A goof was made: use pure isopropyl alcohol
Dear Bob: R.M. from Overland Park, Kan., asked about adding isopropyl alcohol in lieu of a dry-gas additive. You mentioned that he could use either the 50-percent or the 70-percent solution of isopropyl alcohol.
I recommend that you rethink this advice.
I completely agree that isopropyl alcohol is the preferred substitute for dry gas today, because many — though not all — dry-gas compounds contain methyl alcohol, which can be corrosive. Not so isopropyl alcohol.
But a car owner should never use the isopropyl alcohol sold in drug stores, because these solutions are made with water, and of course we don’t want to add water to our gasoline. A chemical-supply house would be the safest way to obtain pure, high-grade isopropyl alcohol for use in the fuel tank.
Thank you, Bob.
— Rev. J.M., Kansas City, Mo.
A: Don’t thank me, Reverend, thank yourself and others like you for bringing this to my attention. Read on.
Dear Bob: I find it hard to understand why you are advising people to put water in their gas tanks! Don’t you realize that commercial isopropyl-alcohol products have water in them?
A 50-percent solution in a 12-ounce bottle would contain 6 ounces of water. Isn’t the purpose of adding a dry-gas product to remove water from the tank, rather than to add water to it?
Walgreen’s sells a 91-percent solution of isopropyl alcohol, which I imagine would be much better than using a 50-percent solution, as you recommended.
Sincerely,
— R.K., Liberty Lake, Wash.
Dear Bob: In a recent article you said that one could use isopropyl alcohol — rubbing alcohol — to replace commercial dry-gas products.
I thought that alcohol was added to gas to disperse any water that might be present. Rubbing alcohol is 70 percent alcohol, and a good share of the other 30 percent is water.
Wouldn’t adding rubbing alcohol have an adverse effect because of the water it contains? Am I missing something?
Sincerely,
R.H., via e-mail
A: No, you’re not missing something. I goofed! I was careless here: I received an electronic heads-up alert about this subject, and the recommended procedure was exactly as I outlined — mistakenly, as it turns out.
I should have said to use pure isopropyl alcohol (IPA), anhydrous or waterfree, which normally can’t be purchased at a drug store. However, Dick Baumgart of Valvoline research tells me that Wal-Mart sells a 16-ounce container of 99-percent-pure IPA — that’s as close to pure as you can get — for $3.74.
Mr. Baumgart also notes that the products sold in auto stores are 100-percent IPA or methyl alcohol, with nothing added except, in some products, a corrosion inhibitor. Both IPA and methyl alcohol are soluble in water and, while they work differently, both prevent the water in the system from freezing.
IPA additives work by holding some water in solution, then burning it off in the combustion chamber. Methyl-alcohol additives work by drawing the water to the bottom of the tank, out of harm’s way. Fuel-tank sloshing then will permit small amounts to be drawn into the fuel system, where it will burn off.
With near-pure Wal-Mart or pure chemical-house IPA, you won’t be getting the corrosion inhibitor included in many gas-line antifreeze additives. All told, therefore, you gain very little by using these, and probably lose by not having the corrosion inhibitor. My choice: a good IPA additive with corrosion inhibitor.
And with the aches and pains I’ve endured because of all this, feel free to send those leftover bottles of 50-percent rubbing alcohol along to me. Lord knows, I need a good rubdown after all the hassle!
AMERICAN DRIVERS FIGHT BACK
Here’s a tip that will help you get better gas mileage while fighting terrorism and cutting our nation’s dependence on Mideastern oil:
The next time you are shopping for a car or truck, consider buying a diesel-powered vehicle. The U.S. Department of Transportation reports that a diesel is generally much more efficient than a conventional gasoline engine.
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