Small Engines (Lawn Mowers, etc.): riding mower smokes under load, excessive oil consumption, 10w30

Question
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Followup To
Question -
Hello,
I have a Yard Man riding mower with a B&S 16HP OHV engine (abt 5 yrs old).  The other day it started smoking while mowing the lawn.  It will stop smoking once the blades are disengaged, but will start again after engaging or when going up-hill.

Thanks for any help!
Answer -
Depends on the colour of the smoke.  If it's black smoke when the engine is under load, you need to adjust the high speed mixture screw.  With the engine at full throttle, no load, start the mixture screw at 1 1/2 turns out from lightly seated and turn in until the engine surges.  Then open it 1/4 of a turn.  This should be sufficiently rich.  Then you may need to fine adjust the mixture screw as you start using the tractor.  If you are referring to blue smoke, this indicates excessive oil consumption under load.  This is normal if the engine is overfilled on oil or has a lot of hours on it (it's tired) and would require a rebuild.  Hope this helps.

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The smoke is blue and the oil isn't overfilled, so it looks like a rebuild (sigh).
Is 260 hours a lot for this engine?  I wouldn't expect a rebuild for another couple years, at least.

Answer
260 hours isn't a great amount of hours (500+ is getting high) but various factors affect how quickly an engine will wear.  I recommend you switch to synthetic oil (10W30) and continue using it until you start to foul plugs or it gets low enough on power that you begin to notice it.  My own old, tired mower uses oil but I am going to keep using it until I find something to replace it with.  This will give you time to plan the rebuild.  Hope this helps.