Possible water in gas? Old gas?

[modrob]

My 2002 gas coach has been sitting for almost a year (repairs) but I occasionally crank it up and let it run a bit. A couple of weeks ago it started acting up—rough idle, stumbling, etc. Maybe old gas? Maybe some water in it? The motor is a Ford V10. I plan on siphoning out the tank…any other recommendations? Many thanks…

 

[NWIP]

I would suspect old gas but you don’t say where you are located

 

[Kevin D Pem]

Water will only increase when the tank is not sealed. Like NWIP stated, I would question a water problem!

My guess is you are not using stay-bill or sea foam to keep the volitals in the mix. I have been told that sea foam in the gas may help with your problem.

You don't tell us if you let things get to temperature when you exercise the engine. If you don't you could have compromised the spark plugs.

 

[BGMAC]

Kevin is right. The reason you need to operate the engine to operating temperature is to remove moisture from inside the engine. This is a big issue for aircraft engines and there are documents from the aircraft engine manufacturers on how to do this.
The engine draws air from the intake. That air has moisture in it to some degree depending on your location. The oil cavities are also vented and moisture in the air will be in the crank case.
If you run the engine for a short time you won’t put enough heat in the engine to properly evaporate the moisture in the engine.

 

[modrob]

I would suspect old gas but you don’t say where you are located

Southern WV

 

[BGMAC]

Southern WV

My wife is from Parsons WV. It does get humid there. If your gas tank is not full when stored it could get condensation inside the tank from heat and cold.

 

[modrob]

Every time I have started it, I have let it run quite a while…more than enough time to get up to operating temperature…
There are some “canisters” in the front end of the engine compartment that I don’t readily recognize. I’ll have to look into them as well for their functions…I wouldn’t think they’d have anything to do with the fuel system, or maybe so? I’ll get some pics shortly…
(I’ve had to let it sit for so long, due to many other equipment, house, and other family “fixes” that keep popping up)

 

[AbdRahim]

For sitting longer than one month, I always fill the tank and add SeFoam.

You might try adding 2 oz SeaFoam/gal of gasoline in the tank ad see if that helps.

 

[modrob]

My local outdoor equipment dealer suggested the Lucas Fuel Treatment. So I poured some in, let it sit for a little while, then started it up. Ran fine the whole time up to when I shut it off. (about 20 min.)

Now…If I can just get a few other issues taken care of, I just might be able to get it out on the road soon…