Hammermechanicman
Lawn Addict
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- Jan 10, 2020
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Twins like that can have a dead cylinder and not be noticeable unless under a load. The dead cylinder can dump raw gas into the muffler and ignite there causing what is called afterburning. Looking at the plugs it is not running lean and the engine is not overheated. Try running it on one cylinder then the other by pulling a plug wire. See if it won't run on one of the cylinders.So the engine still ran without a cylinder sparking? Wouldn't it have a noticeable performance issue? This is a two cylinder..I would imagine that performance would be even worse if they weren't sparking... but could they not be sparking optimal? "Mostly working "? So that there isn't a performance issue, but not burning enough?