Re: OIl vapor
Sure its normal, all oil fumes when heated, doesn't mater if it's 10W30 or olive oil. Now as how to quantify how much is normal, no such scale exists. I'd say if your turning your flame arrestor black within a couple of weeks (or less) and you are getting small pools of oil on the intake, then you definitely have a problem, and more than likely to much blow by.
On the flip side, If the arrestor turns a littly oily over the course of a season, and there's a little bit of oil in the lines then that's okay.
