Gas stabilizer
Thread Starter
Le Mans Master
Joined: Jan 2001
Posts: 9,248
Likes: 221
From: Dryden MI
Gas stabilizer
A friend and I had a discussion on adding stabilizer to the gas before putting the car away for the winter months. I used to do it to all my vehicles and lawn equipment, cheap insurance as gas years ago would become varnish and cause major problems. I no longer add stabilizer to any of my gasoline engines. One of my cars sat for two years without a fuel additive and it started with no problems. Is stabilizer necessary with the modern blends of gas that is produced today? I know it is much cleaner than gas produced in the 70s and early 80s. Opinions, thoughts or have I just been lucky? Storage is usually 6 months.
Drifting
Joined: Jan 2005
Posts: 1,942
Likes: 1,328
From: Houston Tx
You hit the nail on the head. Luck determines whether you have a problem. Most gas is dry enough that you get by ok, but all gas contains a little dissolved water. As the gas cools over the winter, it will dissolve less and less water. So if you are unlucky, and your last fill-up was from a batch of gas having more dissolved water than usual, then as your gas cools over the winter, you will end up with a small water layer in the bottom of your tank. This can happen both with gas that does and doesn’t contain ethanol, the only difference being that if it happens with ethanol-containing gas, the water layer will be somewhat bigger. Most stabilizers prevent water from dropping out as the temperature falls, even if the gas started out carrying max dissolved water. Use of the words “most stabilizers” carries an important warning. If your area’s gas has ethanol (and most areas do), then IPA-based stabilizers like SeaFoam will not keep the dissolved water in solution. So if you are in an area with ethanol in gas, be careful to use a stabilizer that does not list IPA (isopropyl alcohol) as an ingredient.
Team Owner
Joined: Sep 2005
Posts: 20,352
Likes: 568
From: Ventura County, Calif
This has been a topic of discussion (disagreement) for many years. There are valid opinions on both sides, some say use it and some say don't have to.
I think the consensus of opinion is that modern gas is okay for a year, not like the gas in the old days. BUT as mentioned above, there is the new issue of ethanol blends.
My opinion, you live in a COLD part of the country, I think it would be cheap peace of mind to use an "appropriate" stabilizer, ie: if ethanol is in use in your area or not. FWIW, I used to store the car for 6 months in Portland and I used StaBil every year. I felt better and never had a problem. StaBil now has a product for ethanol blend gas and their new StaBil 360 for year round.
I think the consensus of opinion is that modern gas is okay for a year, not like the gas in the old days. BUT as mentioned above, there is the new issue of ethanol blends.
My opinion, you live in a COLD part of the country, I think it would be cheap peace of mind to use an "appropriate" stabilizer, ie: if ethanol is in use in your area or not. FWIW, I used to store the car for 6 months in Portland and I used StaBil every year. I felt better and never had a problem. StaBil now has a product for ethanol blend gas and their new StaBil 360 for year round.
Le Mans Master
Joined: Jun 2013
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Likes: 942
From: Colorado
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Fuel stabilizer is cheap. Why risk it. Reminds me of a guy who paid $30k for a motorcycle, and then strapped it down to a trailer with $5.00 straps. First corner he took, and one broke. Bike was totaled. 
Last edited by Rky Mtn C6; Oct 23, 2016 at 10:44 PM.
Senior Member since 1492
Joined: Aug 2000
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From: Just because I'm paranoid doesn't mean people aren't out to get me...
St. Jude Donor '09
I used it for years in my lawns mowers, chain saw etc and my 70 vette. However a few years ago my 70 vette was left sitting for over 2 years without any stabilizer. The gas in the tank was a little yellow but it started right up.
in 2014 I stored a 2012 SHO for 6 months without it and had no problems. I plan to continue using it in my chain saws, lawn mowers & snow throwers though.
in 2014 I stored a 2012 SHO for 6 months without it and had no problems. I plan to continue using it in my chain saws, lawn mowers & snow throwers though.
Thread Starter
Le Mans Master
Joined: Jan 2001
Posts: 9,248
Likes: 221
From: Dryden MI
You hit the nail on the head. Luck determines whether you have a problem. Most gas is dry enough that you get by ok, but all gas contains a little dissolved water. As the gas cools over the winter, it will dissolve less and less water. So if you are unlucky, and your last fill-up was from a batch of gas having more dissolved water than usual, then as your gas cools over the winter, you will end up with a small water layer in the bottom of your tank. This can happen both with gas that does and doesn’t contain ethanol, the only difference being that if it happens with ethanol-containing gas, the water layer will be somewhat bigger. Most stabilizers prevent water from dropping out as the temperature falls, even if the gas started out carrying max dissolved water. Use of the words “most stabilizers” carries an important warning. If your area’s gas has ethanol (and most areas do), then IPA-based stabilizers like SeaFoam will not keep the dissolved water in solution. So if you are in an area with ethanol in gas, be careful to use a stabilizer that does not list IPA (isopropyl alcohol) as an ingredient.
Race Director
Joined: Jul 2005
Posts: 12,045
Likes: 3,588
From: Central MO
I use it in anything that has a gas engine when it will be stored over the winter - boats, personal watercraft, lawn mowers, chainsaws, weed eaters, leaf blowers, farm tractor, generator, etc. It's cheap insurance.
Drifting
Joined: Jan 2005
Posts: 1,942
Likes: 1,328
From: Houston Tx
Thanks, I never considered the water part. I always thought it was break down of the gas over time. Gas without ethanol is not easy to locate. Due to work relocation I was unable to prepare the 78 for storage and it sat for two years and started up with no issues. Unaware too that some stabilizers will not work with ethanol. Good information.
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