Re: carb cleaner
Bluediamond, you don't mention what kind of engine you have so it's hard to be certain. If you're talking 2-strokes, then Seafoam (deep-creep is the aerosol kind) is a great cleaner. It will clean the carbon out of the combustion chamber, which is something you need to occasionally do with 2-strokes as preventative maintenance depending on how they're rigged. The outboard OEMS; Johnson, Evinrude, Yamaha, Suzuki, Mercury all have their equivalent products under their own labels. Yamaha Ringfree, Mercury Power Tune, BRP Engine Tuner, etc.
You can either spray the stuff down into the engine through the carburetor with the engine running or even the spark plug holes, or mix it with your gasoline. It seems to work better if you directly spray; putting it in your gas is more to keep things clean after you've cleaned it well.
Please note that none of these products are really capable of cleaning a carburetor. That requires disassembly, cleaning all the passages with the aid of carb cleaner (something really noxious which melts rubber and strips paint), and reassembly with a new carburetor repair kit. There isn't a "mechanic in a bottle" that will do that for you.
- technical side:
My take is, naptha for cleaning carbon deposits, isopropyl for mixing any water in the fuel tank with the fuel, and oil to keep up the lubrication.
LATE EDIT: I had forgotten about this one - isopropyl alcohol is the bulk of fuel stabilizers too. They've got some other important stuff that I don't think seafoam has though.