OMC Stern Drives And Motors 1964-1986 Repair Manual., Page 14Get this manual
FUEL SYSTEM especially well secured and bec shock loads in this as high as 20 25 g's Pg" equals of gravity)
Engine Compartment Ventilation
All motorboats built April 25, 1940 and before August 1, 1980, powered by gasoline engine by fuels having flashpoint of 110 less MUST have the following, which is quoted from Guard publication 1984:
At least two ventilation ducts fitted with cowls or their equivalent for the purpose of properly and efficiently ventilating the bilges of every engine and fuel tank compartmentThere shall be at least one exhaust duct installed so as extend to the lower ortion of the bilge and at least one inta duct installed so us to extend point at least midway to the bilge or at least below the level of the carburetor air intake
ventilation system not Guard regulations, the owner recall the manuf rightO can not recall the manufacturer boats built prior August 1, 1980The required the system in proper operating conditionIn addition the blower requirement the engineMUST be affixed the dashboard the blower must operated four minutes before is the engineThis requirement is made the manufacturer and the is responsible keeping in place and in readable conditionT must yellow and to withstand spray!