1988 Johnson/Evinrude "CC" 40 thru 55 Models Service Manual, Page 99Get this manual
3Anti-Siphon Valvesafety standards require permanently installed fuel systems to have anti-siphon protection This protection can be afforded in two ways All fuel distribution lines must be secured above the highest fuel level when the boat is in its normal, unloaded, static floating position Each fuel pickup tube must have an anti-siphon valve installedAnti-siphon valves used must have pressure drop of no more than 2.5 inof mercury (Hg) at flow rate of 20 gallons per hourThe following OMC valves meet this requirementPIN 173273 for 516 in 1.0hose PI 173274 for 3 in 1.0hose PIN 173275 forin 0.0copper Fuel Distribution linesminimum inside diameter of in(9,5 mm) is required for V6 and larger engines38 in(9,5 mm) is preferred for V4 and smaller engines, while minimum of 516 in (7,9 mm) is requiredDistribution lines must be USCG Type "A" reinforced neopreneVinyl hose must not be used in permanently installed fuel distribution system5Fuel Distribution Fittingsall fittings must have minimum inside diameter of 114 in(6,4 mm), while32 in(7,1 mm) is preferred6Fuel Filterfuel filters must have pressure drop of no more than 0.4 inof mercury (Hg) at flow rate of 20 gallons per hourThe filter should have minimum filtered area of 200 square inches (1290 cm )OMC Fuel Filter Kit PIN 174176 meets these requirements7Fuel System PrimingOMC Electric Fuel Primer Kit PI 174651 is available for built-in fuel systemsThe kit mounts near the fuel supply and, when activated, fills the fuel distribution lines and engine fuel system for quicker starting OMC Manual Filter Primer Assembly PIN 377381 is available for engines below 120 HP 45C