The outboard is an efi 2.7 litre engine ,changed water pump,thermostats,tube bushings at low rpm overheating buzzer sounds water gives off steam.Went looking for the poppet valve found on the starboard block just beneath the last sparkplug a flat triangular aluminium plate removed it there was lots of waxy material built up in one of the openings cleaned it out and back flushed by disconnecting hose above on head and water came out of the hole, the gasket looked as though it covered the holes, is it that type of gasket or should it be just for the sides,and is this the poppet valve and if not is it in the cylinder head (poppet valve)