Dirty carbs

[UMC]

4 stroke yamaha started up running rough this spring (hasn't been run since winterizing in October). New spark plugs didn't do much and brought it in and they worked on the carbs, saying a couple were pretty dirty. Well, paying for 4 hours of labor isn't much fun, so I'm just wondering if someone has a tip on how to avoid this. I run stabil and ring-free in my gas. Mechanics seemed to blame it mostly on the poor gasoline we get nowadays and implied there isn't much you can do. Thanks

[drippinwet]

When was the last time the carbs were cleaned? Could just be a coincident that it was now. It may have been a long time before they were serviced. I cannot imagine stabil not working as everyone uses it.

[wastewaterguru]

Make sure you have a quality fuel filter.....

and I usually double the recommended amount of Stabil in my last tank of the year.

I have never (ever) had a carb issue related to bad gas. The ethanol is known for causing premature failure in rubber hoses and the needle seats...but it's never been an issue for me.

I would guess the carb issue wasn't related to bad gas.

[boatfixer]

4st carbed engines have very small jets. They are susceptable to plugging whatever be the cause. Old gas is also prone to separation and the "heavier" components of the gas can settle. Its not uncommon for me to clean those carbs in the spring.

[UMC]

I just bought the boat last spring (the motor is a 2002). It seems to me they did some similar work on the carbs when I first bought it too, although not this extensive. In respone to the narrow jets, they said one of the jets was almost completely plugged. Thanks for the replies.

[spearchucker]

Don't use gas with ethanol in it any more than you have to. It is fine if you are using it quickly, but I would never store an engine with ethanol gas. It will cause problems even with Stabil or Seafoam.

[UMC]

Yeah, I always use a gas station by my house that advertises "ethanol-free" gas, so unless they're fibbing me, and I've heard of that happening, I haven't ever put gas with ethanol in it.

[delcecchi]

Yeah, I always use a gas station by my house that advertises "ethanol-free" gas, so unless they're fibbing me, and I've heard of that happening, I haven't ever put gas with ethanol in it.

Is the gas from a special pump, or just the regular pumps? All gas sold for on road use in Minnesota has to have ethanol in it, I am almost positive. So the ethanol free "boat gas" has to have a special pump and tank.

[Ice_Fishin07]

Can you use non-oxygenated gas in 4st outboard? I think non oxy gas is supposed to be free of free of ethanol.

[delcecchi]

Can you use non-oxygenated gas in 4st outboard? I think non oxy gas is supposed to be free of free of ethanol.

Sure you can. All motors, even cars and motorcycles, used non-oxy straight gas until the corn farming lobby got the government to mandate ethanol. Now there is talk of going from 10% to 15% or 20%.

[spearchucker]

Yep, unless the pump is specifically marked with a sticker all gas in MN has to have 10% ethanol.

[UMC]

I'm in North Dakota. All of their pumps are ethanol-free at that station, or so they say.

[tonykummrow]

The best way to avoid dirty carbs, or at least reduce the chance is by running them completely dry before winter storage, In my experience mixed gas will hold up better and longer then non mixed gas. Also the oil in the mixed gas will lube things inside the carb such as the float and needle, helping to keep the needle and seat from leaking and keeping the float free moving. Stabill Has been proven to help but is not always going to do its job. and buying stabill from a reputable dealer may also be a better option, as places like wal mart may have had that product sitting around in the back room for 2 years before reaching the shelf.

[kerryd15]

Not sure this is right but on my motorcycle and boat i treat the gas, fog the engine, and if at all possible drain the carb before long storage. i used to have a lot of issues with my motorcycles plugging carbs or just not running right in the spring. I have been draining the carbs in the fall before storage the last 3 yrs without any issues in the spring. I figure if its not sitting in the jets all winter it cant plug them. The carbs that i do this on all have drains on them so I don't have to pull the carb off to do it.

[SkunkedAgain]

and buying stabill from a reputable dealer may also be a better option, as places like wal mart may have had that product sitting around in the back room for 2 years before reaching the shelf.

You may be right, but it just sounds funny to think that a fuel storage fluid doesn't store very well on its own.

[boatfixer]

I really don't think that is an issue.

[UMC]

Mechanic mentioned that they use a little aviation gas when they winterize boats and that seems to help.

[spearchucker]

Stabill Has been proven to help but is not always going to do its job. and buying stabill from a reputable dealer may also be a better option, as places like wal mart may have had that product sitting around in the back room for 2 years before reaching the shelf.

I bet Wal-Mart sells more Stabil than anyone else and has the freshest stock.

[spearchucker]

Mechanic mentioned that they use a little aviation gas when they winterize boats and that seems to help.

That doesn't make any sense. Just don't store with fuel with ethanol and you have solved 90% of the problem. 2 stroke oil as another suggested has stabilization properties as well.

[tonykummrow]

The overall best way to stop todays fuel from clogging a carb is run it dry before winter storage. Some people have ran their carbs empty, and removed fuel line from the carb or carbs and dumped a little oil down the fuel barb located on the carb. it will put oil in the bowl and keep the gaskets and needle (if rubber tipped) from drying out.

[UMC]

Not being real motor savvy - does this mean just disconnect the fuel line and let it run until it dies? Do you leave the fuel line disconnected all winter? What kind of oil do you drop in the carb? Fogging oil?

[tonykummrow]

you can disconnect the fuel line or shut it off if you have that option. no need to leave it disconnected over winter, once the motor dies and will not start with choke, that means your carb is empty with maybe just a little bit of fuel left in the bowl. any kind of oil will work but 2 stroke oil is what I would prefer. put everything back together and your ready for storage. have had a few customers do this with their small engine equipment and none of them have had any problems.