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Is drygas still necessary?

Since I live in a climate where the temperature is likely to go below zero every winter,I’ve always given a dose of drygas to the tanks of our cars every fall. In the past I’ve had a few bad experiences with fuel lines freezing.

Now that we’re getting ethanol in our unleaded, is this still necessary?

If ethanol is in your fuel not needed at all. In NH where I live I believe up to 10% ethanol which is a stronger concentration than most bottles of the stuff.

According To EPIC (The Ethanol Promotion & Information Council), No.

I live where the temperature typically varies up to 130F from summer to winter (+95F to -35F. I don’t use gas line antifreeze or gasline drier (DRYGAS is the Cristy brand name) and never have problems. I suppose you could put some in if you’d like, ethanol or no ethanol. I do tend to live off the top half of my tank in the winter to keep air out (prevents condensation) of the tank and for the ballast, though.

EPIC covers your question in their FAQs.
Here’s EPIC’s link:

I’m skipping my annual drygas purchase this year because almost all of the gasoline in my area has up to 10% ethanol already in it.

In 45 years of driving, I have only had problems twice and I have never used the stuff as a preventative. I do live in a cold winter area.

One time I ended up with a nearly full tank of water with about a quarter inch of gas floating on top. The other time I had about a quart of water that had been added to my diesel fuel (don’t buy fuel from back woods stations). I really don’t think the stuff is necessary.

In neither case would having used the stuff have helped.

Ethanol alcohol doesn’t mix well with gasoline. So over time it can phase seperate from the gasoline and settle to the bottom of the tank. When this happens, it also phase seperates any moisture it absorbed from the gasoline to the bottom of the tank. This moisture then phase seperates out of the ethanol and you end up with water sitting at the bottom of the gas tank. This is one of the drawbacks of using ethanol in gasoline.

Isoprophyl alcohol on the otherhand doesn’t phase seperate out of the gasoline. So it stays mixed with gasoline along with any moisture it aborbed so it can be carried off and burned in the engine. That’s why all fuel system anti-icing products are made up from isoprophyl alcohol.


Tester, Are You Recommending The Use Of Fuel System Anti-Icing Products Containing Isopropyl Alcohol?

Isn’t that what I just read was in short supply for deicing airliners? (That’s what we used to spray on small planes at the small airport where I worked, as a teen.)

Will it help to eventually get out any water sitting in the bottom of a fuel tank?

Would the answer to linclinc’s question, “Now that we’re getting ethanol in our unleaded, is this still necessary?”, be “Yes” ?

I value your input. Thanks.

Here’s a good article on the subject-

Thanks TwinTurbo. That’s Interesting.

So, keeping the tank filled is a good idea, especially in winter.

Would the answer to linclinc’s question about Dry Gas™, “Now that we’re getting ethanol in our unleaded, is this still necessary?”, be “Yes” ?

I value your input. Thanks.

Great! Now I guess I’ll have to start buying DryGas again once or twice a year.

I had a gas line icing problem once, back in the early 70s before there were any oxygenating additives. Almost a linear foot of ice came streaming out of my fuel line when disconnected from the carb. I spent 40 years living through bitter Midwest winters and I can count on one hand (even a punch press operator’s hand;) the number of times I was scared into using dry-gas. Ethanol has been added to gas in that region for quite some time now.

Years ago, all gas stations had outside displays with dry gas right next to the pumps. I haven’t seen that practice for more than a decade so I believe consumption of the product is way down. I expect people have come to realize that the risk of water in the gas tank is minimal.

That article highlights the circumstances required to have phase separation occur. While we occasionally hear of someone getting a tankful of bad gas, I believe it is extremely rare. In those cases, a single bottle of dry gas probably wouldn’t have helped anyway. I still live in a cold climate and believe the risk is so small, I won’t be buying any dry gas for the foreseeable future. YMMV.