Since joining the wonderful world of Quarter Scale, IMAA and the Big Birds, I have come to love the gas engines. There are those advocates of large, nitro-burning, 2 cycles, the electrics, etc., but to me there is nothing more thrilling and spine-tingling than the sound and performance of the gasoline 2-cycle engines; the "chain-saw converts" as they may be called.

From my earliest experience with these gnines, I was careful of the fuel. My Dad taught me long ago (with the lawn mowers) to have utmost respect for gasoline. Its volatility and ability to do great damage when uncontrolled are VERY great!

So I never used an electric fuel pump to fill or drain the aircraft on-board tanks. Instead, I used a hand operated pump like the Dave Brown Six-Shooter to fill the tank, and gravity (siphoning) to empty it.

But a fellow IMAA'er, Frank Buz, taught me a better way of fueling -- and with another inexpensive part, I learned a better way of both fueling and defueling with the greatest of ease, safety and convenience.

FUELING: The fueling operation is accomplished through the use of an air pump. Yup! A regular old foot or hand operated air pump, just like you use on your bike. If you don't already have one, Kmart and other stores (hardware, etc.) will normally sell these inexpensive units with adapters for use on other products, like pool rafts, etc. One adapter is nozzle-shaped, like a cone, and may be pushed into the end of your fuel line; any size line.

The method is to pressurize the gas storage tank, forcing gass into your on-board tank. The storage tank has two lines, one vent and one exit. Your on-board tank also has two lines; one vent and one to your carb. By placing a "tee" fitting in your carb line, you can fill and drain the on-board tank most easily. See the diagram.

For the fill operation, since you are pressurizing the storage tank, there is no chance of doing damage to your on-board tank. And with just a few pump strokes you can fill a 16 oz. tank with gas in about one minute.

DEFUELING: The defueling operation is equally simple. And necessary. You don't want to transport or store your model with gas on board. By attaching your pump to the on-board vent line and connecting the carb line (normally plugged) to your storage tank, a couple of pumps will quickly effect the defueling.

One of the neat advantages in using this technique is that you may make important use of the same air pump for charging your on-board retract air tank. My systems all use standard Shrader valves for charging and the tire pump, without the adapter, serves this purpose well.

This technique requires a pump-type carb. If so, it's applicable to any fuel. We hope this info will be of use to you. Happy building and happy flying!