Ethanol test for pump petrol

[Luddite]

Further to posts on this earlier thread:

http://www.ukmonster.co.uk/monster/s...ad.php?t=54410

There is a lot of conflicting information, (and misinformation), out there on the web about which fuels may or may not contain ethanol. One thing I think we're all agreed on is that ethanol is not good news for our bikes, whether they are old 'uns with carbs that can be damaged/gummed up or newer models with plastic tanks, which may suffer distortion. We need to know the ethanol content of our fuel so that we can make an informed choice.

We're not helped in this by the fact that there is no requirement for petrol stations to show ethanol levels on the pumps.

The present position is that, under BS EN228, petrol can contain up to 10% ethanol. There is no minimum amount and no requirement to display the ethanol content. So fuel could contain anything between zero and 10% ethanol; there's no way of knowing at the pump.

At the moment, until 31 December anyway, there is a legal requirement for petrol companies to provide 'protection grade' fuel with no more than a 5% ethanol content. This is usually the super unleaded fuel but, as with the regular fuel, there is still no way of knowing whether it contains zero or 5% ethanol or something in between.

One of the (many) problems with ethanol is that it is hygroscopic i.e. it absorbs water. In practical terms that means, if you leave a tank of fuel containing ethanol for any length and time, it will bond with the moisture in the air and, once it has absorbed enough water, it will come out of suspension with the petrol and sink to the bottom of the tank (because water is heavier than petrol). This is called 'phase separation'.

Once at the bottom of the tank, it can promote corrosion, gum up fuel systems or cause plastic tanks to swell.

This process of phase separation is how proprietary ethanol removal kits like 'Ethanil' work; just add water to the fuel, wait for separation then drain off the water/ethanol mix, leaving you with neat petrol.

I thought I'd use that process to check whether the Esso Super Unleaded was, in fact, ethanol-free as I had believed.

[Luddite]

First of all, I checked some regular unleaded, which I knew should contain ethanol, just to make sure the process worked.



First, I poured 220ml of unleaded into a measuring cylinder then added 30ml of water. Being heavier, the water sinks to the bottom. You can see the boundary line in picture A. I then shook it up to mix in the water and left it for 30 minutes. You can see in picture B that phase separation has taken place, the ethanol has come out of suspension with the petrol, bonded with the water and sunk to the bottom. The boundary line has risen from 30ml to 40ml. This certainly proves there's ethanol in this unleaded and suggests a level of about 4.5%.

Knowing that the process works, I then tried the same thing on identical quantities of Esso super unleaded. Here are the pictures:



Well that's reassuring! Absolutely no change whatsoever. The boundary line, as before, started at 30ml and, after a full hour (just to be sure), was still at 30ml.

This is an easy test with no special equipment needed so, if you've got any doubts about your own petrol supply, why not try it yourself?

I found this aticale and it gives a list of Super Unleaded that do and do not contain Ethonol http://www.groups.tr-register.co.uk/...ol-update.html
Worth a look.

Pete.

[uncle duke]

Yeh always worried about amount of ethanol in petrol (s2r plastic tank) so it was good to see that the super unleaded in your area at least doesn't seem to contain any .How old is the tr register article ?? . so i think its gotta be super unleaded for the bike as i always try to do anyway .

[Mr Gazza]

Good factual article Luddite, and nice graphic demonstration.. Thank you for posting this.

The "TR" article refers to 2013 in the future tense, so we can assume it is pre-2013 at least. Some of the links don't work anymore either, so I think we can assume that some of the info is out of date.?

[Luddite]

Originally Posted by Fat Pete

I found this aticale and it gives a list of Super Unleaded that do and do not contain Ethonol http://www.groups.tr-register.co.uk/...ol-update.html
Worth a look.

Pete.

I've referred to that article myself, Pete. It's been very useful but it's been around a few years now with no updates so I'm not sure how accurate the list of suppliers and ethanol proportions are. Interesting to see that the Esso ethanol level was shown as 5%, which is the amount I found in my test.

winner you can even drink the 'waste' liquid Yeah

probably cheaper than buying a bottle of vodka ~:?

[Luddite]

Originally Posted by Scotty

winner you can even drink the 'waste' liquid Yeah

probably cheaper than buying a bottle of vodka ~:?

!

My little test on this is when I clean the RSVR Mille over winter.
Ran on BP Super Unleaded all summer and just lifted the tank with no issues, i.e. has not swollen due to ethanol

[MerlinPV12]

Excellent write up on something I had unsuccessfully pondered on, thanks!

[utopia]

Much appreciation from me too.
I've been using BP's expensive stuff in my carby M750 ever since the last big drop in petrol prices (when it became cheaper than the cheap stuff had been, so I used the excuse to "upgrade").
Tried it first in the Dommie and I was amazed to find that I could actually detect a performance benefit .. better throttle response and smoother tickover. It was unmistakeable.
I never buy anything else now but I have wondered whether it is just low ethanol or totally ethanol free.
I became suspicious that it might contain some ethanol on the morning of the Wells fish and chip run, when I suffered the first bought of carb icing for this year, until the dawn air warmed up a bit. I might have expected better of premium grade fuel (though in fairness, it was a damp, claggy morning).
I will now do the test and find out.
Inspirational !

[Kato]

Jeff
Your suspicion of Fuel icing, which is the result of water, held in suspension in the fuel, while probable generally happens only at altitude, a big problem for light aircraft possibly not for a M750 , what you experienced was probably a result of atmospheric conditions and not attributable to ethanol content

Basic fluid dynamics, says that a fluid's velocity must increase as it passes through a constriction in this case your carb’s venturi, causing a big temp drop

Seems that Duke’s suffer this problem a lot so it’s interesting that the Venturi effect is named after Giovanni Battista Venturi, an Italian physicist, however I digress

So the problem is caused by the sudden temperature drop due to fuel vaporisation and pressure reduction at the venturi, there is far more moisture suspended in cool air than in your fuel, the temperature drop may be as much as 30ºC and results in the atmospheric moisture forming ice, this initially blocks the smallest jets and affects the engine at low revs, the more mixture that passes through the carbs, the worse it gets, so riding fast (or revving the engine at a standstill) makes it worse, it’s not just carb’s either as Fi is not immune although nothing like as common

You of course know all this already but still might be useful to others

I agree totally that ethanol is a big problem thats not going away anytime soon, however on this occasion don't think it can be blamed.

This chart robbed from a aircraft forum is quite a nice graphical representation of the issue



In short

*Carburettored engines suffer most from icing because carburettors
cause evaporation, which cools the air.

*Icing can happen at temperatures of up to 38 degrees C.
Paradoxically, it is less likely at very cold temperatures.

*Icing is more likely at partial power settings because of the
cooling effect of a partly-closed throttle butterfly.
Right thats enough thinking for a hungover saturday morning

[utopia]

Yes indeed.
My comments were based on having heard it said that carb icing was less of a problem with premium fuel.
In fact my own experience leaves this question unanswered, but if there is some truth in it, it seemed reasonable to suspect the ethanol content of the regular stuff to be the root cause of its poorer performance.
I wouldn't go so far as to suggest that this is because of absorbed water in the fuel though because, as you say, there is probably more than enough moisture in the air anyway.
Therefore I was thinking that the reason could be that the ethanol might change the vapourisation characteristics of the fuel in much the same way as dosing with pro.fst does, but in the other direction.
This is merely supposition on my part though ... I have no evidence or logic to support it.
I don't even have confirmation that premium fuels are less susceptible to icing at all .. it may be urban myth, but if it isn't then it does seem likely that ethanol is involved somehow.

Anyway, this may be a thing of the past for me as I now have a box containing a shiny new pair of FCR flatslide carbs ... which I am told are far less prone to icing.
This is the hope anyway but I have to confess that once again I only have the experience reported by others on which to base my hope, rather than any hard factual analysis.
The fact that the cables pull directly on the FCR slides rather than via a butterfly/diaphragm system is reassuring though.
Anyway, we shall see.

Sorry for slight hijack there.

Hope the hangover is mellowing, Kato.

[Mr Gazza]

Let's not forget that the octane rating is essentially different between regular and premium by very definition, and have different properties designed in regardless of Ethanol content.
The aircraft icing chart will be based on using Avgas which is 100 octane (possibly 110 octane?)

I remember trying some 5 star in my Honda 50 once.. It sapped the power and got hot.
My Dad kindly explained the meaning of octane ratings and I ran it on 2 star happily ever after.

I always try to put premium or super in my 900 injection and enjoy lots of smooth power and economy (68mpg at a 90mph cruise on a very long private runway).
If I'm forced to use regular I only notice it being slightly less good, but there is a difference.

I did suffer what I assumed to be Carb icing on my carburettor equipped 900 Monster, but the oil fed warmers were enough to fix it once they were turned on. A damp but mild Autumn day was enough to bring it on.... All to do with relative humidity. (see above)

[Luddite]

Originally Posted by Kato

Right thats enough thinking for a hungover saturday morning

There's another problem caused by too much ethanol!

Here's a thought; the reason we're stuck with this ethanol is a European Parliament Directive 2009/28/EC, which requires each member state to be using 10% biofuel by 2020.

Hmm...member states...2020...

Brexit anyone? Aren't we supposed to be out of the EU by 2020?

I mentioned earlier that there is currently a legal requirement for fuel companies to provide 'protection grade' petrol. This requirement runs out on 31 December 2016 and I can't find any details anywhere of what's going to happen after that. I wonder if the delay is as a result of Brexit? If I do find anything out, I'll post it here.