Cooling arrangement for a snowmobile engine

A cooling arrangement for a snowmobile engine, comprising:

• a cooling water jacket formed inside an engine;
• a heat exchanger for cooling water;
• a water pump for ejecting cooling water;
• and
• a thermostat for controlling supply of the cooling water ejected from the water pump into the engine, so as to cool the engine by circulating the cooling water inside the engine, characterized in that:
• the engine is mounted with its cylinder head at top, and an exhaust manifold is disposed on the front side, with respect to the vehicle's direction of travel, of the cylinder head while an intake manifold is disposed on the rear side, with respect to the vehicle's direction of travel, of the cylinder head;
• the water pump is disposed on the front side, with respect to the vehicle's direction of travel, of cylinder block of the engine, under the exhaust manifold and is coupled to a crankshaft projected from one side wall, with respect to the widthwise direction of the body, of the cylinder block, so that it is driven by the rotational force which is transmitted through a drive belt from a rotational member fitted on one end of the crankshaft;
• a cooling water inlet port for leading cooling water into the cooling water jacket inside the engine is provided on the front side, with respect to the vehicle's direction of travel, of the cylinder block and under the exhaust manifold at a position close to the drive belt;
• a cooling water outlet port through which cooling water is taken out from the interior of the engine is arranged on the engine's side face at a position over and opposite to the drive belt;
• and
• the thermostat is arranged at the cooling water outlet port, at a position downstream with respect to the flow of cooling water.