Ethanol fuel mix degradation

[Larks]

Just reading in Elf's thread about her mower and chipper problems and Phil's comment about ethanol in fuel degrading rubber components. I hadn't heard of this before and didn't realise that it was a problem.

I have a five kva petrol generator, about 4 years old, I used it continuously for about six months when I was building my house but now I start it every six months or so to check it as a back up for when our mains power goes down.

When I went to check it on the weekend, not only had the rubber fuel lines hardened and started to perish, but the aluminium fuel cock had broken from the fuel tank at its thread. When I tried to take it off of the fuel line to get a replacement the bayonet for the fuel line broke off as well.

Basically the aluminium fuel cock would just about crumble if I were to grind it hard enough with my fingers - and that is not because of my super human strength.

Is this perhaps a result of the ethanol in the fuel as well? Or is it just maybe a cheap, crappily manufactured fuel cock? Has anyone had such an experience with aluminium fuel components perishing?

[CByrneiv]

I would guess the "aluminium" isn't. It's probably potmetal; and has electrolytically corroded to the consistency of sodacracker.

That said, ethanol would definitely make that process worse.

[Larks]

I would guess the "aluminium" isn't. It's probably potmetal; and has electorlytically corroded to the consistency of sodacracker.

That said, ethanol would definitely make that process worse.

This one has (so far) been a land based genny (and being petrol – gasoline – will probably remain that way) so am not so sure about the electrolysis. Leaving the fuel mix my only real suspect.....

[CByrneiv]

Old gas tends to accumulate a lot of water in it, never mind the other conductive elements, and the solvents.

Believe me, galvanic reactions definitely occur in gasoline fuel systems. Besides which, the nasty bits in gas can eat some of the metals often in pot metal (like zinc and tin).

In general, if I'm overhauling a genset, or anything else with a small motor likely to sit around inactive for any length of time; I'll take any aluminum, zinc, potmetal, or otherwise suspect fittings out of the system, and replace them with brass, bronze, or stainless. Unfortunately, as so many of them are made in China now, "suspect metal" tends to be all over the place.

[Larks]

Thanks for the response, something that I really wasn't aware of - I've ordered a new tap and hoses but didn't think to ask for a brass or bronze one. I'd better change the order before they get it in and charge me for it.

[Breakaway]

Ethanol attracts and holds water (hydroscopic). So it can lead to increased corrosion risk. In boats here in the US, though, its those with fiberglass fuel tanks that have been most deleteriously affected. Apparently, the alcohol is a good solvent for certain resins and fuel systems and engines were getting clogged with the released bits from dissolving tanks. Degraded fuel lines, some seal damage, and for two stroke engines, a lack of lubricity during combustion have been other problems.

Solutions: None are 100-percent. But using fuel stabilizer all the time, not just for storage, and installing the finest water-separating fuel filter the engine will stand (filter elements as fine as 10-microns), seem to have positive results.

Its more of a problem in boats--or in a genset like yours--because, unlike autos, the fuel isn't turned over/used up and replaced as often.

[skipper68]

just great!the idiots in ny made ethanol in fuel for marine use the law as of yesterday.bad enuf the dum dums were sneeking in reg &having fuel leaks from fiberglass tanks,now the whole states going to be having to clean up spills,and boats blowing up.thought some legislater(smartly)was excluding marine fuel just for those reasons.i'm soo mad!!!.

[Breakaway]

'm soo mad!!!.
Me too.

[AstoriaDave]

Three seasons (all but the frozen times) of use in my Bartender of the Oregon 10% alcohol fuel and absolutely no issues or problems. I have not tried to keep my tanks full in storage or empty in storage, and have had two-to-four-month intervals when the boat just sat there.

I think most of the issues people claim with alcohol in fuel are nonstarters ... and more likely stem from poor hygiene or other sources of water entry..

What's my secret? I use the BLUE Stabil at a dose of one ounce for every five gallons at each fill. Never miss one. Stabil prevents any problems here in the very moist, very wet, high humidity climate of the coast of Oregon, average rainfall about six feet where I live. Rained an inch and a half last 24 hours.

Mind, I hate ethanol in fuel for a better reason: loss of power. Ethanol is an oxygenated fuel, and does not have the caloric content of al all-hydrocarbon fuel. If I could get some all-hydrocarbon fuel, I bet it would increase my mileage (or) increase my engine's power. But, that's politics, not technology.

[Breakaway]

Ethanol problems arent that prevalent in newer boats with newer power--provided like you, the owners use a good stabilizer. Its older equipment that contains seals, fiberglass tanks and other fuel system components that the alcohol, a good solvent as we all here no, breaks down.

And your point about power is well taken.

[skipper68]

thanks for the info on the blue. now,2-galvinized(thank goodness) 88gallon tanks x$4.25 per gallon,...well heck,the xtra cost for the blue, on top of the fuel ,when you then add all of our tax dollors to subsidize the corn industry,which cost around 100$per gallon they estimate to produce that gallon of ethonal, is is a darn good deal!!aaarrrggg:rolleyes:and then,the lead additive we add to the old motors.im starting to smell alot of dock rats..

[Venchka]

I had a long talk about this with my local small engine repair guy. I was interested in preserving my new Stihl chainsaw & weedeater and my 1980 Suzuki (Arctic-Spirit) outboard.
He said:
1. Mix the gas/oil 1:40 or a bit more. Example: 1 gallon size Stihl oil bottle to 0.8 gallons of 89 or better octane gas.
2. Don't leave gas/oil mix in the tank.
3. Don't use gas/oil mix older than 30 days.
BTW, I filled the outboard Sunday for the first time in 2 years with fresh gas/oil at 93 octane & 1:39 mix. 5-6 pulls to fill the carb. After that, started on the first pull. Ran two tanks dry without skipping a beat. I will never ever voluntarily replace this motor.
YMMV

[skipper68]

another thought:if its so great lets see them mandate it for airplanes too!!that'll get the powers that be start rethinking!! :D :(

[jonboy]

Ethanol has been the only fuel pretty much, in Brazil for years and years.. there's nothing inherently wrong with it... Lack of power? I used to race speedway and grasstrack bikes that ran on ethanol or methanol because it gave more power.
I have experienced crumbly petcocks and hardened fuel lines, particularly the clear plastic with criss cross nylon braiding standard on Brit bikes since I was a snapper, with all kinds of petrol vehicles.and garden kit..fuel filters and air filter cleanliness I would bet is more an issue than ethanol/ mix/ purity/ additives problems.

[Bob Adams]

I had a long talk about this with my local small engine repair guy. I was interested in preserving my new Stihl chainsaw & weedeater and my 1980 Suzuki (Arctic-Spirit) outboard.
He said:
1. Mix the gas/oil 1:40 or a bit more. Example: 1 gallon size Stihl oil bottle to 0.8 gallons of 89 or better octane gas.
2. Don't leave gas/oil mix in the tank.
3. Don't use gas/oil mix older than 30 days.
BTW, I filled the outboard Sunday for the first time in 2 years with fresh gas/oil at 93 octane & 1:39 mix. 5-6 pulls to fill the carb. After that, started on the first pull. Ran two tanks dry without skipping a beat. I will never ever voluntarily replace this motor.
YMMV

I'd add always use a stabilizer. (BTW, the Stihl 2 stroke oil contains stabilizer)

[elephant_man]

Could the detergent in the fuel be a problem? I still believe its in there just to keep the roadways from getting to much of a sheen. If you don't believe me take a cup of water and put a drop of fuel in it and watch it disperse.

[Stan D]

Ethanol in the combustion chamber creates carbon(harder than the hardest steel)and will kill the cylinder walls and rings. A product called Sea Foam reduces the affect of ethanol in producing carbon, and will help clean out carbon already there.

[bluedog225]

? carbon....like diamonds? or like coal? Not produced w/o ethanol?

[Dan McCosh]

Ethanol has been a common additive to gasoline since rhe 1970s. for two reasons. It is an octane-enhanser, replacing in some cases lead in gasoline. Other types of alcohols can serve the same purpose. It also is considered a kind of gasoline-stretcher, displacing some of the petroleum-based fuel in gasoline.

Most engines have already been designed to accept significant quantities of ethanol as a result. Ethanol adsorbs water, which means that it will make a gas tank full of a kind of water/gasoline solution after it stands for a while. Ethanol also is a significant solvent for some rubber and plastic compounds, which means that is wreaks havoc on some seals and gas lines. These are more common in old engines--newer ones usually have newer materials accounting for the problem. Some older gas tanks made of resin actually have dissolved in the presence of ethanol.

Ethanol in pump gasoline has been common in the Midwest, but more recently is distributed nationwide, hence in some areas this is new, others it is long past. Newer areas have experienced an additional problem--when the solvent nature of the ethanol dissolves some stuff that clogs filters, etc., when it is first introduced into the distribution system.

I would think any electrolytic problems are a result of the tendency to adsorb water--an indirect outcome. The stuff is now a mainstay in gasoline nationally, hence is something you have to live with.

[BrianW]

Blue Stabil and Sea Foam.

Got it!

Good thread.

[jonboy]

One other advantage with ethanol/ methanol not mentioned, is, it is miscible with both water and oil/petrol/gasoline. So problems with water in the fuel tank from condensation or filling up at a gas station when the tanker is replenishing the station's tanks or just water in the whole supply chain or letting the fuel tank get empty, picking up droplets and sludge is sometimes solved by putting about 2-300 ccs of alcohol to a full gas tank...it will mix the water and gasoline together. 1% is a good rule of thumb

[Venchka]

Stabil Blue Marine? Sea Foam? Star Tron? Is there a clear winner?

They all say 1 oz per 10 gallons of gasoline. Yikes! I mix 1 gallon at a time. That will be tricky.

[AstoriaDave]

Stabil Blue Marine? Sea Foam? Star Tron? Is there a clear winner? They all say 1 oz per 10 gallons of gasoline. Yikes! I mix 1 gallon at a time. That will be tricky.Can't vouch for the others, but the BLUE Stabil is one oz/5 gallons. Twice that won't hurt anything. Get a small bottle cap and dedicate it to the Stabil bottle, or use the handy measuring system they have and deal out a fraction of an ounce. One you see the Stabil bottle, it will be clear what to do to get a fraction of an ounce.

[Venchka]

Thanks! That would make the Stabil a winner for me.