B3R Garage: Fuel Line Upgrade-Old, Modern, & New

     Year ago when the Mad Scientist was young the normal method for installing fuel lines in any and all cars involved hard rubber hose and steel hose clamps. As the years passed much of the rubber hoses were replaced with steel fuel lines. At the current time there is yet another alternative to automotive fuel lines available known simply as AN(Army/Navy).

     Due to pressure issues with common rubber hoses, routing issues with steel fuel lines the 1984 Mercury Capri will be getting a fuel pump to carburetor fuel line upgrade. Currently, the fuel line from the Edelbrock fuel pump pours into a Mr. Gasket adjustable pressure regulator and gauge before actually entering the carburetor.

     Although the paperwork for the stock replacement Edelbrock Fuel Pump states that it should not require a pressure regulator, it produces approximately 7.5-10 lb. of fuel pressure before entering the pump. The issue is caused when the information about the Carburetor (Edelbrock 1406) states it should have no more than 6 lb. of fuel pressure at any given time. Therefore, a pressure regulator was needed to reduce the flow of fuel into the Edelbrock 1406 carburetor.

Unfortunately, the rubber fuel line coming from the pump into the fuel pressure regulator continues to leak due to excessive pressure and weak hose clamps. Therefore the foxbody Capri will be getting an AN -6 fuel line and fitting upgrade from the fuel pump to the carburetor.

Rubber Fuel Lines

Common Issues with Rubber Fuel Lines

Flexible & usually don't keep shape
Can melt if in wrong location
Prone to Leaking

Steel Fuel Lines

Common Issues with Steel Fuel Lines

May kink or break if bent improperly
Old lines have high tenancy to rust
Still requires rubber hose lines depending on application

The Solution-AN hose and Fittings

AN fittings are the perfect solution for leaky fuel lines. There are not prone to leaks, swelling, or rusting. AN fittings and hoses are made out of hydraulic steel braided hoses. When selecting AN fittings and hoses it is important to know that AN -6 and -8 hoses and fittings are generally used for fuel lines where as anything larger AN -12 and up is used for larger applications and smaller (AN -4) is ideally used for brake and transmission lines. 

AN Size

Hose I.D.

Hose O.D.

Thread Size SAE

Thread Size NPT

-6

3/8"

0.547"

9/16-18

3/8-18

-8

1/2"

0.641"

3/4-16

1/2-14

The 1984 Mercury Capri will be receiving an AN -6 fuel line upgrade over the weekend and hopefully will no longer be purging fuel over the intake and improve the idle.