1994 Johnson 120 looper. Bought it a few weeks ago, hadn't been started in 4+ years and fuel was likely that old. After bypassing a bad safety switch, finally managed to get it started and let it run for a few minutes. Shut it down at that point. Drained the old fuel and put a new in-line fuel filter on it. Used the primer bulb to fill the line and filter back up. Now I can't get the engine to start. It cranks over strong and occasionally hits enough to kick the stater out. I have apparently missed an important step somewhere. Anyone have any idea of what I might have missed?