I store my glow engines by giving them a spray down of marvel mystery oil, flipping them over a few times to make sure the marvel is well distributed, then put them in a baggie and on the shelf they go. never had any problems in the spring ,....new plugs of course. in the spring take them out of the baggie spray them down with carb cleaner, wipe them off and put them on the plane. I don't like leaving my engines in the plane if stored for a long time. just as important is getting the residual castor oil out of the tanks,.....again a shot of marvel keeps the castor coagulation down . if the tank comes out of the plane easily, take it out in the spring and give it a couple ounces of methanol, swish it around and dump it out and you're ready to go. save the used methanol for mixing break-in fuel..... or throw it your car's gas tank.