2007 Evinrude E-Tec 75, 90 HP outboards Service Manual, Page 198Get this manual
COOLING SYSTEM OPERATION
OPERATION
Cylinder BlockCylinder Head Cooling
The thermostat is located in the top of the cylinder headA separate pressure valve is positioned in the top of the cylinder block adjacent to the exhaust coverThe thermostat and pressure valve control the flow of water entering the vertical water passages of the cylinder head1 2
EMM and Vapor Separator Cooling
Cooling water is routed through the EMM water cavityCooling of the EMM minimizes the temperatures of internal componentsCooling water is routed to the water inlet fitting of the vapor separator water cavityCooling the vapor separator fuel chamber minimizes fuel vaporizationCooling water from the EMM and vapor separator exits through the overboard indicatorSee HOSE ROUTING AND WATER FLOW DIAGRAM on p192
1Thermostat 2Pressure valve