Oil pan arrangement for four-cycle outboard motor

An outboard motor comprised of a power head having a powering internal combustion engine and a surrounding protective cowling, said engine being of the V-type and having a cylinder block with a pair of angularly inclined cylinder banks each of which has at least one cylinder bore formed therein, a crankshaft rotatably journaled at one end of said cylinder bores by said cylinder block and rotating about a vertically disposed axis, cylinder heads affixed to the other ends of said cylinder banks and closing said cylinder bores, said cylinder heads being formed with exhaust ports in the outer portions thereof, a drive shaft housing and lower unit depending from said power head and journaling a drive shaft for rotation about a vertically extending axis, said drive shaft being drivingly coupled to said engine crankshaft for driving said drive shaft, a propulsion device driven by said drive shaft for propelling an associated watercraft, an oil tank for said engine disposed in substantial part in the upper end of said drive shaft housing and lower unit, a pair of exhaust systems for delivering exhaust gases from said cylinder head exhaust ports downwardly into an expansion chamber formed in said drive shaft housing, each of said exhaust systems terminating within said expansion chamber at a discharge end that does not extend below said oil tank, said oil tank having a portion that extends transversely between the discharge ends of said exhaust systems but spaced inwardly therefrom so as to minimize heat transfer therebetween.