Dear Tom and Ray: Setting the scene: Six middle-age guys cruising the Caribbean in a 40-foot catamaran, mooring and anchoring at a variety of harbors, bays and coves in the Dutch and French West Antilles, using our dingy and its two-stroke motor to ferry us to and from shore.
When the motor started losing power and occasionally misfiring, the most mechanically savvy member of our group (by day a pediatric ophthalmologist) dismantled it and went right to removing the spark plugs, finding both tips well-fouled with carbon, one more so than the other. He replaced the worst one with a new plug found in the boat's tool kit, but lacking another new plug, he decided to try to clean the buildup on the better of the two fouled plugs.
So, lacking any other solvent but having plenty of ethanol of various flavors on board, he and an assistant (by day an architect) soaked the spark plug in (fairly expensive) vodka for an hour or so, after which it cleaned up quite well. After the plug was replaced, the motor ran as smooth as silk, and with plenty of newfound power.
So, our questions are: Is a vodka soak a reasonable way to clean a fouled spark plug; can one damage the plug this way; is there one brand of vodka that's better suited to this than another; seeing as we were sailing in the Caribbean, should we have used rum instead (there was plenty on board); can this method be translated from a two-stroke dingy motor to an automobile engine; and should we let the marketing department of the vodka brand know about its product's expanded functionality? We are much appreciative of any assistance you can offer.
Your fans -- Joe, Martin, Martin, Frank, Tim and George
Tom: Well, we use nothing but Grey Goose in our shop.
Ray: As you've discovered, guys, alcohol is a wonderful solvent. And it's an excellent way to clean carbon off of spark plugs.
Tom: I would guess that the higher the proof -- hence the greater the alcohol content -- the better it's going to work for you.
Ray: And I would think that alcohols without flavorings or sweeteners would be preferable, because you don't want sugars or syrups gooping up your plugs. So I'd use vodka over, say, Grand Marnier.
Tom: Of course, what you'll find is that the plugs won't stay clean for long. Not because you used vodka to clean them, but because the fouled plugs are a symptom rather than a cause of your problem.
Ray: The real problem is a carburetor that's causing the engine to run too rich, or a weak spark, or something else. But as a temporary fix to keep you going, you guys came up with a perfect solution. And it would work for a car, a boat, a lawn mower or a model airplane.
Tom: What we have to figure out is whether it's more cost-effective than the carburetor cleaner we currently use in the shop. I'll have to compare the cost per ounce.
Ray: Although we also have to consider the reactions of customers when they walk in and see half-empty, open bottles of vodka sitting on our toolboxes.