Everything you want to know.... I think Gates is one of the better ones.
Fuel Line Ratings Explained
A common question to our sales team is type of fuel line needed. To maintain a solid stream of fuel minus air and obstructions, use marine grade fuel line components. Think of the fuel line rating system like a report card- A1 is the best! It has the highest fire resistance (2.5 minutes open flame) and lowest permeability making it appropriate for any application. Newest evolution is A1-15, which meets new higher EPA standards for ultra low permeation. The EPA standards became effective Jan 1, 2009, meaning any new boat build with gasoline filled hose in confined areas must use A1-15 hose. At Jamestown Distributors, it's safe to assume any A-1 rated hose sold now is the newer A1-15 type.
Ratings are determined on these two factors, permeability and fire resistance. Particularly with volatile gasoline, permeability is a concern due to vapor build up. If it is in an enclosed space "below deck" it must not give off explosive vapors. Manufacturers often refer to hose as "above deck"/"topside" or "below deck" hose, which is simply a trade gimmick way of phrasing the permeability rating.
The rating system exclusively for marine hose is known as SAE J1527 and it provides for grades as follows:
A1--fuel feed hose; has a fire resistant cover; is designed to have fuel in the hose at all times. Least permeable with highest fire resistance.
A2--fuel vent hose; has a fire resistant cover; is not designed to have fuel in the hose at all times.
B1--fuel feed hose; without fire resistant cover; is designed to have fuel in the hose at all times; intended for non-enclosed spaces. Diesel engines or above deck outboard gasoline applications.
B2--fuel vent hose; without fire resistant cover; is not designed to have fuel in the hose at all times. Diesel vent lines.
If you are building a boat or replacing a deteriorated fuel system, buying 1 coil of A1 hose is often the most useful and safest way to go with less leftover hose in the end.
AWAB clamps are the best choice for complete clamping force to secure fuel hose to barb fittings. A vibration resistant screw and a non-perforated inner surface with rounded edges help this clamp achieve a hose-friendly leak-free seal. Use these clamps in conjunction with brass or stainless steel fuel line fittings to connect tank vents, fuel fill hose, deck fill plates, and fuel feed lines. Any new installation must include a fuel line shut off valve. To achieve maximum performance at higher speeds or engine loads, all fittings selected should maintain adequate ID (internal diameter) throughout the fuel line. If not, the narrow diameter hose will act like a kink in a garden hose; the result is loss of power at wide open throttle. For outboard systems, Sierra offers complete replacement fuel lines to fit Mercury, Johnson, Evinrude, Honda and a host of others. They also offer replacement bulbs and connectors to keep outboard fuel lines primed and running.
