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Why is my weedwacker smoking?

The model # is 316.791940. It's a 4-cycle Craftsman gas trimmer. I had just placed a new spark plug, fresh fuel & oil in after taking it out of winter storage. I was not able to put the exact amount of oil in as I misplaced the original oil container (I measured out 3 oz. from a 20 oz. bottle). At first, I couldn't get it to start & when I did, it started to emit bluish smoke from the back. The only time it stopped smoking was when I shut it off. I did notice that the spark plug was crooked; even after I straightened it, the machine was still smoking.

Craftsman , Trimmers & Edgers , Kenmore PRO Appliances
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2 Answers from these members:
Michael Davis
Pleas recheck your owners manual. $ cycle engines do not usually have oil mixed with the gas which is customary in 2 cycle engines. No damage, but may have caused an extra amount of carbon and the engine is under powered. Good Luck.
by Michael Davis Earned 182 community points in Craftsman
May 8th, 2010
Answered in 2 hours
0 votes
Lyle W
Blue smoke is caused by oil being burned in the cylinder. If you overfilled the engine with oil, it could be causing this problem. Metallic debris from the crooked spark plug could have damaged the cylinder and/or the rings. This could be allowing oil to enter the cylinder and cause this problem.

See if the smoking will stop if you take some of the oil out. If it does then you can likely continue to use the trimmer normally. If it continues to smoke after removing some of the oil, then you will likely need to replace the trimmer.
by Lyle W Earned 6,475 community points in Craftsman
May 11th, 2010
0 votes
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