Fuel conversion

[Denis]

Hi fellows,

Considering the cost of liquid gold, has anyone ideas on running an M116 engine on ethyl alcohol ?

Obviously the flexible fuel lines need replacement but will the 2 bar pressure regulator survive ?

Production of this fuel is not a problem but setting the engine to run on it (50-100%) is.

Any suggestions ?

Merci ! Bedankt, Danke sehr, thanks ...

Denis

Paris, France

[oscar]

Ethanol seems like a magic bullet.  There's so much info for and against.  I'm all for it and can't believe its taking so long in my country (Oz) to move along with its large scale intro.

HOWEVER!   My 116 will stay away from ethanol blends for some time since I believe the conversion needed would cost too much for the following reasons;

-  I'm sure we've all heard how corrosive it can be.  Because ethanol is a solvent it can attack metal, rubber, and plastic components in a fuel system.  This means fuel lines, injector seals, fuel pump, regulator...the whole system's at risk.   As a solvent, crap in the lines may be dislodged and form blockages.   The components are similar nowadays except they are designed to be compatible with ethanol.

-  Unlike petrol, ethanol dissolves/absorbs water, which can lead to rusting that big 96 litre tank (assuming it's steel).  Apart from holes the rust will travel up the lines and block injectors. Water in the motor would lead to a bit of rough running too.

-  Because of ethanol's high oxygen content the motor may run lean and I wonder if D-jet or K-jet injection systems would be able to adjust the fuel to air ratio to compensate.

Now, of course I didn't come up with all this all by myself, I summarised from a webpage I saved last year sometime when the ethanol debate started to heat up in Oz.  Sorry, don't know the link but plenty out there to read.  The conversion would be too expensive when you look at the cost or difficulty of replacing the tank, lines, pump, filter, seals, updating ecu or k-jet somehow.  As attractive as ethanol is, I wouldn't convert to it myself.

Interestingly, all Mercs post 1986 have compatible fuel systems for ethanol blends and Henry Ford's Model T ran on pure ethanol.  He said ethanol was "the fuel of the future".

[Denis]

Hi mb350

So basically, you are saying that post 1986 hardware (tank fuel pump,etc) would make it easy to run ethanol ?

I have heard of the corrosion issue but am not entirely convinced. The fact that alcohol absorbs water seems to me a good thing in preventing corrosion in the tank.

OTOH, I have heard that mixture issues is easily solved by ignition timing changes, not necessarily FI adjustments.

Regards

Denis

Paris, France

[Bratman47]

Need to find out how the people in Brazil did it as ethanol is their major fuel. They started 10 years ago and now are oil free.

[oscar]

Hi all,

In Australia the current blend involves only 10% ethanol and a list I found had >1986 MB as having compatible systems for this blend.  It does raise the question then about what could be pulled from a  W126 and fitted to our W116's.  I also have no idea what makes these systems compatible.  Fuel tanks aren't steel anymore but are the other components entirely different or just treated?  More web searching to do I think.

With a low 10% blend, deteroration of components, may not eventuate.  With a 50 - 100% mix as you mentioned Denis, I would assume any corrosion would be accelerated.  My car has a 30yr old system that personally I don't want to test its longevity, (not yet anyway).

Re: the absorption of water.   I got the impression that water was attracted to ethanol, rather than absorbed.  Poor choice of word on my behalf.  In other words, water does not change in structure as if being dissolved but would be a free agent to react with metals.

Regardless of these theories, it still remains to be seen just how long it would take for any adverse effects to appear.  The suggestion that ignition timing adjustment to tackle the fuel/air mixture is an interesting idea and I'd like to hear more on what such a change would do.  I simply don't know enough to comment.

As Bratman47 mentioned, Brazil is I believe the world leader in ethanol use (for cars not human consumption)  .  Perhaps Nilo AMG, or any Brazilian, if you're watching, could speak from personal experience of ethanol use (automotive), and any problems.

[Denis]

Hi guys

Look at this :

http://www.chemguide.co.uk/basicorg/acidbase/acids.html

This chemguide says that ethanol is hardly acidic at all.

So is not the problem the fact that there is water in the ethanol (corrodes things) ?

Looking at the production process, ss and copper certainly resist the "wettest" alcohol". A product made by Dow, Viton is also good for flexible lines. Then a change of injectors may be a good idea

... it's an interesting subject 
Denis

Paris, France

Had a race with a Lotus 7 yesterday near Versailles. They gave up at 140 kph : me in my comfy living room against them in their cockpit and wearing goggles is simply unfair ... I still gave them a thumbs up for the seven !

[OzBenzHead]

Well, folks, here's my 20 cents' worth on 10% ethanol-in-petrol blend:

About four years ago I had the misfortune to have to fill up my W108 280SE at a Newman servo in Brisbane; I had been on reserve for two days (just local runs), and there wasn't another servo within coo-ee.

Within the hour, Karl Benz started to run like a kangaroo; he leapt forward in fits and starts rather than progressing in his usual smooth manner.  He was cranky to start, ran very rough when cold, and was far from smooth when warmed up.

Because money was tight at the time, I couldn't afford to ditch the bad juice, so I ran with it until the tank was nearly dry.  (I'm glad I only half filled it rather than wholly filled it with the kangaroo p*ss!).

It took an entire full tank of real petrol (and then a bit - probably about a full tank and a quarter) to get KB settled down and running right again.

Now maybe it's just that the Newman fuel was crap anyway, but the experience has put me off ethanol for life.  There is no way I'm risking the health of my old Benzes again with dodgy fuel.

A car would run better on the exhaled breath from parliament house in Canberra!

[Denis]

Hi ozbenzhead

I fully agree that running alcohol in a mechanically fuel injected car is looking for trouble. The stuff will just loosen up every bit of dirt, rust, etc.

I did this on a carburetted Audi once and I replaced two fuel filters in two weeks before the carburettor would not accumulate anything. that was a 30% blend and worked fine.

I bet taht Karl benz ran very well with new fuel though...

Denis
Paris, France

[kastad]

Hi guys!

I believe that there's a misunderstanding going here. Ethanol does NOT attack rubber, but methanol does. Try put some gaskets or hoses in methanol or ethanol and see what happens. However ethanol sure cleans out the system -> clogging filters. :-(

A reason for poor running with ethanol is that the energy content in ethanol is less than in gasoline. This means that fuel pressure and (maybe) the ECU should be adjusted/changed to run properly on ethanol. A ten to twenty percent mixture however sounds interesting to me. No stress to change the fuel filter a couple of times in the beginning, but annoying if the injectors get blocked.

Anyone got more info about running on biofuels out there?

[Big_Richard]

Hi all,

In Australia the current blend involves only 10% ethanol and a list I found had >1986 MB as having compatible systems for this blend.  It does raise the question then about what could be pulled from a  W126 and fitted to our W116's.  I also have no idea what makes these systems compatible. 

remember, 1986 in Australia was when the sale of NEW vehicles designed to run on leaded fuel became illegal. I suspect theyre just taking the safe road and saying that if the cars are capable of running on unleaded fuel, ethanol will be fine.

[ponton]

I have run my carburetted 1977 MG on 10% etoh for virutally 5 years now, since it was about that time when it was a required component of gasoline courtesy of the feds (like the g-d corn farmers need another subsidy).  Although I dont drive it many miles a year, I have had no filter pluggin problems, my fuel tank is just as corroded as ever.  I know for a fact that the mileage is worse on the ethanol blend as I calculated it during the period when there was both available.  10% has been approved for all vehicles, anything above that requires changes to the fuel lines and the engine timing.  I have come to indirectly know one of the largest dealers of cars in the united states that says even the ethanol ready cars are having additional fuel delivery issues that never happened on straight gasoline and I am talking about cars that have used the same drive train configuration for 15 years that have been modified by the factory to cope with the fuel.  I personally think etoh is a waste of time and energy and simply lines the pockets of the manufacturers and producers of corn.  There is a slight net gain if you consider the capital inputs into ethanol production, but nobody considers the cost of the human input (that I have seen anyway) think about all of the energy those people consume to produce ethanol, when they could have been producing something else with the same energy input.  Meanwhile it drives the price of corn up, which is number one cereal crop in the world.  Anything made out of corn costs more, and anything that has a corn product increases in price (think dairy, beef, poultry, pork, high fructose corn syrup yada yada.  And in the united states, we are paying .50 dollar for every gallon produced in subsidy.  Corn is already the most subsidized agricultural product even without this additional subsidy, thus the extensive use in the food production industry.  Oh well, whats another false economy.

[thysonsacclaim]

I concur with ethanol, though the differences will depend on the ratio of ethanol (E15, E85, or straight). The corrosion isn't the real worry, but rather energy content, water, and air fuel ratios. I modified my first car, a 1986 Dodge Ramcharger (5.9 litre), to use ethanolized gas and straight ethanol for fun. We have a lot of racing here (I lived in Daytona Beach) so ethanol was cheap and easy to get (10 years ago). I also experimented with making it from potatoes, though it is difficult to get the proof high enough and I was 16 (coughcoughillegalcoughcough).

Ethanol is a slightly polar molecule, so it will attract water very well, which can be a concern. Contrast with typical hydrocarbons (ie alkanes like octane), which either are immiscible or only slightly soluble.

The problem is so much so that it becomes hard to separate water from ethanol. The two form an azeotrope; at about 96% mix they boil off at same temp. In order to get glacial ethanol (100%), you must employ methods such as zeolite molecular filters which allow water to pass through, but not ethanol.

That all costs a bunch of money so petrol companies don't do it. Besides that, the ethanol/gas mix will get water in it again by the time you get it in your car, then Condensation will add to that and so on. Water's no good and youll get decreased MPGs.

Our typical tanks at XOM hold 10k-15k gallons of gasoline. Prior to E15, typical ullage and water levels were low. Usually 2-3 inches of water. Now, even with modified tanks, we routinely get levels as high as 8 or 10 inches. It's quite common, though, but bad for consumers and for us because we need pump out tanks that exceed about 4.5-5 inches of water before it causes mayhem.

In your car, you can get away with using a water displacement product, such as HEET in the USA. Methanol, acetone, toluene and others often are put in gas additives and usually they are OK in **very small** quantities and they displace the gas/ethanol/water to give a more uniform mixture. Gasoline is attracted to ethanol, and ethanol is attracted to water, so it gets to be a jumbled mess if the ratios are too out of whack.

Re bio fuels, the easiest to get would be biodiesel if you have a diesel engine. There are more exotic things you can do, but all I know of cost more.

I don't know anything about K-Jet, but for D-Jet, I would assume you'd need to make several adjustments to the EFI system and may just be better off with a newer ECU system so you can get the maximum bang.

I've never run ethanol in an EFI car, but with carburettors it was not that big of a deal to switch. I made some adjustments to idle, put on a spare 4 barrel quadrajet carby and adjust points and needles. That's all I recall anyway, and it ran fine albeit slightly warmer.

Been a LONG time though, I'd like to find out more if anyone knows more (though I have no plans of ethanolizing my 450)



Ponton,

I personally think etoh is a waste of time and energy and simply lines the pockets of the manufacturers and producers of corn.

We posted at around the same time so I didn't see yours. I totally agree with you. Working for the petrol industry, I see some of the effects you mentioned. There are a lot of reasons why corn ethanol was not the way to go. I feel for farmers (some relatives are farmers), but you can only subsidize things so long before you need to find a new strategy.

[ponton]

I come from a similar perspective with family and friends as farmers, but there is supporting an industry that is necessary and is in need of assistance, but creating an unnecessary industry based wholly on the subsidies is ridiculous.  In fact the subsidies are supported moreso by large agrobusinesses such as cargill and monsanto so that they can controll the producers and wring as much money out of the process.  Anyway...

[kastad]

Interesting replies here. I may try a 10-15 % blend if possible on my D-jet. I'd have to find out octane levels though, but I doubt 10% will alter very much.

I'm anyways looking forward to bioethanol 2.0, that is ethanol based on wood, algae or other non-food organic components.
I have a newer diesel car as well and it's now available biodiesel based on fish waste in my area.

[thysonsacclaim]

Kastad,

Although it's a long way off, a neat thing I read about in a magazine we get at work was about bacteria that have been modified to create gasoline. This article is a bit old, but it describes the process. IIRC, BP is now experimenting with this process and seems to have a heads up on it:

http://www.technologyreview.com/Biztech/19128/