I don't drive my FD much, probably 2k this year. (When I do drive it, I drive it hard). But in any case, the idea of 10% ethanol fuel sitting in my fuel system and tank for months at a time is making me uncomfortable. And winter is almost here.

I've seen the cases of ethanol absorbing water when the fuel is not used for a long time and rusting the insides of the tank and fuel lines. I can get ethanol-free gas at a station about 10 miles away but it's not something I can do for every fill-up.

Any experts on this subject? Will plain old Sta-Bil do a good enough job?

Dave

 

this is something that im wondering as well...

i am expected to deploy for 6 months to Qatar in the next few months and my mint FD will be in storage for that time.

there are no fuel stations that dont have 10% ethanol mixed in and this seems to disturb me a bit.

 

I would not consider it a real threat. My truck is diesel, and I talk to a lot of guys with diesel trucks. It's not uncommon for the diesel to sit in the trucks for extended periods,w ithout fuel stabilizer. Now, this may seem like a different beast, but there is water in diesel. In fact, there's so much water in diesel, that there's actually a device in line between the tank and the engine that is a "water remover". When driving, if a "water in fuel" light comes on on my dash, I know the device is full and must be emptied. It's not a difficult task, though. Still there's regularly water in my fuel system and it's never caused a problem.

One thing that is very important though. When storing any vehicle for an extended period of time, fill the tank to the brim. Water will not cause an issue if there is fuel there. If the tank is not full, the water in the fuel WILL cause tank rust. That means rust particals going into your engine, and that's not good. I'd rather deal with a tank of stale fuel than I would a rusty gas tank. That's one of the leading problems with older motorcycles, the tanks get rusty inside. Rust cannot occur if there is fuel against the metal.

So fill up, put some fuel stabilizer in, drive a little to get the stabilized fuel into the system, then park it for no more than 2 years. If longer than 2 years, you'll have to replace the fuel. But you won't have a rusty fuel tank.

 

These guys have an adgenda but the facts on this page are accurate.
http://www.fuel-testers.com/marine_b..._problems.html
I don't know of any additive that will prevent water absorption over time if stored in an unsealed container. In my opinion if your car is stored in a stable temperature area and the fuel tank is not “breathing” due to daily temperature swings the fuel will probably be OK for several months. Water in the ethanol should not be a corrosion concern as long as phase separation has not occured.

 

how about a little PREMIX, 1oz. to one gallon, 2stroke oil.

been doin it for 8yrs, no rust, i check the in-line filter about once a yr.

 

Just got this emailed to me from The Eastwood co. I thought that it was a gimick but now reading this thread it might be worth buying...

http://eastwood.ip07.com/form/eastwo...hcgjb5d43gd3r0

 

I would use 100 unleaded that has no ethanol in it.
Fill it up, and you'll be fine.

 

I can do the no ethanol for a winter fill-up, but not 100 octane.

The more I think about it, the risk is really in summer when the car tends to be parked outside and not run for days or even weeks at a time.

David

 

The Eastwood product seems to be just what your looking for. I think STP also makes a similar product. http://www.stp.com/products/fuel-add...water-remover/

 

Ya that would be great if the sold anything over 91 here... lol

 

stabil is always good.

we've had 10% ethanol up here forever and i'll be honest, i've yet to hear of some kind of catastrophic failure because of it.

Aside, if you get Shell V-Power in the US, it has 0% ethanol....at least up here it does.

 

Ethanol doesn't absorb water, it's actually soluble in water, which means something different.

Ethanol would be beneficial in lowering the freezing temperature of the gas in the tank. I'm not convinced that ethanol is solely the culprit for rust however. There is air (which includes water vapor) in the gas tank, and when the temperature drops, the water vapor condenses into liquid water, which would be the cause of the rust. If the car is sitting motionless for a while, and/or the temperature drops dramatically, the fuel in the system will occupy less volume as it's temperature decreases, causing a vacuum potential for air pockets to introduce themselves into the fuel lines from the air vapor present in the tank above the fuel.

It still would require a combination of extreme conditions and some length of time for this occur. It's also important to consider the age of our cars. Not everything is sealed airtight like when they rolled off the line in Hiroshima 17 years ago.

There are three ways to help prevent oxidation:

1) Remove any reducing agents from the internals you're trying to protect. Reducing agents would include oxygen, sulfur, and carbon dioxide to name a few potential metal-lovers. And there's no realistic way to purge the tank of all it's oxygen, CO2 and H2O vapor.

2) Bolt a section of copper in direct contact with the metal fuel line(s). The copper will serve as a "sacrificial" metal that has a higher oxidation potential than the lines. This means that electrons will will be more drawn to the copper than the fuel lines. The problem with this is that over time, the oxidized copper will be dissolved into the fuel, so you'd be running off of unleaded coppered gas. Ships use "sacrificial metals" to prevent their iron hulls from rusting.

3) Try the "fuel stabilizers." Although there may be some accuracy to their claims, it would be hard to scientifically measure their effectiveness. I say this partly because the manufacturers can't make it so potent that is reduces your gasoline to a non-volatile liquid incapable of adequate combustion. They may contain drying agents which attract or form hydrogen bonds with water (or water vapor), or they may contain structures containing hydrophilic active sites - or pockets - that surround the H2O and prevent the oxygen from interacting with the metals. (For an experiment, this may be observed by taking the dessicant packets that came in the pockets of your new jacket and placing them in a glass of rubbing alcohol; you will observe water "bubbles" forming around the dessicant as it pulls the water out of the alcohol/water mixture.)

It's difficult to store a car with absolutely no oxidation occurring.

Even if you run the car out of gas (until it stalls), you'll just end up with oxygen and CO2 in the lines, and they're definitely in whatever chambers exist in the engine. When I would leave a car parked for a while, I made it a point to start it and allow it to idle for a few minutes at least once a week, and that practice has worked fine.

As a final thought... Don't believe everything you read on the forums, special-interest websites, or what your Facebook friend's buddy said he heard about something another guy saw on youtube 5 years ago, but he was drinking and he's not sure. And furthermore, spreading hearsay and posting uneducated guesses about what should or should not go into the gas tank is pretty lame.

I don't label myself an expert, but I've spent hundred of hours in Chemistry and Organic Chemistry Labs while in my Pre-Medical classes working with chemicals ad nauseam, so I am able to at least offer an educated explanation, albeit a really long one.

 

There are 76 stations that sell 100 out of the pump. You'll have to look them up online. 5 years ago it was 6 dollars a gallon. I'll be its about 8 bucks right now.

 

What's going on is that with higher ethanol content in fuel the shops are seeing more repairs related to rusting fuel lines. This is an issue for lightly driven vehicles. The increase in fuel line damage is reported by shops who perform the work, not one individual.

David

 

chem major lol? I learned such things when I took physical chem few year ago.

For sacrificial anode you think itll do its job attached outside the tank? Im guessing no

Another thing, if there is already water in the tank, ethanol shouldn't react with h20 given its environment. U would prob need to add heat...

 

Looks like we should take your advice.
Hyundai says it is hygroscopic:

http://www.hyundai.com.au/FAQ/default.aspx

and honda: http://marine.honda.com/owners/fuelrecommendations
and http://harvardmagazine.com/2006/11/t...-illusion.html
and http://en.wikipedia.org/wiki/Hygroscopy

 

Shell V-Power has always been advertised as 0% ethanol so fill it up with that? Unless its different in the states.

thewird

 

Why is the tank not aluminum? Safety issue? Aluminum forms a thin non-porous oxide on its surface with time; no rust, and no particles breaking loose. And if the aluminum is anodized, it won't even do that.

 

When aluminum corrodes it tends to create pinhole leaks. It would corrode from the outside not inside.

Another problem is aluminum strain hardens quickly, so it's hard to work with.

 

I thought the tanks were coated on the inside.

 

I doubt there's any real advantage in terms of weight, or that MAZDA built these things with enthusiasts concerns in mind for extended storage. I'd say cost, materials and in manufacturing, is the most likely reason.

 

THey're galvanized I think, but they still spot welded in the baffles and stuff without recoating. So there are places where the coating is broken through.

My diesel truck has a poly tank. So other materials are possible.

Back to the subject though, there are plenty of metal hard lines that will corrode from inside. If there were any corrosion I'd pull them all and get them replated inside and out. Given the new consideration of ethanol I'm definitely going to keep a sharp eye out for corrosion anytime I'm in my fuel system, and fill up my FD at the ethanol-free station whenever possible.