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MG Midget and Sprite Technical - Ethanol in Esso fuel

Dont know if anyone else has noticed but I normally use Esso super unleaded in the midget from my local station and up until now it has been ethanol free in most parts of the country. When I filled up the other day I noticed the pump now has an E5 label on both standard and super pumps so I assume they are now adding it to super down this way.

T Mason


I noticed the same for the last month or so.

Dave O'Neill 2

from esso web site

What is the ethanol content of your fuels?

The majority of unleaded 95 Octane petrol sold in the UK contains up to 5% ethanol as required under the Government’s Renewable Transport Fuels Obligation (RTFO).

There is currently no requirement for renewable fuel (such as ethanol) to be present in super unleaded (97 grade petrol).

Esso super unleaded petrol (Synergy Supreme+ Unleaded 97) is ethanol free (except in Devon, Cornwall, the Teesside area and Scotland). We would therefore advise anyone who has concerns about the presence of ethanol in petrol to use Synergy Supreme+ – providing they do not fill up in Devon or Cornwall, the Teesside area or Scotland.
mark heyworth


the stickers are there to show that the fuel may contain up to 5/10% ethanol. It doesn't mean it does contain ethanol.

Here's the response from Esso last month.

"Dear Sir,

Thank you for contacting Esso Customer Care.

I can confirm that the information is still valid. (that Synergy Supreme+ contains no ethanol in most parts of the UK)

You may notice new E5 stickers on the Synergy Supreme+ petrol pumps. They are introduced to ensure Esso complies with the Government’s standards on labelling of fuel – see The E5 label means the fuel could contain up to 5% renewables such as ethanol.

Our colleagues have confirmed that Esso does not currently have any plans to introduce ethanol into the Supreme+ fuel brand in the area.

Thank you for your interest in our products. We hope you continue to give Esso the opportunity to be of service to you in the future."

Jeremy MkIII

Yeah, the stickers are a new thing on all pumps at all stations. Some change of legislation relating to renewable fuels that I forget the details of!
Malcolm Le Chevalier

Yet more ill thought out government policy then. We shouldn't be surprised I guess. Seems ridiculous to have to put a sticker on the pump if it doesn't contain any.

T Mason

We are just back from France. There you can use a pump that boasts E85 at about one third the price of the usual petrol. Scary. Fortunately E5 is still common. I don't know if any of the types over there are ethanol free.
Mike Howlett

What's the problem with Ethanol?

It attacks rubber fuel lines and seals and O rings; these decompose over time (a much shorter time than the original service life) unless you go through the fuel system and replace everything with the latest spec materials which are (supposed to be) ethanol-proof.
David Smith

So if Ethanol does become more universally introduced, it's not an insurmountable problem.
From the comments I was thinking perhaps there was something more fundamental involved.

Ethanol rots your teeth and gives you joints problems I am living proof - although I'm not sure I put it in the Midget I do the twice a year I fill the fuel tank on my wife's car.

Thing is -
. could - doesn't mean it does,
. "up to 5%" can include zero/nil/nought/b*gger-all.

I've never had any problems (that I know of) on the Midget from the ethanol, that might or might not be present in the fuel I use, however I've had lots of problems from piss-poor rubber products including fuel hose.

However -
I do believe that the government of this country is out to get some of you good people on here so I am going to give these victimised people up to £1,000 each. :)
Nigel Atkins

According to this the level is to increase to 10% from Jan 20 and we're all doomed!

All sounds a bit 'Broquet' to me.

John Payne

I think I Mr Graham, he's a good bloke, he's a retired Army General from Nigeria.

Nigel Atkins

Ethanol is a solvent as well as being hydroscopic (attracts water). The impact on classic cars is therefore as a solvent on rubber and component parts like ally and brass on carbs over time. It can also impact on fibre glass. Of course the impact on different materials varies so rubber components like fuel lines will be more quickly effected than metal parts. That's why rubber fuel lines should be replaced with ethanol resistant varieties and the lines checked for cracking as part of an inspection routine. (see classic car weekly this week where a TR3 went up in flames over a failed rubber fuel line).

The hydroscopic effect means mild steel fuel tanks can rust on the inside if fuel is left for some time. its not clear how long its takes for corrosion to take hold but keeping a full tank of fuel when overwintering or draining it all or most of it out could be a solution. Of course an additive now widely available may help counteract the effects of ethanol.
Bob Beaumont

I second Bob's thoughts. For cars that do low mileages, keeping ethanol fuel in the tank is not a good idea. The fuel will degrade much more quickly than petrol and after a winter's lay-up could be almost useless. Of course "rubber" components can be swapped for more resistant materials. I have no data on the corrosion of metals like aluminium and brass.

But another thing that gets me is why are we growing crops to feed cars when millions in the world are starving?
Mike Howlett

We have had to use the 10% ethanol fuel blend for quite a number of years in my area of the US. I have had no problems with my MGs, nor my older American made truck. Most of the modern fuel hoses are resistant to ethanol, perhaps because we have had to use it for so many years now. There are reports that a petroleum/ethanol blend does not provide as good a fuel mileage as a pure petroleum blend. I was able to put that claim to the test, last year, when I went up to see my younger daughter graduate from college in the Midwest. There were several states that did not require the use of the E10 fuel mixture and I was able to test the mileage figures for several tanks of pure petroleum vice the more common E10. The test did not show any significant difference between the two fuels in the Toyota pick up truck I was driving.

The point about the fuel going "off" more quickly with E10 is valid. Fuel stabilizer, however, seems to mitigate this problem on cars that are not driven frequently. On regularly driven vehicles, I have never had a problem with the E10.

Les Bengtson

I think I've said this before, but it's worth repeating.

The "driver's handbook" for my 1996 Honda motorcycle states:-

"Fuel system damage or engine performance problems resulting from the use of fuels that contain alcohol is not covered under warranty"

I've had issues with the fuel pick-up pipe in my strimmer dissolving, the carburettor diaphragm in my lawnmower suffering a similar fate, and when I noticed a sudden strong smell of petrol on an MGB that I owned a couple of years ago, I discovered that one of the hoses in the engine bay had become porous.

I now run everything on Esso Supreme, so hopefully it will remain ethanol free for the foreseeable future.

Dave O'Neill 2

there's obviously no disputing the Honda's good book but with the strimmer, lawn mower diagram and that bit of braided hose in the B is there any chance of age, lack of use, Chinese made parts or a combination or permutation of all three that might have contributed to their demise.

I'm sure ethanol has presented some (many?) problems in some situations for some but I feel often it's a scapegoat.

I've only once sampled Esso's fine product and I can't remember if at the time I knew of its purity (fine ales).
Nigel Atkins

ah, Purity Brewery...just down the road here..!
David Cox

This issue just runs and runs. I now run my grass machinery and chainsaw dry, or drain the tank and carb, before leaving them.
Ethanol in the fuel is hygroscopic, drawing moisture from the atmosphere. Most petrol engines are reasonably tolerant to a little water in the fuel (unlike diesels) but the problem is that the ethanol degrades and turns into (I believe) acetic acid.
Aside from the well documented problems with fuel hoses, seals, diaphragms and GRP motorcycle tanks it plays merry hell with Mazak carb bodies. The acid attacks the metal and the resulting oxide has a volume 10x or more of the original parent metal. This stuff gets everywhere. In the last few years I've had this come up time and time again, especially with two stroke outboard engines. Japanese carbs are often very intricate with lots of micro-drillings and tiny passages and they're a pure bastard to clean out. Sometimes it take three or four goes to get them sorted.
Fuel stabiliser additives are supposed to work. I've only recently bought some so I can't comment either way yet, but Briggs and Stratton recommend it for their (four stroke) engines. My new lawn tractor has a 13hp B&S so I'll be trialling the stuff.

In answer to Mike H and his perfectly reasonable question, people are cheaper than cars. Sad but true. Ask Ford for example, with the exploding Pinto gas tank experiment as an example.

For combating the effects of ethanol during long term storage, FBHVC recommend 3 additives:

Corrosion: long-term storage of petrol-ethanol mixtures ( eg over a winter period) can lead to corrosion in historic vehicle fuel systems. Following tests, a number of corrosion inhibitor additives which are effective at protecting fuel system metals have been identified and endorsed by the Federation. These additives are as follows:

The stability additives that passed the test are:

VSPe Power Plus, VSPe and EPS from Millers Oils;

Ethomix from Frost A R T Ltd;

Ethanolmate from Flexolite

More info at

Frost Auto Restoration Techniques' acronym always makes me snigger - it must be deliberate surely?
Jeremy MkIII

This thread was discussed between 22/09/2019 and 24/09/2019

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