new petrol - an idle thought

[Grumpy21]

I've seen quite a few reports of engines running rough lately, sooty plugs and lumpy idling. A friend bought a new lawnmower because his old one wouldn't run right, mine has become hard to start. Both just had sooty plugs and stale fuel.

Every spark plug I've looked at recently has been more sooty than I would expect.

Infrequently used classic cars and lawnmowers may well have petrol sitting in their tanks for several months between fills (not all I know) .

I wonder if there is some connection between the age of petrol, its volatility and propensity to soot up the combustion chamber. I run all my oldies on e5 but with the fuel situation how much ethanol is in the petrol and does it go off?

I'm also wondering if one of the petrol additives might help?

[myoldjalopy]

Articles written on this subject suggest E5 should be OK. I've been running on E5 for several months now without problems so far (except the additional expense ) I am usually out on the road at least once a week.

[kevin s]

Ethanol absorbs water when it is stored, most petrols also loses its volatility over time as the volatile components evaporate off first. A fresh gallon in the spring should be OK for lawn mowing over the rest of the summer.

[Sleeper]

" Ethanol absorbs water when it is stored, " , in an airtight container ?

John ;-)

[Chipper]

Our mower, only a couple of years old and used last year, was very difficult to start last week, having been sitting over winter.

[Bowie69]

Mine had water in the carb, dry shed, never used in the rain.

New carb needed.

[kevin s]

" Ethanol absorbs water when it is stored, " , in an airtight container ?

John ;-)

For it to work a mower would need a breather hole in the fuel tank (usually in the cap) with temperature changes it will draw air in.

[alanworland]

I'm into stationary engines and after a run always run the float chambers dry and drain and dry the tanks. Petrol is stored in unvented container's.
I recently emptied the 3 year old petrol into my modern (24 year old Astra) which used it without any noticeable effects. This was also in an unvented Jerry can.
I understand Esso's Synergy Supreme 99+ is ethanol free.

Alan

[ampwhu]

ive only used shell v power since all this E10 came out. My car runs great.

[Sleeper]

This may help...

https://b3cfuel.co.uk/about-fuel

I think I'm starting to suffer , for the first few minutes of running...no power ...clears after a mile or so...

I suppose the moral of this story is , if you're using it regularly use whatever you want , if not so , use Shell V-Power,BP Ultimate or Tesco momentum etc.


John ;-)

[KeithL]

My Anti-Virus is flagging that page as a known dangerous page and not to visit it.

[Sleeper]

If anyone else complains, I'll copy and paste the wording...

John ;-)

[Sleeper]

Here you are , sorry no pretty pictures...

ABOUT FUEL

Phase Separation

Ethanol is a hydrophilic compound. It is hygroscopic, which means it naturally attracts water. ( which is a major problem in Manchester )
Therefore, when water enters a tank containing an ethanol blended fuel, (either via natural means or through contamination/intrusion), the water will eventually be absorbed by the ethanol.
Once critical mass is reached Phase Separation can occur.

How Phase Separation forms
Water in the tank will continue to be absorbed into the ethanol-blended fuel until it reaches a saturation point. With E-10 fuel at 15°C, this saturation point is at approximately 0.5% water to the volume of fuel. Once the blended fuel reaches this saturation level, the ethanol-water mixture separates from the fuel and falls to the bottom, since its density is now higher than the fuel with which it is mixed. This separated layer is commonly known as Phase Separation. The phase separation layer typically contains 3-4 parts of ethanol for each part water. An alternate phenomenon can occur with far less water than that needed for phase separation.

As previously discussed, some of the water will drop directly to the bottom of the tank as it enters. This water will pull some ethanol from the fuel as it passes through it. This water-ethanol mixture will then pull additional ethanol from the surrounding fuel over time, increasing in volume and resulting in a mixture that is very similar to phase separation; this layer is referred to as Partial Phase Separation. Partial phase separation can occur with far less than 0.5% water. The resulting layer may contain less ethanol than normal phase separation, making it more dense.

What are the possible effects of Phase Separation?
Phase separation contains a lot of ethanol, some water, and a small amount of petrol, a typical ratio would be somewhere around 75% ethanol, 20% water, and 5% petrol. This mixture is highly corrosive when compared to pure water or E-10 petrol; there are some concerns that phase separation may even be more corrosive than 100% ethanol. Some tanks may not be compatible with this ethanol-rich, corrosive liquid. Depending on the composition of the tank, phase separation sitting in the tank may slowly deteriorate the integrity of tank walls, increasing the risk of a leak into the environment; glass fibre tanks on motorcycles, etc. are partially susceptibleto this mix.
Beyond the tank, other elements of the storage and fuel system (piping, carburettor, gaskets and diaphragms) may also be at risk where this phase separation mixture comes in contact, resulting in potential deterioration and/or irreparable damage to components.
Failure to recognise, treat and take steps to prevent phase separation can lead to poor running machinery, mechanical failures/damage, which in turn can result in a expensive repair.

Ethanol
What is ethanol and why is it now in my fuel?
Basically - Ethanol is a renewable, domestically produced alcohol fuel made from plant material, such as corn, sugar cane, or grasses. Using ethanol can reduce oil dependence and greenhouse gas (GHG) emissions.

Ethanol causes fuel decay
Ethanol is organic, therefore it naturally contains oxygen. The high levels of oxygen contained within ethanol blended fuels cause them to decay faster, and if left standing for long periods of time, the decaying fuel will leave varnish and sludge deposits.
Think of it this way - Petrol is now a bit like milk, both are organic - they decompose the same way. A foul, sour smell indicates STALE FUEL! Power equipment not treated with an ethanol fuel stabiliser will become hard to start within 30 days. Petrol can decay in as little as 60 days!

Test
It’s very important to understand the quality of the fuel that you put into your valuable equipment. Whether it be petrol or diesel, the majority of engine problems are due to bad fuel. Our fuel quality test swabs let you know if your ethanol blended fuel is fresh, marginal (decaying) or bad. Knowing your fuel quality is the first step to fixing and preventing your fuel related issues.

Why test your petrol?
Ethanol attracts water; settles on the tank bottom (phase separation) and is pulled in by the fuel line.
Ethanol blended fuels can decompose in as little as 60 days.
Severe engine damage can occur when run on marginal fuel.
Damage can include carbon, varnish, rust, gumming, brittle and broken rubber and plastic parts, corrosion and much more.


Done...

John ;-)

[KeithL]

Thank you John. Very interesting.

[Sleeper]

Sadly the fuel is fed from the bottom of the petrol tank , where the water collects , have been looking how to rid the fuel of water and have decided on a Malpassi Filter King , the filter element is 10 Microns ( blocks water molecules ) and any crud , glass bowl so one can see the water ( hopefully ) , just missing a drain tap , so will drain the bowl when necessary.
Set at 2.7-3psi for the intended HIF44

John ;-)

[kevin s]

I was working on my tr7v8 at the end of last year, took me a few minutes what was going on with the "air bubble" in the bottom half of the fuel filter!

Never seemed to affect how it ran though.

[Sleeper]

Kevin

" Never seemed to affect how it ran though. " " the "air bubble" in the bottom half of the fuel filter "

No it won't ,as I believe the fuel is fed from the top of the filter.

John ;-)

[kevin s]

It's one of those plastic ones on it's side, and it was up to the middle which I think means some would have gone in. Poor man's water injection!

[dp]

There's a motorbike youtube channel that explains it quite well.

https://www.youtube.com/watch?v=ZRNfyz1Cgvg

If you don't want the build-up skip straight to 6.30.