Is the engine you are using an old Fox 35 or another Fox variety with an RC carb? If it is one of the controline types, you might want to remove the needle valve and blow fuel back thru the spraybar to be sure it is clear. Also, when running on the test stand, you will want to make sure that the fuel tank is at an elevation level with or slightly above the needle valve, but you probably already knew that.

The pickup line from the tank can be a typical clunk type if it is an RC plastic tank, or if you are using a tank constructed specifically built for controline, it will be the line nearest the vee side of the tank.