Brigg's site can be frustrating! Don't feel alone, I've spent way too much time trying to find information on their engines myself, and when I did, I couldn't tell you how I did.
Wayne, is there any chance that's a Q instead of a 0 in 280777? That fellow over in another post about a rewind for his Briggs just posted the number 31C707. I did a Google on Briggs and Stratton 31C707 and darned if the information for that engine on Briggs' site didn't show up. So I tried Googling Briggs and Stratton 280777 to see what would happen and the first thing on the list was 28Q777. Maybe it didn't stamp well enough into the sheet metal to see the little squiggle on the Q.
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