I was given a WeedEater string trimmer recently. I know they're not that good, but it seems to work better than what I got. I don't think it was used that much. Anyway, I mixed up about a gallon of 40:1 gas for it. I have a moody Homelite that takes 50:1, a Ryobi that takes 32:1, and a Ryobi rototiller that also takes 32:1. Would it hurt those engines if I used the 40:1 mixture gas in them?