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I was always told you should keep your tank full to reduce condensation in the tank which puts water in the fuel. I was also told gas goes bad after 2 to 3 months and gums up. If I fill up every time I go out I am not using all the gas in the tank and some of it ends up being more then two months old. What's worse old gas or condensation in the tank?
I was always told you should keep your tank full to reduce condensation in the tank which puts water in the fuel. I was also told gas goes bad after 2 to 3 months and gums up. If I fill up every time I go out I am not using all the gas in the tank and some of it ends up being more then two months old. What's worse old gas or condensation in the tank?
I was always told you should keep your tank full to reduce condensation in the tank which puts water in the fuel. I was also told gas goes bad after 2 to 3 months and gums up. If I fill up every time I go out I am not using all the gas in the tank and some of it ends up being more then two months old. What's worse old gas or condensation in the tank?
I have searched for this very question multiple times...I've heard that you should keep it filled up & use some sort of stabilizer to combat the fuel going bad/moisture. That way, the fuel pump is cooled down by there always being fuel in the tanks. I've also heard that you should run it to empty so there is always new fuel being filled into the tanks. I put a fuel catalyst in at every fill up & once in awhile I'll pour in a bottle of Stabil 360 too. Sometimes I run it down under 1/4 tank & sometimes I fill it up when it's up above 1/2. I use Nitrogen Enriched Shell 93 almost always.
This comment probably doesn't help the thread much...Mine is a 2013 Grand Sport so I don't imagine that I'll have any fuel related issues.
Last edited by dmoneychris; 11-15-2015 at 06:59 PM.
I have searched for this very question multiple times...I've heard that you should keep it filled up & use some sort of stabilizer to combat the fuel going bad/moisture. That way, the fuel pump is cooled down by there always being fuel in the tanks. I've also heard that you should run it to empty so there is always new fuel being filled into the tanks. I put a fuel catalyst in at every fill up & once in awhile I'll pour in a bottle of Stabil 360 too. Sometimes I run it down under 1/4 tank & sometimes I fill it up when it's up above 1/2. I use Nitrogen Enriched Shell 93 almost always.
This comment probably doesn't help the thread much...Mine is a 2013 Grand Sport so I don't imagine that I'll have any fuel related issues.
Thanks for all the answers. I also have a 13 Grand Sport.
I've fired up cars that have sat for as much as 15 years. How well they ran is not the issue, since just getting them running was the task at hand.
Since E10 is pretty much that standard gas found everywhere in the country, the 10% alcohol is more than enough to compensate for any condensation you think you might have. For a long time now, car's fuel tanks have been sealed from the atmosphere. The only opportunity to get condensation is during the filling when you take the cap off. Don't fill your tank while standing in rain and you'll never have a problem.
I usually fill up when I'm between empty and 1/4 tank. 128K miles and never a fuel problem when using top tier gas.
It wasn't clear whether you are storing the car or wondering about normal usage. For the later, I would council that you not overthink it. Gas goes in the tank and foot goes to the floor.
Regarding long term storage, I've think your best option is a full tank + stabil.
I'm with other posters here. For most of the country where only fuel+10%EtOH is available at the pump, a full tank (to minimize condensation/water accumulation) plus a dose of some type of fuel stabilizer is the ticket. If it's only 2-3 months of storage, I probably wouldn't worry too much about stabilizer. I have the "luxury" of living near a station that offers 91 octane pure gas (no EtOH)--at an outrageous premium price, of course--and that's what I use to fill up the last time before storage. That way, I have no worries about ethanol picking up water. You can frequently find pure gas at a marina or boat yard, if you live near water.
I'm with other posters here. For most of the country where only fuel+10%EtOH is available at the pump, a full tank (to minimize condensation/water accumulation) plus a dose of some type of fuel stabilizer is the ticket. If it's only 2-3 months of storage, I probably wouldn't worry too much about stabilizer. I have the "luxury" of living near a station that offers 91 octane pure gas (no EtOH)--at an outrageous premium price, of course--and that's what I use to fill up the last time before storage. That way, I have no worries about ethanol picking up water. You can frequently find pure gas at a marina or boat yard, if you live near water.
Good call on the Pure Gas. I filled up a few times with it when I was visiting my parents in Vermont. The car ran noticeably better using it. It's probably a good idea to use it for storage. http://pure-gas.org/
Luckily, Our premium gas still does not contain 10% ethanol, so that is what I use in the C6. I also use it for the last fill up in the ride on lawnmower and snow blower, with stabil.
For my DD, I use regular which contains 10% ethanol, but it is never sitting for too long, so no worries.
Never have any issues with rubber deterioration or such.
I'm with other posters here. For most of the country where only fuel+10%EtOH is available at the pump, a full tank (to minimize condensation/water accumulation) plus a dose of some type of fuel stabilizer is the ticket. If it's only 2-3 months of storage, I probably wouldn't worry too much about stabilizer. I have the "luxury" of living near a station that offers 91 octane pure gas (no EtOH)--at an outrageous premium price, of course--and that's what I use to fill up the last time before storage. That way, I have no worries about ethanol picking up water. You can frequently find pure gas at a marina or boat yard, if you live near water.
You have that a little bit backwards about the ethanol. Ethanol will mix with both fuel and water, so that any water/condensation will not be separate in the tank. Since fuel pickups are at the bottom of the tank and water is denser than fuel, any water at the pickup point has the opportunity to freeze and shut off the fuel supply.
In the years before E10 existed, it was common to add alcohol to the fuel in the winter to mix with the fuel and condensation and therefore prevent freezing
In high humidly climate like where I live and you have a car with a metal tank you can get condensation, but with the type of tanks in the vette it should not happen.HOXXOH is correct in his post and he lives in a very dry area..
Last edited by Cherokee Nation; 11-17-2015 at 12:11 PM.
Reason: add
You have that a little bit backwards about the ethanol. Ethanol will mix with both fuel and water, so that any water/condensation will not be separate in the tank. Since fuel pickups are at the bottom of the tank and water is denser than fuel, any water at the pickup point has the opportunity to freeze and shut off the fuel supply.
In the years before E10 existed, it was common to add alcohol to the fuel in the winter to mix with the fuel and condensation and therefore prevent freezing
Well, we can agree on some things....and maybe not on others.
It's true that ethanol will help mix water into pure gas, preventing fuel line freeze-up. However, it is UNTRUE that water will mix with pure gas to any appreciable extent. That is EXACTLY WHY freeze-up used to happen with the old non-E gas--the water would remain undissolved in the fuel tank and would fall to the bottom (higher density than gas) and subsequently, when the temps dropped below 32*F, the water would freeze in the fuel line and prevent fuel flow. The effect I was referring to--and THE MAIN ISSUE with the E-gas--is that water has a greater affinity for ethanol than for gas and at a certain concentration will form an azeotropic mixture with the ethanol which will then separate from the gas (phase separation: http://www.lcbamarketing.com/phase_s...hanol_blen.htm). In normal everyday driving, this doesn't cause any real issue because the water/ethanol mix will support combustion and small amounts will run thru the engine just fine. However, when you let that separated water/ethanol mix sit for a long time, it will support bacterial growth and form a nasty gel, which can clog small orifices and corrode steel that comes in contact with it.
Originally Posted by Cherokee Nation
In high humidly climate like where I live and you have a car with a metal tank you can get condensation, but with the type of tanks in the vette it should not happen.HOXXOH is correct in his post and he lives in a very dry area..
Condensation happens in the headspace of any type tank--metal or plastic. The headspace is directly vented to the atmosphere and can pick up moisture from the air in a high humidity environment. You're correct that it won't cause corrosion in our plastic tanks. It can cause corrosion in any metal parts it contacts, like fuel lines, pumps, injectors, etc.
As long as you're regularly driving your car and refreshing your fuel every few months or sooner, you shouldn't have any issues. Long term storage, especially in areas of the country that have wide swings in temps and humidity during winter months, is another ball of wax...
Well, we can agree on some things....and maybe not on others.
It's true that ethanol will help mix water into pure gas, preventing fuel line freeze-up. However, it is UNTRUE that water will mix with pure gas to any appreciable extent. That is EXACTLY WHY freeze-up used to happen with the old non-E gas--the water would remain undissolved in the fuel tank and would fall to the bottom (higher density than gas) and subsequently, when the temps dropped below 32*F, the water would freeze in the fuel line and prevent fuel flow. The effect I was referring to--and THE MAIN ISSUE with the E-gas--is that water has a greater affinity for ethanol than for gas and at a certain concentration will form an azeotropic mixture with the ethanol which will then separate from the gas (phase separation: http://www.lcbamarketing.com/phase_s...hanol_blen.htm). In normal everyday driving, this doesn't cause any real issue because the water/ethanol mix will support combustion and small amounts will run thru the engine just fine. However, when you let that separated water/ethanol mix sit for a long time, it will support bacterial growth and form a nasty gel, which can clog small orifices and corrode steel that comes in contact with it.
Condensation happens in the headspace of any type tank--metal or plastic. The headspace is directly vented to the atmosphere and can pick up moisture from the air in a high humidity environment. You're correct that it won't cause corrosion in our plastic tanks. It can cause corrosion in any metal parts it contacts, like fuel lines, pumps, injectors, etc.
As long as you're regularly driving your car and refreshing your fuel every few months or sooner, you shouldn't have any issues. Long term storage, especially in areas of the country that have wide swings in temps and humidity during winter months, is another ball of wax...
Just my $0.02, but I agree with icntdrv55... Gas with ethanol does seem to go "bad" far faster than the old non-alcohol added formulation. While people don't see gas problems all that often with cars - talk to a small engine mechanic, and ask them about the problems they are seeing every day with old gas (particularly with 2 stroke motors that use diaphragm carbs). I've opened up more than one carb on small engines where the fuel that was left in the float bowl decayed into a green, slimy, sticky, gooey mess.
. I strongly recommend filling the tank AND adding a fuel stabilizer before putting the car away for the winter. Yes - this costs a few $$$, but think about how much "fun" it would be to drain the gas out of your car, then how "easy" it is to get rid of the old gummy gasoline... Yes, you can try to get the gas out by pumping it through the fuel system - but if the gas is indeed bad - plan on changing the fuel filter after you do that... Fuel stabilizer isn't all that expensive, and if it saves a problem even once - wouldn't you say it was well worth it ???
I've had 14 month old 93 in my turbo rotary and the car started up and idled just fine. Didn't drive hard on the car obviously.
I think top tier gases now it takes more than 2-3 months before it goes "bad". More like 6+. And even then you can probably still drive the car easy until it all burns off.
Or you can just put a fuel stabilizer and have a peace of mind.
Well, we can agree on some things....and maybe not on others.
It's true that ethanol will help mix water into pure gas, preventing fuel line freeze-up. However, it is UNTRUE that water will mix with pure gas to any appreciable extent. That is EXACTLY WHY freeze-up used to happen with the old non-E gas--the water would remain undissolved in the fuel tank and would fall to the bottom (higher density than gas) and subsequently, when the temps dropped below 32*F, the water would freeze in the fuel line and prevent fuel flow. The effect I was referring to--and THE MAIN ISSUE with the E-gas--is that water has a greater affinity for ethanol than for gas and at a certain concentration will form an azeotropic mixture with the ethanol which will then separate from the gas (phase separation: http://www.lcbamarketing.com/phase_s...hanol_blen.htm). In normal everyday driving, this doesn't cause any real issue because the water/ethanol mix will support combustion and small amounts will run thru the engine just fine. However, when you let that separated water/ethanol mix sit for a long time, it will support bacterial growth and form a nasty gel, which can clog small orifices and corrode steel that comes in contact with it.
Condensation happens in the headspace of any type tank--metal or plastic. The headspace is directly vented to the atmosphere and can pick up moisture from the air in a high humidity environment. You're correct that it won't cause corrosion in our plastic tanks. It can cause corrosion in any metal parts it contacts, like fuel lines, pumps, injectors, etc.
As long as you're regularly driving your car and refreshing your fuel every few months or sooner, you shouldn't have any issues. Long term storage, especially in areas of the country that have wide swings in temps and humidity during winter months, is another ball of wax...
You're dead on..e10 doesn't store long at all. Real gas can go a long time before it turns to varnish, but e10 will go bad in a year or less for sure.
If you don't believe me watch Jay Leno's Garage or Road Kill.
I maintain fuel for generators (hurricanes) for 6 months to sometimes one year and I always use Sta-Bil. It's a great product and has never failed me even with e10. I would not store a car without it. I put in the proper Sta-Bil mix for a full tank and fill the tank and it works great.
Not to steal the thread, but for those (like myself) that do use fuel stabilizer - is Sta Bil the overwhelming favorite - or are you using other stuff.
I used to be firmly in the Sta Bil camp - but recently I've tried Star Tron and it seems to work (based on the wholly unscientific technique of looking at the color of the gas when you pour it into the tank after it's been around for a while) as well as - if not better than Sta Bil. The problem is that you only find out how effective stabilizer is when the stuff DOESN'T work. I also don't know if Sta Bil or Star Tron impact the octane rating of the stored fuel.
One other thing I'll mention - I've been told by more than one small engine guy that they seem to see fewer problems with 93 octane fuel going bad than with regular (87 octane) fuel going bad. Don't know if it's just that people who are willing to spend the extra $$$ for premium for small engines are typically a bit more diligent about their equipment, or if the additive package put into the higher octane fuel tends to better ward off fuel degradation.
11-15-2015, 05:51 PM
Gas to fill or not to fill
