This is an interesting article that i came across that seems to be pretty relevant. Anything above that has to be a 38 fuel line.
Eboot 20 Feet Petrol Fuel Line Hose With 4 Sizes Tubing For
Common fuel line sizes. However it is difficult to clamp with a standard worm gear clamp. Here is a more in depth break down of the differences in the hoses and the biggest reasons why it is important to have the right ones installed. Neoprene with an outer steel braiding is also offered for custom applications. What size fuel line to use for an outboard 516 or 38. Uncover the fuel line so that it is visible and can be reached easily. How to measure a fuel line diameter.
Slide it carefully over the line so that it fits snugly. 6an 38 od 8an 12 od 10an 58 od 12an 34 od 6an 38 od 8an 12 od 10an 58 od 12an 34 od use of 3an and 4an line. On a typical fuel system when all is sized right a good number to see when all is clean is between 14 3 of hg total fuel restriction with about 10 to 2 hg most common in a well designed fuel system. Lots of strange information out on the internet regarding fuel line sizing and it seems like most of the time people run way more diameter fuel line than they need. Do not remove the fuel line or disconnect it. 516 fuel line can be used in up to a 115 hp outboard engine.
Neoprene fuel line is available in 18 inch through 58 inch sizes on bulk rolls with additional 3 foot sections of large 1 12 inch through 2 14 inch sizes available for gas filler neck applications. Place the top of a 14 inch wrench with an open end over the fuel line. Quick reference for an to inch line conversion 6an 38 8an 12 10an 58 12an 34. Typically these 14 and 516 line sizes are in use for low flow or oem systems but are. Popular fuel line sizes.
Gallery of Common Fuel Line Sizes
