It's extremely risky to put gasoline in a tank that's been sitting that long, even if it's empty. Use fresh gas from a clean container like an outboard motor gas tank for the initial startup, and clean or replace the onboard tank. There have been numerous instances of engines running well after long periods of storage, and then developing sticky valves, bent pushrods, and even broken rocker arms from gummy deposits formed when gas from the tank dissolved old varnish deposits, which then ended up in the valve guides. It's happened often enough that I believe there's a tech tip here on the site warning about it.
Jerry
