Water in fuel

[Robert Atkinson 2Participant @robertatkinson2]

Dave W beat me to it on ethanol affecting tank coatings. As I mentioned earlier it badly affects some light aircraft tanks. It has some odd effects. Materials that are fine with just petrol or just ethanol can be softened by a mixture of the two.

Robert G8RPI.

[SillyOldDufferModerator @sillyoldduffer]

Posted by RMA on 25/09/2019 18:02:16:

Posted by fizzy on 24/09/2019 21:16:57:

…

…

From the internet research I've done so far, it looks as though the USA are using up to 15% and want to increase this, as do the British government.

…

What I'm trying to find out is the link between standard 5-10% ethanol/ petrol mix ( as bought direct from the filling station), left standing for say 6 months in the tank, and it's effect on metal due to water absorption, that being in the main the submerged fuel pump(s), filters and lines. …

… I might be trying to find the impossible, but a scientific answer is what I'm after.

There have been one or two problems with petrol over the year's which have affected engine… Is the increasing percentage of ethanol in petrol (not Diesel) going to be the next? ( that's a rhetorical question by the way).

I don't think there's a simple answer to this because a great deal depends on the age of the car, the type of engine, local weather, and the various ways water might get into fuel. (For example, rain penetrating the filler cap, wet delivery at a service station due to poor maintenance, condensation risk coupled with owner leaving tank empty for long periods etc. )

Old cars are likely to be more vulnerable than new ones. Cars designed and built more than 20 years ago may be made using metals and plastics that aren't resistant to Ethanol in fuels whilst carburettors mix air, fuel and metal in a corrosive way that injectors totally avoid. Older cars don't get much benefit from Ethanol either because their engines are unlikely to be smart enough to take advantage of Ethanol's anti-knock properties,

Ethanol on its own is capable of damaging certain plastics and metal. Additionally, Ethanol added to petrol could carry water through the fuel pump and pipework and into the float chamber when previously it might have sunk less harmfully to the bottom of the tank. But it's not unlikely that water collecting in the tank of an old car could cause similar damage even in the absence of Ethanol – how often is the petrol tank of a car drained and cleaned?

Petrol itself is also a potential problem. It's a variable mix of hydrocarbons some of which are also capable of causing damage. You don't really know what you get at the pump.

Ethanol / petrol mixes are a good thing in a new car – cleaner burn, better fuel economy, reduced carbon footprint, renewable fuel etc. Ethanol in fuel doesn't worry me, but then I don't own a classic car or bike.

Possible to remove Ethanol from petrol by washing it with water as described here. Not sure it's entirely safe due to toxic fumes and the fire risk…

Dave

[RMAParticipant @rma]

Water injection is well known but it isn't the subject here folks.

Dave W, Robert and Dave have highlighted the fact that I didn't mention I'm talking about old cars, well 18 -22 years old. Components were made to work with the fuels available at the time, and to be fair I doubt anyone could foresee what we have forced on us today. We've had problems with lead free, sulphur and now ethanol.

Governments seem to have a knee jerk reaction when advised by the so-called experts, remember Brown and Diesel? 10% ethanol is not uncommon now, 15% in the USA and they want it increased. This will affect thousands of newish and new cars, let alone the older ones.

The parts I'm referring to are on high end cars and expensive to replace and difficult to diagnose until there's a failure. It seems no one on here can come up with the answer I'm seeking and that's fair enough, just have to keep searching the net.

[CirclipParticipant @circlip]

I remember an article in The Motorcycle back in the sixties showing a water bleed conversion of a Carb. on a single cylinder bike.

Regards Ian.

[SillyOldDufferModerator @sillyoldduffer]

Posted by RMA on 26/09/2019 10:27:21:

…

The parts I'm referring to are on high end cars and expensive to replace and difficult to diagnose until there's a failure. It seems no one on here can come up with the answer I'm seeking and that's fair enough, just have to keep searching the net.

I thought my idea of washing the petrol at home with water was a bit dangerous using improvised utensils but this Ethanil Kit provides the wherewithal. Main problem is it needs several minutes of vigorous shaking followed by about 90 minutes settling time to produce 6 litres of clean petrol. The process could be scaled up but I believe the volume restriction is a legal requirement. The law discourages amateur meddling with large volumes of petrol because it's a serious whoof-bang fire risk!

I see the kit allows the ethanol content of petrol to be estimated, probably with a hygrometer. That would allow purchasers to identify and avoid buying high-ethanol fuels at the pump.

Treated and untreated fuel could be mixed to reduce the amount of work and time involved in cleaning the petrol. 6 litres of untreated E5 petrol (5% ethanol) plus 6 litres of treated E5 would half the amount of ethanol in the mix, thus reducing the risk of damage.

Otherwise alternating tankfuls of treated and untreated fuel might be a workable strategy. Always going into storage after a good run on treated ethanol free fuel would keep the car's internals flushed and clean most of the time. For example. an entire tankful of E10 consumed in a 5 hour blast up the motorway wouldn't have time to cause much damage compared with leaving the car parked for several weeks in a garage. Driving mostly on pump petrol whilst making sure the car is mostly ethanol free off-road might be a manageable compromise.

Dave

[Ian S CParticipant @iansc]

Part of the daily inspection of a light aircraft is to check the fuel forOne rule is to keep the fuel tank full, this helps to minimalise the build up of water in the fuel system. If the plane is parked up over night with partly empty tanks quite a bit of water can form as condensation.

Ian S C

[Robert Atkinson 2Participant @robertatkinson2]

Washing the ethanol out with water is pointless in this context because the washing will leave MORE water in the petrol than before. It seems pointless to me anyway.

Just looked at the ethanil kit £50 for a clear fuel can with a drain tap! And how do you dispose of the petrol contaminated water ethanol mix?

Not all old cars have the issue with modern fuels. When unleaded was starting to be introduced in the mid to late 80's it was a lot cheaper than regular leaded (usual tax incentive to lull us into a false sense of security) I had a 1975 Jensen Healey and used to use unleaded, if the cashier would let me! They could not believe that a 10 year old car was OK on unleaded and often took some persuasion to turn on the pump. The JH had a Lotus 907 2l, a modern design and the one I had was a LHD Californian spec example that was specifically meant to run on unleaded.

Edited By Robert Atkinson 2 on 26/09/2019 12:46:41

[VicParticipant @vic]

I’m not sure old cars are really going to be a problem anyway as I’m sure they are going to be banned from our roads altogether in the not too distant future.

[JAParticipant @ja]

Posted by RMA on 26/09/2019 10:27:21:

Water injection is well known but it isn't the subject here folks.

Thank you. I have been trying to prevent myself from posting something on water injection.

Major problem with fuels is that the refiners and distributors do not have to tell you what is in the fuel. This includes additives. All the fuel has to do is to meet the specification.

About 12 years ago there were a spate of cases where a fuel additive was destroying an engine sensor and thus engines. I think the fuel suppliers legally hid behind the fact that their fuel met the specifications.

There are firms out there, such as Carless, who will blend a fuel to your specification. We used them at work. Obviously they will not put in banned additives such as tetra-ethyl lead and they will only deliver in bulk. You will have to be able to store it legally and pay tax (VAT and vehicle fuel duty).

Addition – I am sorry to say Vic is probably right. They know who you are – You don't pay road tax and your vehicle does not need an MOT.

JA

Edited By JA on 26/09/2019 14:00:06

[SillyOldDufferModerator @sillyoldduffer]

Posted by Robert Atkinson 2 on 26/09/2019 12:43:58:

Washing the ethanol out with water is pointless in this context because the washing will leave MORE water in the petrol than before. It seems pointless to me anyway.

Just looked at the ethanil kit £50 for a clear fuel can with a drain tap! And how do you dispose of the petrol contaminated water ethanol mix?

…

Though it might seem counter intuitive to add water to petrol to remove water, it certainly works!

Ethanol and Water mix together freely as does Ethanol and Petrol. Water and petrol don't mix, but a certain amount of water can be dissolved in an ethanol/petrol mixture because the alcohol acts as a carrier. That's why classic cars might have a problem with modern petrol. Not good if any parts of a car's engine, pipework, carburettor or fuel pump are water sensitive.

Vigorously shaking ethanol-loaded petrol with a significant dollop of water dissolves the ethanol preferentially in the water. When allowed to settle, petrol floats to the top leaving the unwanted water/ethanol mix below to be separated.

There's no problem disposing the waste – in another context water and alcohol make popular beverages. However I wouldn't recommend drinking a 'shaken not stirred' petrol cocktail because fuel alcohol is far from food-grade. Don't blame me if drinking it leaves you blind in hospital with rot-gut!

I agree the cost of the kit is high for what you get, but at least it's designed for the job rather than knocked up by an unwise optimist!

Dave

[MeunierParticipant @meunier]

Just about on-topic
Mid 70's was sitting in a 747 on the ramp at Lagos airport with a guy from the company dispatch giving me a carrier bag full of broken Motorola walkie-talkies to take back to London and watching a chap with a shopping trolley equipped with a jerry-can and funnel. He was using a glass cylinder on a pole to 'dip the sump' of the fuel tanks repeatedly, examining each sample carefully for water content, dumping it into the can and taking another sample. I asked the company guy whether the fuel in Lagos was contaminated ? No, he said, the dipper guy was just being super-efficient, mentioning that the guy was one of the better-off in the villages that surrounded the airport. Naively I enquired whether his job was so well-paid. No was the reply but all the villagers cooked on paraffin stoves.
DaveD

[Howard LewisParticipant @howardlewis46836]

To detect water in storage tanks, we smeared the end of the dip stick with a product called Bluchalk.

If the end of the stick was white when withdrawn, water was present. Then tank was drained until it looked like the water was out, and then you checked again.

I've seen light aircraft checked for water by draining small samples from the bottom of the tank into a glass container. At 1,000 feet ASL is not the place to have an engine cut out!

Howard

[Danny M2ZParticipant @dannym2z]

To reply to the OP.

I am not a chemist but in my desire to remove water from methanol (model engine fuel ingredient) a bit of research led me to investigate zeolite molecular sieves as used by a local biofuel manufacturer to reclaim methanol.

A molecular sieve is basically a substance that has pores that admit molecules below a certain size. So in the case of zeolite the correct grade can admit the small H20 water molecules but the longer carbon chain alcohols are too large to enter the sieve.

A friend who is an industrial chemist confirmed this and also remarked that the zeolite may also be reclaimed for further use by drying in an oven to remove the water.

* Danny M *

[RMAParticipant @rma]

Posted by Danny M2Z on 27/09/2019 07:45:47:

To reply to the OP.

I am not a chemist but in my desire to remove water from methanol (model engine fuel ingredient) a bit of research led me to investigate zeolite molecular sieves as used by a local biofuel manufacturer to reclaim methanol.

A molecular sieve is basically a substance that has pores that admit molecules below a certain size. So in the case of zeolite the correct grade can admit the small H20 water molecules but the longer carbon chain alcohols are too large to enter the sieve.

A friend who is an industrial chemist confirmed this and also remarked that the zeolite may also be reclaimed for further use by drying in an oven to remove the water.

* Danny M *

Interesting info but this needs to be done before fueling the tank and you say the sieve admits water, that's something I'm trying to remove. The problem is actually dealing with the effect of the ethanol/petrol/water mix in the tank. For clarity, the water isn't deliberately put in the tank, it's there because of the ethanol in the fuel.

Obviously whatever method chosen (if there is a good one) will not correct any damage previously done, and that's impossible to see unless the tank is removed and inspected internally for pump damage etc. A major and expensive task as one of our members has just learned and alerted the rest of us!

Conclusion: This winter I'll start using some additive and always keep the tank full as usual, drive my car as normal in the winter as and when (dry sunny day), so it won't get many miles will it, and hope for the best, it's only done 31K in 22 year's anyway. I will in future keep an eye on the fuel composition at the pump, that's if we're allowed to know of course.

[RMAParticipant @rma]

Posted by Meunier on 26/09/2019 17:00:20:

Just about on-topic
Mid 70's was sitting in a 747 on the ramp at Lagos airport with a guy from the company dispatch giving me a carrier bag full of broken Motorola walkie-talkies to take back to London and watching a chap with a shopping trolley equipped with a jerry-can and funnel. He was using a glass cylinder on a pole to 'dip the sump' of the fuel tanks repeatedly, examining each sample carefully for water content, dumping it into the can and taking another sample. I asked the company guy whether the fuel in Lagos was contaminated ? No, he said, the dipper guy was just being super-efficient, mentioning that the guy was one of the better-off in the villages that surrounded the airport. Naively I enquired whether his job was so well-paid. No was the reply but all the villagers cooked on paraffin stoves.
DaveD

Nice one! I often wonder what happens to the samples taken from the main tank at my airfield when we have a delivery. I'll ask around, not sure what Avgas would do to the car.

[SamsarandaParticipant @samsaranda]

Older cars that used leaded fuels used to run ok on Avgas, add a little kerosene to the fuel to bring down the octane rating, not good for continuous use though, intersperse with tank fulls of normal pump fuel. Zeolite is also used in the filter systems of koi ponds to remove ammonia, can be recharged and used again.

Dave W

[Howard LewisParticipant @howardlewis46836]

Avgas was probably higher octane rating than what was available at the roadside pumps.

During WW 2, 100 octane was used to give higher power in aero engines.

The only downside in those days was that some of the Tetra Ethyl Lead anti knock additive could become a lead deposit on the valves. It wasn't until the early 60s that 100 octane road fuel became available, because of the need for cars like the Rover P5. Even today, unleaded "Super" petrol is 97 or 98 Research Octane Number, depending on where you buy. Standard unleaded petrol is 95 RON, at least in UK.

Howard.

[duncan webster 1Participant @duncanwebster1]

When I was a lad petrol came as 2 star, 3 start etc up to 5 star. Despite my strongest arguments my dad always put 5 star in even with fairly low compression engines, it cost more so it must be better.

[Robert Atkinson 2Participant @robertatkinson2]

Posted by RMA on 27/09/2019 09:35:41:

 

Nice one! I often wonder what happens to the samples taken from the main tank at my airfield when we have a delivery. I'll ask around, not sure what Avgas would do to the car.

The samples should be put in a waste container and disposed of properly. Eye witness evidence, stains on the ramp and dead grass on parking areas indicate it is often just dumped.

Avgas is leaded and will kill your catalyst / O2 sensors and is illegal for road use as the corret tax has not been paid. Jet A is not good for modern diret injection diesels du to poor lubricity and i likewise illegal for road use.

Robert G8RPI.

 

Edited By Robert Atkinson 2 on 27/09/2019 20:18:14

[JAParticipant @ja]

I think the latest postings are slowly drifting off subject again but I have been dying to write something.

AVGAS went up to an octane rating of 130. All the piston aircraft engines used by the British and Americans in the War were designed and initially developed before the War. These engines were either naturally aspirated or had a very low boost pressures. The compression ratio was usually about 7:1 and the octane rating of the fuel was 100 or lower. As the War progressed fuels with higher octane ratings allowed the boost pressure to be increased resulting in very large increases in power with no change in compression ratio.

One little question: How do you dispose of waste fuel responsibly?

JA

Edited By JA on 27/09/2019 20:22:57

[mark costello 1Participant @markcostello1]

I have personally seen a foreign cargo jet dumping fuel when close to landing. A descending cloud about 1/2 mile long over Someones farm is kind of hard to miss.

[Jeff DaymanParticipant @jeffdayman43397]

I think that method was invented by a Mr. J. Ettison.

[Tim StevensParticipant @timstevens64731]

That's how you get fuel in your water.

Tim

[CHARLES lipscombeParticipant @charleslipscombe16059]

At long last I have been tempted to weigh in to the ethanol in petrol debate. The "problems" with ethanol fuel seem to have been greatly exaggerated to me. Australia has been using up to 10% ethanol in fuel for many years (10-15?).

In this time I have used it in three Toyotas dating from circa 1980 to 2000 plus in a variety of vintage and veteran motorcycles. I have never had the slightest problem from its use but the oldest Toyota runs a bit more smoothly on ethanol fuel, probably because of a rather poor state of tune.

More to the point is that I have never seen any reports of people having problems with ethanol fuel. Given the normal human tendency to knock anything new -it's not as good as what we used to have- I think it is safe to say that anyone using ethanol fuels is most unlikely to suffer any problems, despite theoretical disadvantages from possible water content and solvent power on fuel lines etc.

I don't include people who are using tank liners or fibreglass tanks in this comment. However being a very cold-intolerant person, my vintage bikes often sit for months in the winter and I have not noticed any rust formation in the tanks.

Maybe the dampness of the climate has an influence but there again I have never heard of problems from the tropical, monsoon area of Australia either

Chas

[SillyOldDufferModerator @sillyoldduffer]

Posted by CHARLES lipscombe on 28/09/2019 04:18:12:

At long last I have been tempted to weigh in to the ethanol in petrol debate. The "problems" with ethanol fuel seem to have been greatly exaggerated to me …

Chas

I think that's a good point! There can't be many places in the world where petrol is alcohol free, standard British petrol is up to 5%, and Premium Grades are likely to be higher. It's not new either – the Model T Ford was designed to run on Alcohol, and many petrols in the 1920s and 1930s contained it.  Hundreds of millions of cars are burning ethanol loaded petrol without an trouble.

I guess the vehicles most likely to have problems are those built during the heyday of Leaded Petrol, say 1950 to 1980. During this period cars rarely encountered alcohol, and their designers might have used materials sensitive to it or the dissolved water it can carry. They weren't designing cars to last, and had no notion they might become 'classics' or that Lead was going to be phased out!

However, by the early seventies it was well known that Lead was done for, making it likely that designers would allow for Ethanol in future. And of course many of the plastics and metals used to make cars are tolerant anyway.

Bottom line, modern cars and very old cars are OK, and there's a reasonable chance 1950 to 1980 won't be effected either. Cars built between 1980 and, say 2000 should be better again.

However, there are a mass of unknowns in this. Well-known that elderly engineers often cling to what worked in their youth and block change if they can. Even more sinister is the dreaded accountant – they like to switch at the point of minimum cost – when all the old-stock has been used up, or not at all if the replacement is more expensive! And the owners will time changeovers to suit the business, which might mean nothing happens until they've relocated the factory. How these factors pan-out in the components used to build and repair an old-car is hard to predict.

I suppose it's unwise to expect cheap straightforward motoring from a Classic Car. Owning one always involves a certain amount of bother. Lead free petrol is another issue, though reasonable substitutes are available. Another problem is long-term storage of petrol in the tank of an infrequently run car. Petrol is 'Best Before' it's 6 months old and it goes off rapidly thereafter causing other problems for engines.

Dave

Edited By SillyOldDuffer on 28/09/2019 10:07:13

[Author]

Posts