Update: this is a great conversation. I'll share the relevant parts again when he gets home from school. I think he's going to go for making a video of the saw. Might be just the saw and his voice, not sure how much he'll want to "be a star". He corrected me -- said he didn't think he needs to shorten fuel line. He seems confident that having replaced it the saw will work well once the carb is adjusted. But we'll see if it runs perfect. I know some of the comments here mention the fuel tank vent -- if that's the white plastic piece I think, a new one came with the new carb kit. So I can't see how that's going to be part of any remaining issue. But we'll see how it runs. He tends to work on this on weekends. Funny thing about YouTube. Both he and his brother -- BOTH -- got so inspired by YouTubers that they have walked around the house narrating made-up YouTube videos. When I was his age, or younger, I did imaginary sportscasts of football games. His brother has outgrown it, but there was a time when both were walking around the house at the same time narrating different YouTube videos. One on engines, the other on Minecraft (video game). Neither one of them plays video games much at all, which seems kind of a victory somehow. The 10 yr old does zero video games except Car Mechanic Simulator, which I got last year for $2.99 because it's the 2015 version. We don't do it a lot, but I feel like it's pretty good in some ways. And the car problems they give you keep getting more and more complicated. And you don' t have to spend hours on rusted bolts.