Expert: Henry Boyter - 10/16/2005

Question
No, I am not a student. I want to know if I can mix a dilute (aqueous) solution of methanol and ammonia without generating any harmful fumes or acid in my windshield washer reservoir. The book cautions only about putting in isopropanol.

Answer
Here are some online recipes.

http://www.budget101.com/recipes/id182.htm

http://www.newschannel5.com/tott/recipes/hcr.htm

http://www.cdkitchen.com/recipes/recs/609/WindshieldWasher_Fluid61200.shtml

http://www.cfra.com/its-your-money/index.asp

I note that methanol and ammonia are not mentioned together.  In very dilute solution, there should at worse be a minor reaction, but the problem may be that the mix is going to be very corroisve to the paint on your car.  I would stick with one of the isopropanol recipes.  Less chance of odd reactions if you do it wrong, less flammable if you mix it wrong, and less corrosive.

No matter what you do mix outside with plenty of ventilation, no kids, and no dogs.  Add some food coloring so kids know it isn't water.  I personally just wait for the stuff to go on sale and buy the commercial version.  If you mix the homemade stuff wrong, it may cost you a paint job.

The opinions expressed are those of Dr. Boyter and
are provided for informational purposes only and
should not be used as advice.  No warranty or
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