have a 2005 merc 9.9 el start that the carb keeps getting varnished up. What can i do to slow or prevent this. I use fuel treatment but it only gets started about every 2-3 wks during season and less off season
outboard carb blues
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use only gasoline with no ethanol in it.
http://pure-gas.org/index.jsp?stateprov=KY
Use a stabilizer like StaBil or equivalent. Don't trust the additives that are supposed to work with ethanol since in long term use like yours, it has been shown that they don't work very well.. Add something like SeaFoam as well .. It will get better..
small airports may sell fuel to you as well .. that fuel will be ethanol free..
http://pure-gas.org/index.jsp?stateprov=KY
Use a stabilizer like StaBil or equivalent. Don't trust the additives that are supposed to work with ethanol since in long term use like yours, it has been shown that they don't work very well.. Add something like SeaFoam as well .. It will get better..
small airports may sell fuel to you as well .. that fuel will be ethanol free..
I agree with the above posts.
the seafoam will loosen and eventually clean up the carb, but to prevent it use ethanol free gas, or commonly called clear gas by the distributors....
the clear gas is more expensive, but thats only in relation to the purchase price of ethanol gas... if you compare the actual costs of a sh*tty running motor and having it repaired once or twice a year, and also the peace of mind knowing it will start and run when you want it to, you realize quickly the cost savings is in the clear, ethanol free gas..
the seafoam will loosen and eventually clean up the carb, but to prevent it use ethanol free gas, or commonly called clear gas by the distributors....
the clear gas is more expensive, but thats only in relation to the purchase price of ethanol gas... if you compare the actual costs of a sh*tty running motor and having it repaired once or twice a year, and also the peace of mind knowing it will start and run when you want it to, you realize quickly the cost savings is in the clear, ethanol free gas..
Do you run the motor dry at the end of each day of use. I have a two stroker and do that every time. No issues to date.
As a former dealer, I always told my customers to either shut the fuel line off or disconnect it letting the engine run out of fuel thus no gas remaining in the carb. Now with ethanol whether or not you are using any treatement of some sort to combat the ethanol, it is imperative to let the carb run out of fuel. At the end of the season get rid of the old fuel and start with fresh at the beginning of the next season. If you can find someone selling straight gas, then get that but again this is an oil by product, I urge you to let the engine run out of gas and that will eliminate alot of issues.
crazy dave condon
crazy dave condon
anyone that works on carburetors can tell you this.... disconnecting or shutting of the gas will do little for storing a motor with ethanol fuels because when "you run it out of gas", you are only running the the fuel that is in the carburetor fuel bowl down a little but you are not getting it all out of the bowl... there will also be some more left in the line that may not drain into the carb until the motor is layed on its side.
a little bit of fuel is as bad as a bowl full, and sometimes worse because air mixing with the fuel can cause it to break down faster
storing the motor where its cold so the fuel doesnt deteriorate so fast and using fuel additives with an ethanol stabilizer will slow down the deterioration, but using ethanol gas will minimize any worries....
clear gas will get old as it sets around in a tank after a couple of months. it will lose some of its "power" to ignite properly, but still pass thru the system.
BUT ethanol fuel can deteriorate within days, it will get sticky and separate, and the alcohol content makes it more hydroscopic, which means it will actually suck water from the atmosphere causing it to lose a lot of its "power to ignite" quicker while gumming things up in the process...
a little bit of fuel is as bad as a bowl full, and sometimes worse because air mixing with the fuel can cause it to break down faster
storing the motor where its cold so the fuel doesnt deteriorate so fast and using fuel additives with an ethanol stabilizer will slow down the deterioration, but using ethanol gas will minimize any worries....
clear gas will get old as it sets around in a tank after a couple of months. it will lose some of its "power" to ignite properly, but still pass thru the system.
BUT ethanol fuel can deteriorate within days, it will get sticky and separate, and the alcohol content makes it more hydroscopic, which means it will actually suck water from the atmosphere causing it to lose a lot of its "power to ignite" quicker while gumming things up in the process...
Centerline has it right, just running till the engine dies still leaves a little fuel in the bottom of the carb bowl. Some out boards have a bowl drain. If yours does, open it to drain the fuel out or gunk will form. Stabil makes an ethanol version now that helps quite a bit but if the fuel sits long enough in your carb to evaporate, the varnish and gunk can occur anyway. Drain that fuel bowl and your fuel line if it's gonna sit awhile. Also, two strokes are much less sensitive to the problem due to their jets being larger for a given HP. The tiny little passages in a small 4 stroke plug easily and seafoam won't clean 'em out. You'll have to tear down the carb to get it cleaned out.
Kevin
Kevin
MyYamaha mechanic recommends adding 1 ounce 2 stroke oil to each 3 gallons of gas on my 6 hp 4 stroke,and running it dry by putting open fuel connecter on motor.Says oil helps lube fuel bowl.,seems to work .
oil wil dry out also and a small amount of oil will dry out quicker.... and it wont do anything to stop the ethanol from becoming sticky and seperating... it just adds to the mess and helps carbon up the 4stroke...
the gum deposits that form on the fuel inlet valve seat and in the jets cause immediate problems. but if the motor could be layed/stored in such a position that all the gas drained from the jets, valve seat, fuel pump and fuel line, so the deposits were to form on a part of the bowl that was not being used for anything except fuel capacity, then there would be no problem... until the deposit breaks free from its nesting place and plugs up the jets.... this is a fairly common occurance. the motor runs fine for a little bit after starting it, and then it starts running like crap.... sometimes it cleans up by itself, and sometimes it doesnt.... we just dont ever have that problem with clean non ethanol fuel.
It doesnt matter what you do, or how you do it, as long as you feel like its working for you, but there is no getting around the fact that carburetors dont like stale ethanol fuel.... and it goes stale quickly.
the gum deposits that form on the fuel inlet valve seat and in the jets cause immediate problems. but if the motor could be layed/stored in such a position that all the gas drained from the jets, valve seat, fuel pump and fuel line, so the deposits were to form on a part of the bowl that was not being used for anything except fuel capacity, then there would be no problem... until the deposit breaks free from its nesting place and plugs up the jets.... this is a fairly common occurance. the motor runs fine for a little bit after starting it, and then it starts running like crap.... sometimes it cleans up by itself, and sometimes it doesnt.... we just dont ever have that problem with clean non ethanol fuel.
It doesnt matter what you do, or how you do it, as long as you feel like its working for you, but there is no getting around the fact that carburetors dont like stale ethanol fuel.... and it goes stale quickly.
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2 cycle oil does give fuel better stability, but all the above is true. Run ethanol free gasoline if at all possible, and use sta-bil. If ethanol free isn't around, use the ethanol version of sta-bil and try and drain and/or burn off as much as possible from the motor after shut down/hose disconnect.
YOu are correct centerline about ethanol which I saw coming when first mentioned in the late 80's/ I hope you are also fogging oil to the engine when laying up for the winter months.
Some engines will actually get all the fuel out of the carb but again depends on the engne. However, as you said what works, go with that. And again thank you for advising to go with straight gas if you can find it because that corn crap or ethanol as it is called does not really help.
Some engines will actually get all the fuel out of the carb but again depends on the engne. However, as you said what works, go with that. And again thank you for advising to go with straight gas if you can find it because that corn crap or ethanol as it is called does not really help.
I've been using marine Stabil (blue) for the past year with great results. This is speaking from experience after having to replace my carburetor due to gas gumming the old one up (was using "regular" Stabil).
If you're going to put the boat in storage, I'd run the motor dry, then remove the bowl and wipe it dry. I ran my bowl dry last year and still ended up with a corrosion in the bottom of the bowl.
If you're going to put the boat in storage, I'd run the motor dry, then remove the bowl and wipe it dry. I ran my bowl dry last year and still ended up with a corrosion in the bottom of the bowl.
OBTW, forgot to mention that I use the marine Stabil for all my small motors (like the riding lawn mower...had to rebuild that carburetor, too). Living on the coast of Mississippi, the humidity plays havoc with small engines that don't turn over fuel very fast, or when you set metal up that's not protected.
Seafoam
Try using seafoam in every gallon of gas you use and it does keep the carb much cleaner for sure.
Nick
Try using seafoam in every gallon of gas you use and it does keep the carb much cleaner for sure.
Nick
Our small engine shop says to use the mid range gasoline with the Starbrite StarTron fuel treatment. 5 miles at half throttle cleaned up the carb on my Nissan 5hp 4stroke. I added 6 capfulls to a fresh gallon as our mechanic told me and it idles great and starts first pull now after sitting 3 weeks. Marine Stabil and regular gas gummed up my carb so bad it would not idle at all. In two years. It is also supposed to keep gasoline good for 2 years but I wouldn't know about that. Good luck with yours, Charles
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