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flex fuel
8

flex fuel

RE: flex fuel

(OP)
what I would like to know is why can it be done in the states?
what are the modifications required for flex fuel vehicle.
my understanding it's all about the corrosive nature of alcohol.

Mfgenggear

RE: flex fuel

It is done in the USA and I think almost all developed countries.

The fuel systems needed upgrading to avoid corrosion of metals and chemical attack of polymers used in the system.

As the different fuels require different a:f the EMS requires a source of data to correct a:f for fuel type. I am not sure what they use for a sensor or what happens if the sensor fails.

Regards
Pat
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RE: flex fuel

(OP)
I am observing more Hybrids than flex fuel cars. and no areas to fill with E20 or above. it seems it just faded out.
more a combination of electric & gas motor, or full electric.
The electric cars are unbelievably expensive.

I live in southern california and it seems that there is BS happening with the gas prices here.
The fuel injection with alcohol & water was an interesting subject also.
it would be nice to be weaned off gasoline.(petrol).

Mfgenggear

RE: flex fuel

(OP)
it seems the nearest flex fuel is 15 miles, plus the an additional 15 miles from where i live so 30 miles.

mfgenggear

RE: flex fuel

(OP)
there appears to be approx. 18 gas stations in california with alcohol.
what gives.

Mfgenggear

RE: flex fuel

E85 became economically competitive only with a government subsidy to Archer Daniels Midland amounting to $6B/year. The subsidy has run out.

No worries; the corn lobby continues to suck on the big teat in DC.

Mike Halloran
Pembroke Pines, FL, USA

RE: flex fuel

FWIW, I've never seen E85 priced competitively with pump gasoline on a $/BTU basis. To be competitive energy-cost-wise, E85 needs to be about 70% of the price of gasoline by volume. Regular gasoline price in Michigan this week is about $3.50/US gal, minimum. A competitive price for E85 would be about $2.45/gal. Didn't get a chance to check E85 price lately but I'll bet it's close to $3/gal.

"Schiefgehen will, was schiefgehen kann" - das Murphygesetz

RE: flex fuel

I think with a compression ratio to take full advantage of 85% ethanol, beter fuel economy than the energy content suggests could result, but to keep an engine configured to run acceptably on a wide variety of fuels costs economy on every fuel vs a dedicated design. Sure tune adjustments can compensate, but will still not match the results from a dedicated fuel with the engine optimised to that in configuration and tune.

Regards
Pat
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RE: flex fuel

Pat, I fully agree. Since almost every vehicle these days, flex-fuel included, is configured to run on regular gasoline, CR is definitely not optimised for E85. The only tangible improvement you might expect when running E85 in a factory stock vehicle is a little bit more knock-limited peak power, assuming that the engine controller is configured to run at the knock limit at WOT.

"Schiefgehen will, was schiefgehen kann" - das Murphygesetz

RE: flex fuel

Are some of these engines arranged to automatically analyse the ethanol/petrol proportions of the fuel heading for the engine and adjust the amount of fuel injection to suit?

RE: flex fuel

I believe the strategy is something along the lines of, when the vehicle is restarted and the fuel level has increased significantly, any dramatic shift in air/fuel ratio that is detected by exhaust oxygen sensors is attributed to a change in the proportion of ethanol in the fuel, and special learning tables are set up to adjust the open loop fueling, so that the closed loop correction tends toward zero.

"Schiefgehen will, was schiefgehen kann" - das Murphygesetz

RE: flex fuel

There are sensors in the fuel line that tell the ECU the percentage of alcohol in the fuel so it can make fueling adjustments. I don't know what principal they are using to sense it.

I've seen a few hot rodders build E85 specific vehicles that take advantage of the high octane level of the fuel. These are mostly trailer queens as you can not find a reliable E85 source in most driving areas.

Corn based E85 has never made sense to anyone but the pointy haired bureaucrats in Washington. At least they have taken the tax off imported Brazilian ethanol (I believe). Maybe some day when they perfect cellulosic (sp?) or other better non-food based ethanol production it will become something other than a tax payer boondoggle.

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The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows.

RE: flex fuel

(OP)
The gasoline price here in southern cal is at average of $5.65 imperial gallon.
I would gladly pay the $3.00 for a gallon of E85 if I had a flex vehicle.
plus less pollution right?

Mfgenggear

RE: flex fuel

Where can you buy an imperial gallon in the US?

E85 is over $3 for a US gallon here and regular is only $3.40.

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The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows.

RE: flex fuel

(OP)
dgallup
US gallon is not same ? oops
Bad on me.

I wish it was $3.40 a gallon here.
I would be saving $2.25 a gallon.

Mfgenggear

RE: flex fuel

(OP)
"I've seen a few hot rodders build E85 specific vehicles that take advantage of the high octane level of the fuel."


If I wanted to convert a pre 1967 style chevy vehicle (chevy 350 carbureted) engine to run on alcohol, what would be needed.
besides stainless steel lines. what type of hose connections, altered carburetor.
what if I made a still(methanol?) for personal use. where can I get a design to build it.

Mfgenggear

RE: flex fuel

Quote (dgallup)

There are sensors in the fuel line that tell the ECU the percentage of alcohol in the fuel so it can make fueling adjustments. I don't know what principal they are using to sense it.
Sounds plausible but I haven't come across one. Can you cite a late model application using such a sensor? I'd like to investigate.

Quote (Mfgenggear)

I would gladly pay the $3.00 for a gallon of E85 if I had a flex vehicle.
plus less pollution right?
IF the calibration for E85 is as well optimized as the calibration for petrol, then yes, HC, CO and NOx should all be lower. And then, if CO2 is classified as pollution (which is debated), then cradle to grave CO2 "pollution" might be reduced also, but that is a hotly debated question, due to the existing methods of ethanol fuel production.

"Schiefgehen will, was schiefgehen kann" - das Murphygesetz

RE: flex fuel

Pat - Corn based ethanol production comes from the fermentation of the sugars, not the cellulose, just like Brazil's sugarcane based ethanol. The vast majority of the plant matter (cellulose) is unused. If fact it's sold as live stock feed indicating just how much of the energy content is unused in ethanol production. There are lots of companies (& federal $$$$) trying to tap all the rest of the energy with what they call "cellulostic" fermentation, don't ask me to explain, I'm no chemist. The goal is to use all the cellulose in cheaper sources like switch grass.

Mfgenggear - It's not really difficult to make a system E85 compatible, it's not very aggressive. The people who have had the most problems with ethanol are the boaters because of things like fiberglass tanks dissolving and cheap fuel lines, pumps, etc. Everything sold automotive in the last decade+ has been ethanol compatible at pretty much any concentration.

Methanol is a totally different story and you will be hard pressed to find compatible elastomers, fuel lines, pumps, etc. Only the hard core racing community uses it and not so much there anymore since even they have gone "green" and switched to ethanol in many series.

----------------------------------------

The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows.

RE: flex fuel

E 85 is ethanol not methanol. They have similarities but they are quite different in some ways. Ethanol is the product of fermentation of starchy or sugary vegetable.

E85 is ethanol based and while moderately corrosive, it is nowhere near as corrosive as methanol and SS lines are not really required.

You do need to ensure all hoses are ethanol compatible. Anything rated for methanol will be more than good enough. Anything rated for strong spirits like Vodka will also be good enough.

I would tend toward brass fittings and copper or SS or coated steel or even nylon pipe/hose.

For ethanol, you need to allow for about a55 to 60% increase in fuel flow everywhere in the system including the tank breather vent.

The carby will need bigger "alcohol" SS needle and seat. It's generally easier to use dual inlet carbies if they are Holley type.

You need to increase main jet CSA by about 55% but also idle and intermediate fuel circuits. You need to ensure the emulsion tube wells will also handle the extra fuel flow. Sometimes it's easier to just use a greater number of carbies with smaller chokes for the same airflow but more potential fuel flow. You still have to tune the jets though.

An extra booster electric fuel pump and extra fuel pressure can help get the flow up through std size pipe and fittings, but once in the float chamber of course this does not help.

Some manufactures off methanol carbies. They would flow to much fuel, but could be easily jetted back and maybe the idle could be fixed with the adjustment screws. The intermediate circuits might still be rich though.

If you go methanol, the same deal only more so. You would need all fuel flow areas to be slightly over double.

Another issue is cold weather starting. Ethanol and especially methanol don't like to start in a cold engine. High compression helps here as does a strong ignition system, but most methanol fuel race cars use a spray bottle with normal petrol to start it up. You could possibly rig up a seperate petrol squirter powered by a small electric fuel pump and push button activated as a starting primer. Just don't touch the throttle until it fires.

Of course the limited range and availability of fuel when away from home should be obvious.

Regards
Pat
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RE: flex fuel

(OP)
dgallup

I am confused, I meant ethanol still. & ethanol fuel , senior moment kicking in.
LOL
I hate when that happens.
Items I would have to replace ?
Tank
fuel lines

so existing Holly or edelbrock intake & carbs.

mfgenggear

RE: flex fuel

(OP)
OK thanks pat.

ignore my last post

Mfgenggear

RE: flex fuel

(OP)
I did read, for previous versions of flex cars, a separate start up tank with gas was used.
how could I jerry rig this?

Mfgenggear

RE: flex fuel

Intake will be fine.

Carby will need mods.

A methanol carby will have the corrosion resistance well and truly covered, but it's easier to increase the fuel flow drilled restrictions/jets and slots than to decrease them. Of course the screw in ones can be easily replaced with suitable size.

I think you can buy methanol conversion kit for Holleys with all materials upgraded where required. Things often overlooked are needle and seat and accelerator pump diaphragms.

You also picked up on the tank. That is an often overlooked item. Even serious racers use aluminium tanks which after only a few years start to corrode and produce a white fine powder that racers call white rust. Once again, ethanol is not as bad as methanol. There is no problem until the anodised layer is eaten away which takes some time, especially if hard anodised, but once that's gone, the corrosion really accelerates.

Regards
Pat
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RE: flex fuel

BTW, the "white rust" from aluminum is in the form of a gel when it is immersed in the fuel. This gel plays hell with fuel filters. The recommended coating for aluminum parts wetted with methanol is electroless nickel plate. I expect this would be fine with ethanol as well.

"Schiefgehen will, was schiefgehen kann" - das Murphygesetz

RE: flex fuel

Electroless nickel does very well in ethanol.

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The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows.

RE: flex fuel

hemi--the presence of "white rust" indicates corrosion, most likely of an aqueous nature. In that case, you do not want an electroless nickel (ElNi) coating on the aluminum. If a pinhole developes in the ElNi, you will be in a galvanic corrosion situation with a large cathode surface area (the coating) and a small anode area (the aluminum exposed by the coating breach).
This will lead to pitting and eventually perforation of the aluminum.

RE: flex fuel

Agreed, the plating is a band-aid for parts that are originally aluminum. It will be down to the plating quality whether there are pinhole issues or not. Preferred material is of course stainless steel in suitable grades.
At any rate, during the M85 era in California, there were terrible issues with the drop tubes going down to the supply tanks at the fuel stations, since they were bare aluminum. The gel resulting from the corrosion was pumped into vehicle tanks, and clogged their fuel filters. A corrective action that was employed at the time was to replace the drop tubes with nickel plated ones. Since the integrity of the tubes was not the issue, only the contamination of the fuel, I expect that this corrective action would prove to be effective. The M85 era came to a fairly sudden end, before the life expectancy of the plating (in methanol exposure) was really tested.

"Schiefgehen will, was schiefgehen kann" - das Murphygesetz

RE: flex fuel

hemi,

You are correct about the function of using the fuel level sensor to watch for a refill event, and then after that there is a learning period where the ECM attempts to "learn" the new ratio of E85:gasoline based on lambda sensor/fuel trim feedback, allowing it to adjust the fueling to mix. This was done for several years on recent GMs, and I think Fords too.

However, the earlier flex fuel vehicles here in the US, and I believe many in other countries, use an ethanol sensor. Also, the manufacturers here in the US are switching back to using a sensor. The other strategy was to save them a few bucks, but it was problematic, complicated to program, slow to respond, etc. A failed fuel sender would then cause issues with the car relearning the fuel ratio... Too many issues.

Of course when I go to look for the info, someone has walked off with it. So I can't give you an exact part number or application for the newer vehicles.

But here is a place that makes a lower cost copy of the factory sensors:

http://www.pointaengineering.com/

And if you search for "flex fuel sensor" or "fuel composition sensor" with respect to GM or Ford you will find plenty of them around. I think Megasquirt even has details on how to interface to them.

RE: flex fuel


Ignore the link. They are a sensor "replicator", that are merely putting out the right signal, as if its on gasoline the whole time. If I remember right, that is something around a 50hZ square wave. Kinda pricey for a 555 timer circuit.

But there are plenty of places to get the sensor. Since the link above was worthless, here is the MS link that shows how the sensor functions, where to get it, etc:

http://www.megamanual.com/flexfuel.htm

RE: flex fuel

Mfgenggear
swall (Materials
hemi--the presence of "white rust" indicates corrosion, most likely of an aqueous nature.

That imfamous white rust has driven me nuts with outboard motors on boats for the last couple of years.
so I am now switching to a different flex fuel, Propane. It does not get the MPG that gasoline does.
On the other hand I am paying $2.19 per gallon for Propane in San Diego. You cannot get more Southern california than this
It also does not attract the water into the fuel that helps form the white rust.
B.E.

The good engineer does not need to memorize every formula; he just needs to know where he can find them when he needs them. Old professor

RE: flex fuel

On the conversion systems we make(automotive based) generally propane seems to have the game MPG as gasoline. CNG is down a little from either. How much % are you losing in the propane switch, and how are you metering it?

How big of a tank do you have for your propane powered boat? Seems like you could wind up adding a lot of weight with that.

RE: flex fuel

(OP)
On the other hand I am paying $2.19 per gallon for Propane in San Diego.

berkshire

what the ? I also live in San Diego, I don't get propane that cheap. LOl

Mfgenggear

RE: flex fuel

mfgenggear,
You are right, I get the 2.19 price in El Cajon.
to get the lower price you have to go to the welding gas supply houses I.E. Westair.
Stay away from gasoline stations and especially Blue Rhino. they will get you for over $5 per gallon.

bradrs
I am currently using a dedicated Propane motor made by Lehr. It is a 5hp motor is burning less than 3/8 gallon per hour running solo at 75% throttle, and 5/8 gallon per hour running flat out pulling a string of boats. This appears to relate quite favorably to the consumption rates of the gasoline motors. I am chief of maintenance of a sailing club and purchased this motor for evaluation. I have five other motors in the 4 to 6 hp range. In the month of May of this year I spent $1600 on carb and fuel system parts, mostly due to water contamination in fuel
I am now talking with a conversion company about switching the other gasoline outboard motors to Propane.
In answer to your question on tank size, I am using one gallon tanks, which give an average of 3 1/2 hours run time. After I bought the one gallon tanks the maker of the motor told me that this engine will run equally well on a liquid propane supply, and suggested a 5 gallon tank laid on its side.
B.E.

The good engineer does not need to memorize every formula; he just needs to know where he can find them when he needs them. Old professor

RE: flex fuel

In my experience an engine fully configured to optimise running on propane does a LOT better on propane than one configured for std pump petrol that has only had fuel system mods as necessary to run on propane. For one, propane can tolerate about two full points of compression higher.

Regards
Pat
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RE: flex fuel

(OP)
berksire & pat

Thanks for the responses.
what are the requirements to convert to propane ,
I will also google this but I prefer to get first hand from the experts here.
how about a larger outboard motor. let say 70 HP, 4 stroke








Mfgenggear
if it can be built it can be calculated.
if it can be calculated it can be built.

RE: flex fuel

berkshire, I may be preaching to the choir, but do be very careful with propane and water vessels. They can be an explosive combination, literally. Any leaked propane will pool at the bottom of the hull, forming a potentially flammable mixture with air. Assuming the dedicated propane motor you're using is intended for marine use, I'm sure all the proper precautions are prescribed by the manufacturer.

"Schiefgehen will, was schiefgehen kann" - das Murphygesetz

RE: flex fuel

In the UK a few years back we had a small E85 "moment" with flex fuel cars available from Ford (Focus), Volvo and Saab.

These were all equipped with fuel sensors ( I also have no idea how they work) to detect ethanol content and adapt to make the drive experience seamless. Saab made a bit more of it by upping the boost while running E85 quite a bit so that car at least had quite a bit more power on E85.

Trouble was that E85 availability was patchy (though one supermarket did make it available at all their stations) and it was priced the same as ordinary 95 octane petrol in spite of a government subsidy. There were some tax incentives available and a 20% rebate on the fuel but as fuel use was at least 30% more this wasn't a particularly great incentive! So not many cars sold. Not much E85 sold. Now they just dose ethanol into all our fuel at 5%,possibly rising to 10% in the future as is already the case in much of Europe. I think that in theory there are still flex fuel cars available new but I'm not sure where they find the fuel as since the subsidy lapsed in 2010 it seems to be more or less unavailable.

As an aside, while it was available, I messed up and unintentionally filled my late 60's Triumph with E85. Fitted with home-brewed electronic injection, my error showed up immediately (no float bowls!) and the car ran very badly. However, it was able to drag itself 10 miles home to a laptop. After upping the fueling by 30% across the board it did actually run reasonably well, but with a long trip planned for the next day I chickened out and drained the tank. My elderly Honda mower drank the rejected fuel over the next two summers and actually ran perfectly well on it apart from being very hard to start from cold.

I've not had any problems running the electronically injected Triumph on E5 or even E10, but on a continental trip last year, several other 60s Triumphs in our party had major issues after filling up with E10. All were carb equipped cars and mostly related to really bad vapourisation, with a couple of fuel pump failures thrown in. A couple of cars with Lucas mechanical injection also appeared unaffected.

Nick

RE: flex fuel

Hemi,
Yes propane is heavier than air and will collect in bilges, so will vaporised Gasoline, as far as I can see neither is any worse than the other and both require the same steps to remove them.
B.E.

The good engineer does not need to memorize every formula; he just needs to know where he can find them when he needs them. Old professor

RE: flex fuel

Ummm

At typically 150psi tank pressure and a small molecule that diffuses through rubbers that are very impervious to petrol, a very small leak can deposite a hell of a lot more vapour a hell of a lot quicker than can petrol.

Do not underestimate the extra precautions required. I would only have a tank that is in its own sealed compartment except for a vent overboard.

I would instal vapour sniffers.

Regards
Pat
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RE: flex fuel

Pat,
The fuel tanks are situated in the open cockpit of the boat under the seats. There is a bilge blower.
B.E.

The good engineer does not need to memorize every formula; he just needs to know where he can find them when he needs them. Old professor

RE: flex fuel

(OP)
thats why I prefer outboards, less chance or zero chance of vapor build up & a then an explosion.
I have own a few boats with outboards.

inboard outboard only have issues when the blower fails.

Mfgenggear
if it can be built it can be calculated.
if it can be calculated it can be built.

RE: flex fuel

(OP)
lol, yes but as longs as you don't light that stogie while while out sea.
any leak is dangerous,so it is important to do an inspection, prior to launching.
in case of inboard outboard drive, make sure that blower is on before starting that engine.

since the outboard may or may not have a built in gas tank. & the out board has no enclosed areas where gas vapor may pool.



Mfgenggear
if it can be built it can be calculated.
if it can be calculated it can be built.

RE: flex fuel

I have yet to see a medium to large outboard with a built in tank.

I have yet to see an outboard of any size with an inbuilt LPG tank.

Agreed an outboard reduces the risk especially in small open boats, especially as sparks from the starter are outboard, but I sure would not encourage complacency on a larger enclosed boat.

I have been involved enough to extinguish one inboard boat petrol fire. Close enough to get a lot of singed hair. Lucky I was already reaching for the extinguisher as soon as I saw the drivers hand move toward the starter button when I knew fuel in the bilge.

A similar LPG leak would have been a major explosion, not an extinguishable fire.

Regards
Pat
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RE: flex fuel

(OP)
agree, the danger is in vapor not pooling gas, right, if there is any vapor lpg or gasoline it will explode.
My ex brother in law & myself threw some gasoline mixed with racing oil into a 50 gallon drum to burn some trash & weeds.
"this is when I was 14 so I claim naive at the time". now I never use gasoline to light fires. OK
I let sit too long that's is why it exploded.
I seen an old mechanic put his cigarette out in a can of gas because I was complaining it would explode.
guess what it put the cigarette out without incident " don't try that at home folks"


Mfgenggear
if it can be built it can be calculated.
if it can be calculated it can be built.

RE: flex fuel

(OP)
Pat

I have seen large boats with built in tank with outboards.
lots of them, here in san diego there is boats that go 50 or more miles out for TUNA.

being there done that.

Mfgenggear
if it can be built it can be calculated.
if it can be calculated it can be built.

RE: flex fuel

(OP)
I wanted to thank you all for your replies
thank you pat for tips on the carbs

I look forward with great safety in mind to explore the flex fuel & the making of ethanol.
This will be a multipurpose piece of equipment.
distilling water should it be necessary "emergency"
making emergency fuel ie "cooking, generator, vehicle"
emergency antiseptic, "alcohol"
maybe for the spirit " happy drink"

Thanks again all

Mfgenggear
if it can be built it can be calculated.
if it can be calculated it can be built.

RE: flex fuel

(OP)
Pat

what I mean by built in tank is in the boat itself, & not built into outboard motor. LOL.
sorry, have to explain myself better.

Mfgenggear
if it can be built it can be calculated.
if it can be calculated it can be built.

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