I really like the looks of the -III OS engines, with the shiny aluminum case and the black iron fins.
So I impulse-bought a set of four OS 15-III "parts engines" off of eBay last week. I think one is a runner (although it has the wrong prop drive) and at least two of the remaining ones can be made to run.
So -- what's the proper care and treatment of these? I assume I want a high proportion of castor, and probably 20 or 25% oil. What props do they like? What size planes will they pull?
And -- anyone have a stash of prop drives sitting around? There's only two prop drives for the four engines, and none of them are correct (one is steel, forced onto the crank of the "runner", the other is aluminum, too large, equipped with a funky cast-in counterweight, and badly chipped). I may treat this as a chance to learn how to build and wield broaches, but that's crazy-talk when I should just be thinking of getting the engines running.