine and the gear box are separately supported on the body side. A crank case of the engine is supported on the body side through a front side elastic mount and a rear side elastic mount disposed at front and rear portions. A ring bushing is fitted in a front side body mounting portion provided on a front portion of the crank case, and a mount rubber is fitted in a rear side body mounting portion. The front side elastic mount of the front side body mounting portion is higher in hardness than the rear side elastic mount of the rear side body mounting portion.

Abstract: An arrangement for removably attaching a drive shaft of a track belt to an output shaft of a transmission allows the drive shaft to be mounted and removed easily and rapidly with respect to the output shaft. A driving pulley of a V-belt transmission is mounted on the right end of a crankshaft of an engine. A gear box is disposed proximately on the right side of a driven pulley of the transmission. An input shaft of the gear box supports the driven pulley. An input shaft, an idle shaft, and a final shaft are disposed in the gear box. The outer periphery of the output shaft is sealed with a seal. The output shaft is formed as a hollow shaft projecting and opening to one side of the gear box. The inner surface of the hollow output shaft is splined, and one end of the drive shaft is inserted into the hollow portion of the output shaft. Further, splines formed on the outer periphery of the one end of the drive shaft are brought into engagement with the splines formed on the inner surface of the output shaft.

Abstract: A power transmission system for a snowmobile reduces the weight thereof, and allows a streamlined body to be obtained. A drive side pulley of a V-belt transmission is mounted on a right end of a crankshaft of an engine. A gear box is disposed on the right side of a driven side pulley of the V-belt transmission at a position near the driven side pulley. The driven side pulley is fastened to an input shaft. Thus, the V-belt transmission and gear box are disposed on the same right side of the engine, so that the connecting shaft for connecting the V-belt transmission to the gear box is shortened and the weight thereof is reduced. Further, the V-belt transmission and the engine are disposed between a pair of right and left main frames, and the gear box is disposed outside of the right main frame, to thereby shorten a distance between the right and left main frames.

Abstract: To provide a pump drive structure capable of making a vehicular width more compact. A drive side pulley of a V-belt transmission is mounted on a right end of a crank shaft provided on an engine. A balancer drive gear is provided on the crank shaft opposite to the drive side pulley in the axial direction. The balancer drive gear is meshed with a balancer driven gear on a balancer shaft disposed in parallel to and directly under the crank shaft. Further, a pump drive gear provided at an axial end of the balancer shaft is meshed with driven gears of pump shafts of the water pump and the oil pump distributed on the front and rear sides of the balancer shaft. Thus, the water and oil pumps are simultaneously driven by the balancer shaft.