BB for SB...Your opinions please.

Since you asked, i'm gonna agree with Jim Lusk. I've torn down a few propane engines years ago and most were spotless in the crankcase, pistons and ports. From the pics your engine doesn't look even close to the ones i've seen. I wonder if decent maintenance was done over it's lifespan? Not that anything is wrong with it, just not what i would expect from a propane engine. It definetely has value, but probably the same as any other 440 with that many miles. I agree, shop it around and see what feedback you get. You could always try to hang onto it for next winter? Good Luck.