Water in the engine

[jsc7]

If you use alcohol, one caution is to not use an off-the-shelf "denatured" alcohol that has denatonium benzoate in it. Denatonium benzoate is a salt and it will not evaporate out, but will remain behind wherever you put the alcohol. This will not be good for the engine.

To avoid it, you can use pure grain alcohol (not available in some states), which is technically known as a "rectified spirit", or you can distill drug store alcohol (which will leave the denaturant behind), or you can use isopropyl alcohol which is often sold with no denaturant.