Properly installed, your fuel system will last a very long time and may never need to be changed. In a hard landing, however, some of its parts may be dislodged and stop working. Here are some common fuel-flow problems and fixes.
> If your engine begins to run lean, check for small pinholes in the fuel-supply line. Check closely wherever here are tight bends in the line, or where it comes ino contact with your model. Leaks commonly occur where the lines pass through the firewall. A better method of installation is to drill small holes in the firewall and use lengths of brass tubes in the holes. You can then slip the fuel lines over the brass tubes to complete the system.
> After a hard landing, the flexible pick-up tube and clunk inside the fuel tank may be forced all the way forward. This often goes unnoticed until the next flight, when the tank stops delivering fuel to the engine in a nose-high altitude. To prevent this, solder a short piece of brass tube to your clunk. This decreases the pick-up tube’s flexibility but still allows it to draw fuel in normal flying attitudes.
> If your engine begins to run erratically, chances are that some debris has gotten into the fuel system and is blocking the carb. It usually finds its way into the fuel tank from your fuel jug, and if it blocks the fuel flow, your engine will die. The easiest way to prevent this is with an in-line fuel filter. You install it just before the carb in the supply line. You can also install a filter in your fuel-pump line so you can fill the tank only with filtered fuel. Add a combination fuel clunk/filter and you’ll have a triple defense against deadsticks.