Since I have several hot air engines I seal the burners when not in use to avoid evaporation. The first picture shows one just completed with a cap over the wick and a plug in the filler hole, both with an O Ring seal.
The second picture shows my new design for a Venting Filler Plug. The threaded plug has an axial hole drilled to the depth of the threaded portion and then a hole cross drilled to intersect the center hole. When the plug is turned in tight the O ring makes a seal. When in use, the plug is unscrewed a turn so air can enter the tank.
The second picture shows my new design for a Venting Filler Plug. The threaded plug has an axial hole drilled to the depth of the threaded portion and then a hole cross drilled to intersect the center hole. When the plug is turned in tight the O ring makes a seal. When in use, the plug is unscrewed a turn so air can enter the tank.
