PLEASE!!!!!!!!!!!!!! Do not use that damned WD crap in a perfectly good model engine unless you do it just before you run it. DO NOT use it for after-run oil. In fact, just give it to a neighbor you don't like or use it to loosen up rusty bolts. (It doesn't do much for them either.)

WD-40, if left on ferris metal parts, will cause corrosion since it is chloride based. This comes directly from my local FAA Inspector. It was demonstrated to him when he attended a corrosion seminar a few years ago.

If you want to use some type of spray lube, use something like LPS 1 or Tri-Flow.

Tony