I did not know your engine uses the same aluminum as your window and your window can burn over 300C at over 35,000rpm. Well, I guess we are talking about 2 different type of engines here.
good luck with WD 40 "it will ignite in your engine at the wrong places."
Using WD40 for our 2 stroke engine is NOT ok. It is a "cleaning" agents not just protection. It will cause problem on the piston on our 2 stroke engine so it will surely shorten the life of the engine when you have WD40 inside the engine and when you start the engine with WD 40 inside.
recommendation: If you not using your engine for long time, the "cheapest" way is to disassemble the engine and clean it with WATER using a very soft toothbrush , ( yes water) then dry with hair dryer then use "Tissue paper" to wrap around all the parts. This will stop most of the rusting.
Of course a better way is to use Engine cleaners from Hobby shops, a Alcohol based is better, then put "After run" to the parts and wrap around with Tissue Paper. I have kept engine like these in my warehouse for over 5 years and they don't rust.
Also do not use the plastic cap that came with the engine. They are only good for new engines. Use tissue paper ( they absorb moisture) to cover the opening of your engines.