Although my engine has had preserving oil sprayed into each cylinder, and has been sealed up since leaving the Lycoming factory, I was advised by my LAME cousin to fit dessicant tubes to each of the cylinder heads to suck out any moisture that might be present.
These are simply small little tubes with a threaded end that screws in to the spark plug holes. I fitted one to the top of each cylinder.
These tubes are filled with silica-gel crystals which, when completely dry are a very bright blue colour. As they soak up moisture however, they turn a pale pink colour. Before installing I disassembled each tube, put the crystals onto a small tin tray, and dried them out on top of my wood heater.
The pictures below show the dried crystals installed to the top of cylinders 2 and 4. Hopefully they stay bright blue.
Dessicant tubes installed in all top spark plug holes
Bright blue means nice and dry. Pink means moisture.
