E10?

[Pedro_The_Swift]

Following on from Tims post on his John Deere,,
https://www.aulro.com/afvb/general-chat/266907-john-deere-ride-what-petrol-use.html


why do Outboard manufacturers say no to E10?

[Red90]

It eats rubber.

[DiscoClax]

High concentrations of ethanol are also corrosive. But that's way above E10. At E10 levels "most" fuel systems are completely fine, but not all. Really depends on the grades and formulations used for seals, diaphragms, etc. Some manufacturers haven't specifically tested, so err on the side of caution. Others have tested and seen issues. Additionally ethanol-blend fuels shouldn't be used in/as 2-stroke (just like premium in that regard) as it degrades the function of the lubricant.

[JDNSW]

The major issue with ethanol in petrol is not that it eats rubber. The major issue is that it is hygroscopic, that is, it attracts water, and is miscible with water in all ratios.

Petrol is not miscible with water, and water in your petrol tank stays as a discrete layer in the bottom (since it is denser), and is prevented from entering the rest of the fuel system by the gauze filter on the suction pipe out of the tank, which will not pass water drops while it is wet with petrol.

But ethanol, since it mixes freely with petrol, as well as with water, provides a mechanism to distribute water throughout the fuel system. When the engine is not run for a while, the petrol evaporates, leaving the water, which then corrodes the zinc or aluminium allay parts of the fuel system, with the oxide flakes produced blocking narrow passages.

This is a particular issue with outboards, since they operate in a humid environment, ensuring that the any ethanol in the fuel has plenty of water vapour to absorb, and in addition they are typically unused for long periods.

Any small motors that are not in continuous use will have the same issues, but it becomes less of a problem in very dry climates.

[DiscoMick]

If you use mouthwash, it probably contains ethanol, which is why I don't drink it.

[Pedro_The_Swift]

so, unlike cars, an outboard fuel system is open to the atmosphere?

I really dont understand how/why engine manufacturers get away with using bad rubber,, car engines have been fine with ethanol for decades

[rick130]

As JD said my understanding is it's all to do with it being hygroscopic.

Actually am old friend who's business was OPE had a container of e10 mix and left it for a few months to show customers why they shouldn't use it, it wasn't pretty.

[V8Ian]

so, unlike cars, an outboard fuel system is open to the atmosphere?

I really dont understand how/why engine manufacturers get away with using bad rubber,, car engines have been fine with ethanol for decades
All fuel systems vent to the atmosphere, boats operate in a higher humidity.

[Pedro_The_Swift]

all modern fuel systems are closed.
have been for a long time.
so e10 can only absorb whatever air is in the tank, none from outside.

yes they sometimes VENT to the atmosphere(one-way pressure release),,,
usually on very hot days [bighmmm]
like LPG tanks,, except not so explosively[bigwhistle][bigwhistle][bigwhistle]

[DiscoClax]

Ah but a lot of "small engines" in portable equipment (mowers, chainsaws, etc) are still not sealed. Just have a pinhole vent that is two-way. I agree with you regarding cars, etc that they are all fully sealed and have been for a couple of decades, but non-automotive lags behind...

[V8Ian]

all modern fuel systems are closed.
have been for a long time.
so e10 can only absorb whatever air is in the tank, none from outside.

yes they sometimes VENT to the atmosphere(one-way pressure release),,,
usually on very hot days [bighmmm]
like LPG tanks,, except not so explosively[bigwhistle][bigwhistle][bigwhistle]
Air has to replace used fuel so moisture bearing air is being drawn into the tank.

[incisor]

John is on the money honey

[incisor]

And the crap eats more than rubber, it eats some old carburettor bodies as well

[Pedro_The_Swift]

Air has to replace used fuel so moisture bearing air is being drawn into the tank.


no,, is why the caps are pressure rated, is why you get air pressure release when cap is undone.


yes I understand about the absorbment into the fuel,,
and it is irrelevent in modern cars,,

[JDNSW]

all modern fuel systems are closed.
have been for a long time.
so e10 can only absorb whatever air is in the tank, none from outside.

yes they sometimes VENT to the atmosphere(one-way pressure release),,,
usually on very hot days [bighmmm]
like LPG tanks,, except not so explosively[bigwhistle][bigwhistle][bigwhistle]

I'm afraid you are not strictly correct. They do not allow outward venting, except, as you point out, to relieve excess pressure when hot. But they must allow inward venting, as otherwise, by the time the tank was empty, it would have a pretty good vacuum in it, and fuel delivery would be difficult!

The air that is drawn in will contain water vapour, which will be absorbed by the ethanol. If the tank is only partly filled, cool temperatures overnight will mean more air will be drawn in, which will then expend during the day, probably requiring pressure relief, and the cycle repeated next night, with fresh, moist air.

The only way to avoid this is to keep the tank completely full.

As I pointed out above, if there is no ethanol in the fuel, if the air is moist enough, and there is a sufficient temperature cycle, the water vapour in the air will condense on the cold top of the tank, from where it will run to the bottom of the tank. Since it is immiscible with and denser than petrol, it will form separate droplets in the bottom of the tank, that cannot progress further into the fuel system, and hence are largely harmless, although owners of Series vehicles with rusted out fuel tanks or rust pinholes in the suction line may not agree!

[DiscoClax]

In a modern (?... since early 70s) petrol car system the vapour pressure in the tank gets vented through the carbon canister to atmosphere. Theoretically that scrubs out all of the volatiles and nasties. The engine draws from the carbon canister at times low load, high vacuum) and essentially recovers this vapour and burns it. So, yes, strictly not "fully sealed" as I previously posted. I had my emission hat on. True that the tank draws in ambient air as the level drops or it cools, via the cap typically, but some via the carbon canister.
However none of this is hugely relevant to an old JD mower which just has an equalising pin hole in the cap (or one way valve in later stuff) and not much else...
E10 won't eat metal and is likely more beneficial than harmful in general. Holds the moisture in suspension and stops it pooling and coming through in slugs, or rusting your old tanks... also cleans the system. You need to get up a lot higher than that before that's remotely a concern for poor grade metals and 50%+ for anything decent (OEM). For E85 we needed to change rubber composition, change gal steel to stainless, and fit fuel composition sensors for engine tuning. For E10 we did nothing all. That was on a late model car sold globally.
It used to be recommended that you add a cup full of metho to your full petrol tank regularly, esp for outback travel. Back in the days of steel tanks and carbies. Call that about 0.5%. Low concentrations are safe and beneficial. High concentrations require reengineering to work properly and reliably. Where that tripping point is depends on how the engine and fuel system was built and specified.

[Pedro_The_Swift]

My 45L side PULP tank is (assumed ) mild steel, it pops and bangs regularly[bigrolf]

[ramblingboy42]

...and so....getting back to the question......my ride uses e10, its not a John Deere, the engine is 38hp Kholer . My neighbour's is a Husqvarna , similar power and he uses e10. Do JD make their own engines?

[Eevo]

i wont use e10 in any of my cars or chainsaw. it's just not fuel.

[Vern]

i wont use e10 in any of my cars or chainsaw. it's just not fuel.I use it in my brand new patrol. No issues at all.
If it's not fuel, then what is it?

[Pedro_The_Swift]

and the original question is why marine outboard engines are specced to NOT run on E10,, [biggrin]

I think the JD ride ons are rebadged Briggs and strattons [bighmmm]

[Slunnie]

...and so....getting back to the question......my ride uses e10, its not a John Deere, the engine is 38hp Kholer . My neighbour's is a Husqvarna , similar power and he uses e10. Do JD make their own engines?

Don't think so, I'm pretty sure they're all bought in . My JD has a Kawasaki motor but sounds like its B&S now?.

[DiscoClax]

and the original question is why marine outboard engines are specced to NOT run on E10,, [biggrin]

I think the JD ride ons are rebadged Briggs and strattons [bighmmm]IME most marine outboards are 2-stroke. That'd be your answer, right there. Alcohol fuels don't carry the oil well and you'll have lubrication issues. Simple as that.

[bblaze]

IME most marine outboards are 2-stroke. That'd be your answer, right there. Alcohol fuels don't carry the oil well and you'll have lubrication issues. Simple as that.

Na, most of them are now 4 stroke these days you would be lucky to buy a two stroke
cheers
blaze

[Pedro_The_Swift]

twice the size, twice the weight, half the HP,, [bigrolf]

[tact]

I'm afraid you are not strictly correct. They do not allow outward venting, except, as you point out, to relieve excess pressure when hot. But they must allow inward venting, as otherwise, by the time the tank was empty, it would have a pretty good vacuum in it, and fuel delivery would be difficult!

The air that is drawn in will contain water vapour, which will be absorbed by the ethanol. If the tank is only partly filled, cool temperatures overnight will mean more air will be drawn in, which will then expend during the day, probably requiring pressure relief, and the cycle repeated next night, with fresh, moist air.

The only way to avoid this is to keep the tank completely full.

As I pointed out above, if there is no ethanol in the fuel, if the air is moist enough, and there is a sufficient temperature cycle, the water vapour in the air will condense on the cold top of the tank, from where it will run to the bottom of the tank. Since it is immiscible with and denser than petrol, it will form separate droplets in the bottom of the tank, that cannot progress further into the fuel system, and hence are largely harmless, although owners of Series vehicles with rusted out fuel tanks or rust pinholes in the suction line may not agree!

Its not just in your own fuel tank that there can be a phase separation problem....
Veeder-Root | Phase Separation (http://www.detectphaseseparation.com/phase-separation.php)

[DiscoMick]

i wont use e10 in any of my cars or chainsaw. it's just not fuel.Our Mazda 2 is totally happy on E10.
You could get an electric chainsaw.

[trout1105]

twice the size, twice the weight, half the HP,, [bigrolf]

More importantly twice the lifespan and the don't oil up the plugs at low speed[bigwhistle]

[DiscoClax]

Na, most of them are now 4 stroke these days you would be lucky to buy a two stroke
cheers
blazeOooooh. I AM out of touch. Cheers Blaze. I should have updated my knowledge before posting rubbish...

[Eevo]

Our Mazda 2 is totally happy on E10.
You could get an electric chainsaw.
cause ita a low performance engine. you couldn't tell the different anyway. [bigsmile][bigwhistle]
electric chainsaws are awesome

[trout1105]

Na, most of them are now 4 stroke these days you would be lucky to buy a two stroke
cheers
blaze

I just come back from a 4 month trip to King Ash Bay in the gulf and I saw hundreds of different types and sizes of boats there and I would guess that at least 90% of them had 4 stroke outboards on the back of them.
However most of the smaller tinnies had a 2 stroke on the back, Most likely because they are a lighter motor.
My old 12 foot tinny has got a 8-10 year old Evinrude 15hp 2 stroke on it and it still goes like a rocket and my 5.4m Trailcraft has a Suzuki 115hp 4 stroke fitted.
I refuse to use E10 in either engine .

[DiscoMick]

cause ita a low performance engine. you couldn't tell the different anyway. [bigsmile][bigwhistle]
electric chainsaws are awesomeNo it's not, it's from their latest very efficient Skyactive range - goes really well and uses 5 l/100ks on the highway, all on E10.

[bblaze]

I just come back from a 4 month trip to King Ash Bay in the gulf and I saw hundreds of different types and sizes of boats there and I would guess that at least 90% of them had 4 stroke outboards on the back of them.
However most of the smaller tinnies had a 2 stroke on the back, Most likely because they are a lighter motor.
My old 12 foot tinny has got a 8-10 year old Evinrude 15hp 2 stroke on it and it still goes like a rocket and my 5.4m Trailcraft has a Suzuki 115hp 4 stroke fitted.
I refuse to use E10 in either engine .

Agree
I have still got a 18hp tohatsu on my 12 foot tinnie. I once drove past a servo out in a country town because they only had e10, well bugger me I run out of fuel about 1km from the next town. Lotta tears ago, don't think I would be so stubbing now

[drivesafe]

Hi again folks and for a mechanically challenged person like me, two VERY interesting threads.


So here is a more detailed reason for my original question.


During my first summer in my ( 18 years ago ) new Gold Coast home, I quickly found I had no hope of mowing the large and very steep block so I bought the John Deere ride-on.


This took care of the grass but I still needed to do the edges and such.


After a couple of years I decided to get someone in to do the lot.


The ride-on then sat unused for a few years until my father-in-law, because of his age, found it was getting harder to use his push mower, so on a trip over to his place in north west NSW, I took the ride-on over to him.


He passed away a short while back and the mower has just been returned.


Thanks to his maintain acne of the ride-on, it is in a better condition then when I took it to him, so I want to keep it in good nick, and hence why I asked about using 98 petrol.


In addition to this, as I posted in the other thread, I have always fuel all my other gear with 98.


The JD has a Briggs and Stratton motor and I like being able to carry one type of fuel for all my gear, including my Tiguan.


This simplifies what is needed to cover critical weather situations.


I actually have some questions about how to be prepared for critical weather situations but I will start a seperate thread for that.


Thanks for all the info.

[Roverlord off road spares]

Following on from Tims post on his John Deere,,
John Deere ride-on, what petrol to use? (https://www.aulro.com/afvb/general-chat/266907-john-deere-ride-what-petrol-use.html)


why do Outboard manufacturers say no to E10?

Because unlike cars you cant pull over and call road side assist or walk home. you don't want if eating your fuel lines out on the water far from home. my tank lines are synthetic

[Eevo]

No it's not, it's from their latest very efficient Skyactive range - goes really well and uses 5 l/100ks on the highway, all on E10.
all 85kw?

[DiscoMick]

Plenty for the size and weight, with an excellent six speed auto.

[Vern]

cause ita a low performance engine. you couldn't tell the different anyway. [bigsmile][bigwhistle]
electric chainsaws are awesomeOur patrol runs on e10 too, can't tell the difference between e10 and 98, and it's no slouch, 400hp 5.6L v8.

[bsperka]

Fyi: E10 has about 3% less power than straight petrol. 90kj for ethanol; 120kj for petrol. 10% ethanol works out to about 3% reduction.

[trout1105]

I inadvertently put E10 in my V8 D2a once and it ran like Crap and used much more fuel per 100k's[bigwhistle]

[DiscoClax]

Do it once on an older vehicle and that's typically what happens. You just cleaned your fuel system aggressively and pulled all the crud through.

[ramblingboy42]

Sooo, I think what I'm picking up here is not to use e10 as the base for your 2 stroke mix.

I guess the next choice is 95ron for 2 stroke mix?

What fuel are forum members mixing their 2stroke with?

[Eevo]

Do it once on an older vehicle and that's typically what happens. You just cleaned your fuel system aggressively and pulled all the crud through.
[bighmmm]

[Pedro_The_Swift]

I inadvertently put E10 in my V8 D2a once and it ran like Crap and used much more fuel per 100k's[bigwhistle]


jeesus,, I once HAD to put 95 (one pump servo) in the BSL and it pinged its head off just pulling the caravan out of the servo,, ran back inside and bought a octane boost thing and all went fine after..

[Geedublya]

Sooo, I think what I'm picking up here is not to use e10 as the base for your 2 stroke mix.

I guess the next choice is 95ron for 2 stroke mix?

What fuel are forum members mixing their 2stroke with?

95 or non ethanol 91.

[DiscoMick]

There is a 94 E10.

[DiscoClax]

All E10 sold in Oz is 94 RON minimum. It's the cheapest higher octane fuel you can buy.

[rick130]

All E10 sold in Oz is 94 RON minimum. It's the cheapest higher octane fuel you can buy.And the work Hilux goes further and with more verve on e10/94 than when I've used 91.

I still refuse to use e10 in my chainsaw though. [emoji23]

[DiscoMick]

I use electrons in my chainsaw - much cheaper.

[bblaze]

I use electrons in my chainsaw - much cheaper.

Make sure you wear ya earmoffs and chaps
cheers
blaze

[Eevo]

I use electrons in my chainsaw - much cheaper.

whats the bar size?

[incisor]

Make sure you wear ya earmoffs and chaps
cheers
blaze

was waiting for that one....

[DiscoClax]

Almost all petrol engines in the last 20 years are spark limited. They need 95RON + to not pull spark timing down low. In some cases they are tuned for 98RON and that's doubly so. Aggressive timing plus higher compression ratios for emissions and efficiency means they need high octane to work best. Basically if your engine has knock sensors then it wants high octane to work well. Sure it'll run on 91. No worries. It'll lose some low end torque and be a bit doughy but still drive fine. You won't even notice unless you change fuels and feel the difference. Modern electronics and a lot of calibration will see to that.
E10 is even cheaper than 91 and makes cars drive like they are on more expensive 95 PULP. In most cases the fuel economy difference is negligible and in all cases the cost per km is better on E10. What's not to like about that? The mythical 3% economy loss on E10 only applied to dumb old engines that can't retune for the fuel (technically it's around 2.5% by energy density). Anything with knock sensors will love it and give you that back, and more.

In the US they use AKI for their "octane" rating. Anti-Knock Index. That's MON + RON / 2. Simple as that, just an average. In Australia, and most of the rest of the developed world, we use RON. Research Octane Number. MON (Motor Octane Number) is lower than RON so AKI is also lower than RON. 91 AKI is about 95-96 RON, for example. The Yanks base fuel is 87-88 AKI which is equivalent to our base 91 RON. In much of Europe you can't even get anything less than 95RON. 91 is looked at as a poor fuel not worth using. I generally tend to agree...

[rick130]

I use electrons in my chainsaw - much cheaper.


whats the bar size?

I don't think a battery operated saw has been made yet that'll pull a 30" bar in Box. Yet. [bigwhistle]

[Slunnie]

Sooo, I think what I'm picking up here is not to use e10 as the base for your 2 stroke mix.

I guess the next choice is 95ron for 2 stroke mix?

What fuel are forum members mixing their 2stroke with?

Been using E10 for years in 2stroke edger, mower and hedger. Amazingly, everything still works.

[vnx205]

There are good reasons to avoid E10 in outboard motors, but those reasons don't apply to most cars.

My SV21 Camry has done 4 or 5 hundred thousand kilometres on E10 with no problems.

I was once told I would get better power and economy with premium unleaded. I tried three consecutive tanks of premium and the fuel consumption was identical to the figures I got with E10.

[DiscoMick]

whats the bar size?Wide enough for a fridge and stools.

[Eevo]

Wide enough for a fridge and stools.

i'll bring the vodka

[JDNSW]

Almost all petrol engines in the last 20 years are spark limited. .......

That may apply to car engines, but definitely does not apply to the small engines that are the subject of much of this discussion!

[DiscoClax]

That may apply to car engines, but definitely does not apply to the small engines that are the subject of much of this discussion!

Fair call, John. I was thinking automotive rather than the original subject of this thread. I certainly agree that small engines are a very different animal.