If engine oil is mixed with your gas, how do you think that it got in there? not from the oil sump. It must be in the gas you're using, ie 2 stroke mixture. Try using a supply of gas from another source.
GB
June 2011
I can answer this question...
Enging Oil was found in the gas of my Briggs and Stratton 28B702, 1154-E1?
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