Patent ID: 6892844

Claim:
A snowmobile comprising: a frame assembly; an internal combustion engine mounted to the frame assembly, the internal combustion engine comprising: a cylinder block defining a cylinder bore; a crankcase connected to the cylinder block defining a crankcase chamber, the crankcase having a crankshaft journaled therein, the crankshaft rotatable about a crankshaft axis; a piston reciprocally positioned in the cylinder bore, the piston driving the crankshaft; and a cooling system having a centrifugal coolant pump, the centrifugal coolant pump located in the crankcase, the centrifugal coolant pump comprising: a lid; a pump case main body, a pump drive shaft journaled in the pump case main body, the pump drive shaft being rotatable about a pump drive shaft axis, a plurality of blades mounted on the pump drive shaft, at least a portion of the drive shaft being interposed between the cylinder block and the lid; a partition member defining at least a portion of a pump chamber inlet port, the partition member and the pump case main body defining a pump chamber configured to house the blades; and a fluid inlet chamber defined by the partition member and the lid, the fluid inlet chamber providing fluid communication between a fluid inlet port and the pump chamber inlet port.