Fuel Facts: Water Is Great for Your Plants, Not So Much for Your Fuel System

Sponsored content presented by Sunoco Race Fuels.


Some popular fuel additives promise to remove water—which, thanks to gravity, will settle at the bottom of the tank. The secret ingredient to these magical elixirs? The all-telling safety data sheet, available online, yields the answer: It’s usually methanol—like, often nearly 100% methanol. 

How does methanol help remove water? Science. “When mixing a polar liquid and a nonpolar liquid, they often form two separate phases—like water and oil,” explains Zachary J. Santner, technical specialist at Sunoco Race Fuels. “Sometimes, when you have a high-polarity liquid and a low-polarity liquid that don’t mix, you can add a third, medium-polarity liquid to make all three stay mixed in one phase. Methanol is a medium-polarity liquid when compared to gasoline and water.

So, it acts as a co-solvent,” he continues. This explains how methanol can individually mix with gasoline or water and allow all three to remain in a single phase when mixed.

The result: Methanol will allow the water found in the tank to stay suspended in the gasoline. And an engine can burn a surprising amount of water as long as it stays mixed with gasoline, Santner continues.

The catch? Well, he notes, there are two. 

First, do you really have a problem with water in the tank? Sometimes, he says, just the availability of additives makes you think there’s a problem when there really isn’t one. Depending on the location of your car’s fuel pickup, water in the tank, while not ideal, might not even cause an operational problem. 

Second, consider the cost. A 12-ounce bottle of water remover usually retails for about $2.29. That seems reasonable until you look at the price of the raw secret ingredient: The current industry-average price for a gallon of methanol, he says, is about $1.19. 

Some water remover additives use isopropyl alcohol in a higher concentration than the rubbing alcohol found at the pharmacy, he adds. Isopropyl alcohol also acts as a co-solvent, Santner explains, but it has a lower polarity than methanol.

Join Free Join our community to easily find more Sunoco, Sponsored Content, Fuel Facts and Water articles.
More like this

You'll need to log in to post.

Our Preferred Partners