Abstract: A cooling system for a vehicle having a radiator disposed above an engine, and a muffler disposed in a region below the engine. This system includes an air intake guide for guiding cooling air to the radiator from outside, an exhaust guide for guiding a large part of the cooling air having flowed past the radiator, forwardly of the vehicle, a cooling fan for producing air currents flowing from the air intake guide past the radiator to the exhaust guide, and ducts provided for opposite sides of the exhaust guide for guiding part of the cooling air having flowed passed the radiator into a muffler cover enclosing the muffler. The ducts communicate with positions of the muffler cover to blow the cooling air toward connections between exhaust pipes of the engine and the muffler.

Abstract: A working vehicle according to the present invention has a vertical engine mounted in an engine room covered by a hood, cooling air being drawn from above the engine and exhausted outwardly of a vehicle body through exhaust openings formed in a front surface of the hood. The working vehicle includes a fan disposed above the engine, and dust netting disposed above the fan. The dust netting is substantially box-shaped and includes an overhang portion extending rearwardly of the engine and downwardly.

Abstract: A shift adjusting device includes a cam plate and an arm. The cam plate is pivotable and operatively connected to a change speed interlocking mechanism extending between a shift pedal and a belt type stepless change speed device. The arm is also pivotable and operatively connected to a changeover interlocking mechanism extending between a switch lever and a backward/forward drive changeover device. The arm has a pin for engaging a control slot formed in the cam plate. The control slot includes an arcuate forward drive slot portion and an arcuate backward drive slot portion. When the switch lever is in a forward drive position, the pin lies in the forward drive slot portion. The forward drive slot portion allows a full stroke depression of the shift pedal, whereby a forward speed may be selected between minimum speed and maximum speed. When the switch lever is in a backward drive position, the pin lies in the backward drive slot portion.

Abstract: A small riding lawn mower having a grass cutting unit suspended from a body frame between a front axle and a rear axle, an engine supported by a body frame in a position forwardly of the rear axle with respect to a longitudinal direction of the body frame, a hydrostatic transmission disposed rearwardly of the rear axle, and a driver's seat disposed forwardly of the engine. The body frame includes profile members disposed at opposite sides and extending longitudinally of the mower, and a cross plate interconnecting the profile members. A belt transmission mechanism connecting the hydrostatic transmission to an engine output shaft is surrounded by a plate frame structure formed below the body frame. The plate frame structure defines a further independent chamber for accommodating a muffler of the engine. This chamber has peripheral walls shaped to guide cooling air from the engine to the muffler and laterally outwardly of the mower.

Abstract: A rotating rate control apparatus for adjusting rotation of an engine of a working vehicle between a minimum rate and a maximum rate. The control apparatus has a first, a second and a third rotating rate adjusting devices. The first rotating rate adjusting device adjusts a basic rotating rate of the engine between the minimum rate and maximum rate. The second rotating rate adjusting device is shiftable between an ON position and an OFF position. The second rotating rate adjusting device is operable, when in the ON position, to set the engine to a predetermined rotating rate between the minimum rate and the maximum rate inclusive. The third rotating rate adjusting device is operable, when the second rotating rate adjusting device is in the OFF position, to adjust the rotating rate of the engine between the basic rotating rate adjusted by the first rotating rate adjusting device and the maximum rate.

Abstract: A cooling structure for a motor section of a working vehicle with an engine having a vertical output shaft and mounted in an engine hood having an ambient air intake opening defined in an upper surface thereof, and a fan disposed above the engine to draw in cooling air. The cooling air is guided by an air guide cover to flow to a cylinder head and a carburetor attached to a side wall of the cylinder head. The motor section further includes a muffler disposed adjacent and below the carburetor. A muffler cover is disposed between the carburetor and muffler. Part of the air having cooled the carburetor is used to cool an upper surface of the muffler cover. The remaining part of the air having cooled the carburetor is directed under the muffler cover for use in cooling the muffler.

Abstract: An engine speed control system for a working vehicle having an engine, and a propelling transmission and a power takeoff device driven by the engine. Engine speed is adjustable by an accelerator controlled by control signals outputted from a control unit. The control unit is connected to a clutch operation detecting switch for detecting an operative state of a power takeoff clutch for operating a power takeoff device and to a shift condition detecting switch for detecting a shift of the propelling transmission. The control unit outputs a control signal for rotating the engine at an idling speed when the propelling transmission is in neutral and the power takeoff clutch is disengaged, and a control signal for rotating the engine at a high rotating rate when the propelling transmission is in a drive transmitting position or the power takeoff clutch is engaged.

Abstract: A cooling system for a vertical, liquid cooled engine having a first passage for guiding cooling air to a cooling fan disposed above the engine, and a second passage for guiding the cooling air drawn by the cooling fan to flow past the engine and to be exhausted forwardly and downwardly of the engine. The first passage includes an air inlet defined rearwardly of the engine, and is defined by part of an engine hood, a vertical bracket plate erected behind the engine, and a partition extending from the engine hood over an upper surface of the engine. Devices accessory to the engine which are vulnerable to the heat are mounted in a space inside the first passage. The second passage is formed by an air guide cover enveloping the engine and cooling fan and defining an opening in a region opposed to the cooling fan. The air guide cover includes a front portion extending downwardly along the cylinder head.

Abstract: A working vehicle comprising an engine mounted on a vehicle frame, a control box mounted on the vehicle frame, and a radiator erected on the vehicle frame between the engine and the control box structure. A dust-proof space is defined by the control box, the radiator and a hinged hood covering the engine. Elastic sealing elements are arranged between opposite lateral sides of the control box and the radiator, and between an upper end of the radiator and the hood. The hood in a closed position presses upon the upper elastic elements to provide an additional support for the radiator and to seal the dust-proof space.

Abstract: A muffler system for a working vehicle, particularly a lawn mower, comprising a main muffler body connected to an exhaust manifold of the engine, and a curved muffler cover covering the main muffler body from below. An exhaust pipe extends from the main muffler body laterally outwardly of the vehicle body, and defines an exhaust outlet for discharging exhaust gas in a direction away from a front wheel and the ground. Cooling air is blown by a cooling fan from the engine into the muffler cover. The muffler cover defines air exhaust openings for directing the cooling air forwardly of the vehicle body.

Abstract: A wheel drive mode changeover apparatus designed to effect a changeover between (a) a two wheel drive mode having only rear wheels driven, (b) a first four wheel drive mode having front wheels and the rear wheels driven at a substantially equal peripheral speed, and (c) a second four wheel drive mode with the front wheels driven at a higher peripheral speed than the rear wheels. The wheel drive mode changeover apparatus includes a control rod for manually switching between the mode (a) and the mode (b) above. By assuming one position this control rod allows the wheel drive mode changeover apparatus to effect the changeover between the mode (b) and the mode (c) in accordance with a traveling condition of a vehicle.