Its funny how you forget the simple things like that, kind of makes you mad depending on the amount of effort to fix something. My 'simple things' moment of choice: I had just gotten done rebuilding a lawn tractor engine, got it all back together, took lots of time checking everything out, and got it running on the mower. Drove a few laps around the yard, got to the front and it died on me. Went and grabbed a bunch of wrenches, pulled off the hood, started pulling apart the engine and carb. About 10m in, I thought to myself...maybe its out of gas? Sure enough, out of gas. Filled it up, put it all back together, been running great since.