Oil/Gas on water

[Got A Byte?]

I have a 20hp 69 johnson that runs like a top. However sometimes once I get to my favorite fishing spot I notice fuel/oil on the top of the water. It appears to be coming out of the exhaust.

I checked on iboats.com and it someone said that old motors are inefficient and this is normal.

Is this normal?
Is their anything I can do?

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Got A Byte?

[Surface Tension]

A little is normal.
A lot could mean a few things. Could be the fuel level in the carbs bowl. The float rises up with the fuel level then is shut off as it reaches the proper fuel level. A bad seat or needle will let gas past. You'll then get raw gas running out the carb or a rich mixture that doesn't get burnt will come out the exhaust. Or it could be your high and or low speed mixture is to rich. Its better to be on the rich side but you not to the extent of dripping raw or unburnt gas. I lean engine will run hotter and shorten the life of the motor, and its common to melt a piston of score cylinder walls. A dirty carb is most often the cause of a engine running lean.

[Steve Bakken]

One thing you didn't happen to mention is if you were doing quite a bit of idling at your fishing spot before you shut the motor off. As with any gasoline engine, fuel and air do not mix as well at idle as they do at high rpm's because the velocity of the air/fuel mixture entering the combustion chamber is not high enough to keep all the fuel vaporized and so some of it puddles or re-condenses into big droplets which do not burn as well, so some passes on through without getting burnt up. Now add two cycle oil to this mixture and a small amount can make a big looking mess on the water. So if you do much idling, this is going to be much more noticable on the water's surface. As long as everything else is functioning properly I wouldn't get too concerned.

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Steve @ www.bakkensboatshop.com

[Got A Byte?]

I have a 20hp 69 johnson that runs like a top. However sometimes once I get to my favorite fishing spot I notice fuel/oil on the top of the water. It appears to be coming out of the exhaust.

I checked on iboats.com and it someone said that old motors are inefficient and this is normal.

Is this normal?
Is their anything I can do?

------------------
Got A Byte?