V-engine cooling system particularly for outboard motors and the like

Abstract

An internal combustion engine for an outboard motor includes a cooling passageway extended upwardly through the central core and discharged into a chamber in an exhaust manifold covver between the cylinder banks. The water passes through the cover and to the lateral side edges which have inlets to cooling chambers about the opposite cylinder banks which are continuous and discharge at the uppermost end. The cylinder heads have a cooling chamber with top inlet aligned with the cylinder discharge. The cooling water flows downwardly over to a common discharge header at the lower end for both of the cylinder banks. A pressure relief valve discharges the water from the common header. A separate thermostatic valve is secured to the uppermost end of each of the cylinder banks at the transfer connection from the cylinder cooling chamber to the head cooling chamber and thus at the uppermost and highest point in the two banks. A lower supply chamber is coupled to a pump having a small by-pass opening. The chamber is located at the exhaust pipes and has small ports to spray water into the pipes. Small drains opening from the respective cooling chambers and discharge header drain to the discharge side of the pump for draining of the water from the cooling system through the pump by-pass.