gummed carb on yam 9.9 4 stroke

[billy-bobby]

My new 9.9 wouldn't start after sitting for about three months. Service dept fixed it , and said that one of the jets in the carb was gummed from fuel sitting in carb for more than a couple of months. How do I prevent that from happening again when I might not use it for a couple of months or even over winter? What should I do before I put it away for awhile?<br />thanks.

 

[Maximum Gravity]

Re: gummed carb on yam 9.9 4 stroke

Run some type of fuel stabilizer in it - all the time. If you know there will be (or could be) periods of inactivity, add stabilizer with every tank fill up.<br /><br />Gasoline only has a shelf life of 90 days. The smaller the carb and jets, the more prone it is to gumming up.<br /><br />Walmart sells almost a gallon of Stabil for something like $13-$18 - This will get most any small engine through at least one boating season.

 

[Maximum Gravity]

Re: gummed carb on yam 9.9 4 stroke

I missed a part of your question. For winter time, you should use some sort of fogging fluid - usually sprayed down through the carb throat. This help keeps the cylinder walls and rings lubricated as well. Store the motor as close to the straight up and down position as possible. In addition to the fuel stabilizer, this should give pretty good protection against any serious problems.<br /><br />Couple that with lubing up your cables, and a lower unit oil change, (assuming no leaks or bad seals) come spring, you should have a pretty easy go of getting in the water.

 

[Forktail]

Re: gummed carb on yam 9.9 4 stroke

I own 5 of these Yamaha 9.9's (1984-2003). Some of which I have consistently stored 9 months each year. I've never had a problem with carbs gumming up.<br /><br />Yamaha says to unhook the fuel line, run the carberator dry of fuel prior to storage, and put a teaspoon of oil in the cylinders. Works for me. Fogging is not mentioned. <br /><br />According to Chevron, "Gasoline stored in a tightly closed container in a cool place will stay good for at least one year. It is better if the container or gas tank is almost (95%) full. If the container or gas tank will be in the direct sun or will be heated above 80°F much of the time, add an aftermarket fuel stabilizer to the gasoline when you first buy it. Gasoline-oil blends for two-stroke cycle engines stored under the proper conditions will keep as well as gasoline itself."

 

[jim dozier]

Re: gummed carb on yam 9.9 4 stroke

Forktail, while I agree that what you quote is probably factual it may also be misleading. What Chevron is actually saying is that in a full closed container (such as the one you store gas in in your garage), the gas is still "useable" for up to a year. That is fundamentally different than the question here which is basically, if gas is left drying up in my carburetor bowl and jets how long do I have before the evaporating gas turns to varnish forcing me to rebuild the carb. There are probably many extenuating circumstances, but I don't think it is advisable to let a carb sit for a year and expect that 100 out of 100 people who do so will have no problems.

 

[billy-bobby]

Re: gummed carb on yam 9.9 4 stroke

thanks for the comments so far. Here's what the technician told me today: not only should I remove fuel line and run motor to stall, but while I'm doing this, activate the accelerator pump, and after the motor shuts off, I also have to drain gas through drain screw onthe carb. This sounds rather excesssive for putting a motor up for a couple of weeks or more. I feel that if I have to go through this everytime I let the motor stand for more than a couple of weeks then i chose the wrong motor in the first place. Sounds like a lot of maintenance.

 

[Bear]

Re: gummed carb on yam 9.9 4 stroke

Remove fuel line, 2 seconds<br />Run the engine untill i stalls, 60 seconds<br />Remove cowling, 5 seconds<br />Drain the carb, 5 seconds<br />Put the cowling back, 6 seconds<br /><br />Versus removing carb, clean it good, put it back, 3600 seconds. Or take it to the shop, 5 to 10 DAY$? <br /><br />Nah, it isn't that much work, is it? Maybe the first time.<br /><br />If you choose another brand, two stroke, you probably have to do the same thing.<br /><br />After a couple of times it isn't too much hazzle. <br /><br />