Outboard Problems

[Charlie]

I am on a short cruise and am having problems with my outboard. When I started it up after sitting for 6 months it smoked for a few seconds and then cleared up and ran fine. The fuel is 6 months old. After running for an hour it now dies when I go above half throttle. I can get it to rev higher if I pull the choke out. Can anyone offer any suggestions on what to check for problems? It is a Mercury 4 stroke 2005.

[boatman61]

Try fresh fuel... sounds like to much air for the old fuel

[Dulcesuenos]

Was the fuel in use ehtanol free? If not it probably has started phase seperation and as such moisture is present and causing issues with the main jet or other issues.
Suggest emptying gas and new fresh fuel with some additive to help remove moisture, draining bowl will help. If not sounds like something gummed up the carb somehow may need removal and cleaning. Ethanol fuels are only good for around 3-3-4 months before they start seperating and having issues.

[tager]

Don't waste time trying to diagnose a problem until you have fresh gas. If you have ever read Zen and the Art of Motorcycle Maintenance, you understand my approach to fixing engines: unexplainable.

Basically, you need fresh gas, air, and something to start a fire.

So buy some new gas, drain the carb bowl, drain the fuel line, and start a big bonfire. The next morning, close the carb drain screw, prime the carb and fuel line with new fuel, and turn her over. She should run fine now!

If you keep fresh fuel, oil, lower unit lube, zincs, plugs, paint, and a coat of fluid film on your outboard, it should last near forever.

[Therapy]

I vote with the crowd on fuel too.

Please let us know.

If not, stall it with squirted in "Sea Foam", let it sit overnight (or an hour if impatient sort), restart.

Don't be alarmed at the amount of smoke the SeaFoam makes. Run it up and stall it with it wide open.

[doc007]

Ethanol is suspected. In many states you can buy pure gas without the corn. It is nothing but a problem in outboards. No easy fix.

[ATC]

My money is betting it is bad fuel...

[Bash]

Six month old gas, these days, is worse than six year old gas would have been back when we were kids. It just isn't going to run an outboard.

[Charlie]

I agree with everyone on the new gas the problem is that I can't get rid of the old gas. I'm in Kalifornia and the cost for getting rid of it is outrageous. I can't burn it on the beach b/c fires aren't allowed i guess I could get rid of bits at a time anyway here is what happened. I took the dink to buy some fuel stabilizer On the way it started fine and ran fine at full throttle. Stabilizer was expensive so I bought some gas treatment and added a bunch into the tank and it continues to run fine.

Tager what is fluid film?

[cfarrar]

The fuel is 6 months old. After running for an hour it now dies when I go above half throttle.

Charlie,

If fresh fuel and fuel additive fail to solve the problem you should remove the carb, disassemble, and soak it in heavy duty carb cleaner. Scrape off any visible deposits, and blow it out with compressed air. Reassemble. It should run great.

As a preventative, we use Stabil Marine Formula preservative with Ethanol treatment in every tank.

[Therapy]

Originally Posted by Charlie

I agree with everyone on the new gas the problem is that I can't get rid of the old gas. I'm in Kalifornia and the cost for getting rid of it is outrageous. I can't burn it on the beach b/c fires aren't allowed i guess I could get rid of bits at a time anyway here is what happened. I took the dink to buy some fuel stabilizer On the way it started fine and ran fine at full throttle. Stabilizer was expensive so I bought some gas treatment and added a bunch into the tank and it continues to run fine.


?

Good to hear it is running.

We have cars and old gas in the dink can is only a few gallons. I add it to the car tanks and burn it up with all my work driving.

[SvLetitgo]

You can put the gas in your car the small volume will not be an issue we do that every three months. Even if we have some 2 stroke ready mix.

Never been a problem. if the carb is gunk dip it in engine tuner work like a charm

Good luck