Troubleshooting 1989 Yamaha 9.9HP Outboard

[romandesign]

I need advice troubleshooting my 1989 Yamaha 9.9HP FT9.9ELF outboard. It won't start. I use it on my Macgregor 26D sailboat so it's not used a lot. It was working fine last year, then I stored it at home in my basement as usual (so no freezing, no winterizing). I put it back on the boat today, changed gear oil and engine oil (and new oil filter), put fresh gas in, and it won't start. Starter works fine, it turns over, but not even a "cough" or smoke, it's not even trying to start. I checked fuel flow and when I squeeze the bulb it squirts through the tubes running through filter and pump, so it's feeding it up to the carburetor. I unscrewed both spark plugs and checked for spark - there are sparks (tiny ones but visible in daylight, I'm not sure how are they supposed to look). Tried another pair of plugs too - no effect. I think the sparks have signs of wetness inside - maybe gas in cylinders? Could it be flooded? There's no movement in the top transparent bulb over the carburetor - is there supposed to be fuel visible on top there? Anyway, what could have happened over 10 months it was stored at home? I'm not sure if I could just drain the carburetor - there is a screw at the bottom, but not sure what it does... Don't want to mess it up worse than it is. It was running fine for 5 years since I got it. I rarely use the boat so it only runs several hours per season. The only thing is after it runs for a while and then sits for a couple of hours, it was difficult to start, but it would always start after a few tries. I did clean the carburetor 2 years ago, replaced the impeller when I got it (5 years ago) and it was fully serviced about 6 years ago by previous owner - everything was shiny new including all the rubber parts when I got it. Still looks good. For now I left plugs unscrewed so if there's gas in cilynders it can evaporate. What would be my next steps?

[romandesign]

OK I solved it, it runs now. I found how to drain the carburetor and that's what did it. Maybe there was some water or stale gas in the carburetor. Once drained, it started right away and run fine and smooth for 30 minutes.

[Be Free]

Roman,
You may already know this but just in case:

The number one reason why a small, carbureted outboard fails to start is bad fuel. The number one cause of bad fuel is ethanol. Always use ethanol free fuel in your outboard. Always drain the carburetor when you plan on storing the engine for more than a few weeks. If you get in the habit of running the carbs dry or draining them you will eliminate most of your starting problems.

[romandesign]

Thanks, good advice, it was definitely bad fuel in the carb...

[Jimmyt]

Glad you've got it running again!

I just want to pile on with Bill regarding ethanol in your gas for engines that don't have a lot of fuel turnover. It will absolutely destroy the fuel system.

I have very low turnover in my boat, so I run gas without ethanol ONLY. At the end of each season, the boat gas goes in the lawn and garden gas can for use. I add Stabil to it when I fill the boat tank.

How lucky for you that draining the carb bowl did the trick. Always good to get an easy win!