Convert gas engine to alcohol? : LUSENET : TimeBomb 2000 (Y2000) : One Thread

A bit late to ask this, but it might be of use to all of you with generators or other gasoline-powered devices. If RC and co. are even halfway correct about the coming oil crisis, it might be nice to have vehicles gens etc that can be powered by other sources of fuel. Supposedly, diesels can run on refined vegetable oil (this in fact is how Herr Diesel demonstrated his new engine, by running it on peanut oil). But for those of us with gas-powered things, is there a way to convert to running on naturally producible fuels such as alcohol or methane?

Jes' Thinkin'...

-- Little Pig (, December 28, 1999


Alcohol can damage various seals and "soft" parts of your engine and carb, unless they're designed with alcohol in mind. Propane and methane can power an engine, but you may ruin your valves unless they're designed for high-temperature service.

You can run them on volatiles baked off of wood, but you'll need to filter out moisture and crud. FEMA has a manual you can order that tells you how to do it with a couple of metal drums, some fittings, and some silver solder. Perhaps someone can repost the ordering information.

-- Ron Schwarz (, December 28, 1999.

I race methanol burning sprintcars so this is right up my can convert a gas engine to methanol by simply drilling out what ever jets the fuel mixture,allowing it more fuel.probly about 20% more fuel will be only drys out o-rings and gaskets over a long period of time,but you can buy a top end lube to mix with the methanol.

-- eric micael (, December 28, 1999.

Let me get this straight. You want to set up a still make some alcohol strong enough to power an engine, and then your going to use it to go somewhere instead of drinking it?

-- goldbug (, December 28, 1999.

eric: Thanks. Will this work for, say, a motorcycle engine? Ie is the higher compression a liability or a benefit? The engine I would be converting is a single-cylinder displacing about 650cc. Second, how does one go about producing fuel-grade methanol? Also, I would assume the methanol would degrade only those rubber parts it is in direct contact with, and not the oil seals on the engine. Is this correct? If so, can I get around this by using synthetic stuff, or coating it w/ something? Your input would be most appreciated.

Jes' Thinkin'...

-- Little Pig (, December 28, 1999.

Get a horse.

-- (homer@jethros.digs), December 28, 1999.

Our racecar engines are 16/1 compression and 410 cubic in.,we have also converted 5 hp honda go-kart engines both run will only dry out gaskets and o-rings that the fuel touches and only if you let it sit for a long time-more than a end lube solves the problem should be able to get a lube at a motorcycle shop.

-- eric micael (, December 28, 1999.

oh yeah-you can make methanol/ethanol just like moon shine...corn squeezins.if your in a racing area you can still get fuel for 1.50 a gallon in 55 gallon drums.

-- eric micael (, December 28, 1999.

Don't forget that alcohol-burning engines run much cooler than an similar gasoline-burning engine. You might have to figure out a way to regulate the temp, be it a smaller radiator or a flow restrictor in the engine coolant flow line.

A look at what the racers are using might be in order. Maybe the web site for somebody like Summit Racing or such.


-- Wildweasel (, December 28, 1999.

a 20% increase in methanol flow from gas is lean on the the methanol side.if your running it in a car 140 -230 degrees is a good operating temp.if you cant get enough temp simply block off the a motor cycle or anything air cooled you shouldnt have a problem.methanol runs best at 40 degrees outside temp,the engine may start hard below 32,but will run fine when you get the engine temp up

-- eric micael (, December 28, 1999.

Can you give us a name brand of a "top end lube"? Are you saying replace the regular engine oil with this special oil? You don't mean mix the lube with the fuel (like for a lawnmower or weedeater)? I am referring to an engine that runs on gas and has separate place to fill the oil...

By the way, can any one remind me of an easy way to "proof" the alcohol? I've got some good instructions on how to operate a still, but can't remember how to tell how pure the goods are.

By the way, did you know that the easiest way to distill moonshine is to put the jug in the deep freeze? The water freezes, and you can pour the alcohol off.


-- Berry Picker (, December 28, 1999.

Alcohol should not be wasted for gas. It is important to the human body. How else can I get chicks?

-- Dan Berard (, September 13, 2001.

I own and drag race my Alcohol Funny Car where I live. Just remember that when running an alcohol engine, you've got to choke it when it gets up to operating temp. This is because when the engine gets hot, the alcohol starts to vaporize and evaporate before entering the combustion chamber. So as the engine warms up, is needs to run more rich to compensate. Think of setting the carburetor opposite of what you would do when running regular gasoline. Also, be carefull not to backfire your engine when you are first starting it up, it could bend your carburetor float(s).

Good Luch

-- I GO FAST (, January 04, 2002.

I need to know all the steps to converting a gas engine. If you could help me or give me a web site to visit it would be greatly appreciated.

-- help (, January 22, 2002.

I ran a t/f funnybike in 92&93 was #2 IN U.S. I.D.B.A.& Prostar. The bike was a 1325 Kaw blow thru alcohol injected turbo. A gas engine requires almost twice as much alcohol as gas. Exhaust gas temps are much lower then gas.You can easily buy methanol (wood alc)from any go kart or race supply. Methonol contains oxygen ethynol has more but it is drinkable I couldn't get it. The easy way to stop seal deterioration is to run gas thru the engine before shut-down. There are additives also. Like nitro it will go past the rings and contaminate oil quickly. It will almost freeze an intake manifold.The exhaust fumes are toxic (formaldahide)try to stay clear. It is an excellent fuel especially for racing and mixes with nitro. Its all they use in Brazil and the US makes cars for their fuels every year. By the way the bike put out 750hp on our Superflow Dyno, I've got a 1400hp twin turbo sm blk. 71 Nova sittin in my driveway love those turbo's....good luck..Turbo Stu

-- Stuart Farrar (, May 07, 2002.

I've got a 5hp Briggs & Stratton motor(carburated) on a go kart. I clocked it at about 23 mph. I just want more power and speed out of it, but i don't want to spend alot. Is converting it to alcohol the simplest and cheapest way to add power?

-- Kart'n Kyle (, September 27, 2002.

I have 1976 Cadillac hearse w/ a 510 c/in engine. Has anyone converted a similar engine to ethanol? Anyone know of any engineering classes working on similar projects?

-- peter (, October 02, 2002.

I am currently converting my Honda Cr 250 motocross bike to ethanol. Only minor tuning remains . I hope I can help lay down some answers for anyone who wants run ethanol. First of all I built an insert to raise the compression to 15 to 1. The chamber has maximum quench - .035'". No timing changes were required to the engine due to this.The fuel is 99% ethanol with 1% gasoline denaturing agent mixed 45 to 1 with Maxima 927 racing castor as the lubricant. The carburetor is a Mikuni TMX with a custom made needle and jets .The main jet on gasoline was a #410( .068" ID) now it''s been opened to .093"( 90% larger hole size in surface area) This project has been under way for several months with the fuel left in the carb during this time. No corrosion or seal damage is apparent.The US Motors website has a chart showing the effects of different chemicals on electric motor housings with ethanol not showing a corrosive effect under 150 F. Spark plug selection has not been finalized but it looks like it will be 2 or 3 numbers hottter on NGK's scale. Initially detonation from running lean jets blew the orings a few times out of the cyl.head, but tuning is eliminating this . Removal of the head revealed no damage to other than the orings. The engine runs perfectly clean with no carbon or deposits what so ever. Compared to gasoline the bike has picked up enough torque from low to mid range to feel like an engine twice its size and on top it pulls hard enough that I'm shifting constantly to keep it from winding out. I'm sold. I'd be glad to answer anyone with their questions on ethanol

-- hang on (, November 03, 2002.

Could I convert my rc racecar to alcohol? It is a diesel motor after all. Well its just an idea.

-- BIG AL (, January 28, 2003.

I was wondering could you convert a 25cc aircooled weed wacker engine tto alcohol its in a 50 inch boat.

-- Ryan Kenney (, January 30, 2003.

Alcohol, Propane, Methynol, Natural Gas? these may be better than Gasoline, but they're still aren't clean fuels. the only logical fuel to convert to is Hydrogen. you get longer engine life, zero emissions, no more oil changes(simply replace the oil filter and top off at regular intervals),starts in the coldest weather(the colder it is the better it runs). and anything that uses a petroleum based fuel can be converted to hydrogen.

-- Todd Klatt (, April 21, 2003.

look around on the internet they mak books on your spacific engine for alcohol or what ever thats what i did bought a ten hourse techumsa motor bored it out forty over changed cam conecting rod piston to light weiht and very durable its running acohol plus nos it was tested for thirtynine horse and i can reach speeds easy of one hundred hundred ten for a bout cost of 500.00 thanks and keepem ruber side down

-- bob jefferson (, May 17, 2003.

Hydrogen may be clean burning, but as of yet, the process of getting it is worse on the enviornment than using gasoline. Unless you use nuculer energey to use electrolosys witch is about .001% efficient way of getting hydrogen. better off using the electricity in electric motors. how does an ethonal burning engine compare with a gasolines emisions?

-- paul dice (, August 07, 2003.

well i dont have an answer but i do have a "?".if i was to convert a 4 h.p briggs &stratton engine into burning alcohol how would i do it.what kind of seals would i have to use.thanks chris

-- chris sap (, November 25, 2003.

i have a 1986 yamaha big wheel 200 4-stroke. i want to run acohol in it and you can. my dads friend had to 110 three wheelers as a kid and he bored them out to 190 and ran acohol in one and av gas in the other. you just have to have a cam specially made for the acohol and you can do it.

-- Prestin Vaughan (, November 30, 2003.

About hydrogen... I think the engine oil would still have to be changed. The engine is still a hot environment (contributing to thermal breakdown) and the air participating in the combustion process is still dirty (even though your air filter helps out). Oil changes would be few and far between though since the oil doesn't get gasoline contamination at all. Sorry to get off track, by the way...

-- Joe Plumley (, December 01, 2003.

I have a echo weed eater and im curently running it on 20% modeling fuel which is 20% nitro 5% caster oil 15% synthetic and 60%methanol its going to be in a 60 inch rc boat the motor has had flames comeing out the exhaust at many times while tunin

-- thomas william (, December 21, 2003.

Hey guys, I'm thirteen and I'm doing a science fair project.. can someone from here or anyone e-mail me at and tell me how burning gas makes a car run?! Please!? Thanks, bye.

-- Audrey (, January 13, 2004.

wow your thirteen and you dont kno how and engine works???? go to and look there...... other then that i want to do the same as alll you toehrs convert tot alchoahl becauase more power! and my go cart is f-in slow and i wanna go faster so pelase e mail me with instructions..... and im assuming the stock carburator can be cahnged to do this??

-- alex r koji (, March 11, 2004.

Here's a link. Not very performance related. But Should aid in the convertion.

-- Shaun (, March 17, 2004.

I am looking at converting a motorcycle engine to alcohol and need some info on what heat range spark plug to start with. Any info is much appreciated.


-- ryan akkerman (, March 23, 2004.

Here is a great documentary on the engineering challenges, both materials & performance wise, that will have to be overcome/changed in the automotive industry infrastructure before ethanol based vehicles are a reality.

-- Bill D (, April 19, 2004.

i am fithteen and i have a go kart with and 8hp techumsa in it. i am wounderin if anyone knows if there are any performance parts for the motor. If soo what kind and where can i get them and what is the website thank you

-- david (, April 25, 2004. think that we could get some tubing that runs from the tail pipe into the car....that was we wouldent be wasting boose, and we just might have found the new drug of 2004

-- Dr. Crack'a (, May 07, 2004.

Hi- I'm just beginning to learn about ethanol conversions and I was wondering if there is anyone out there who knows of useful references- websites, organizations and so on- or if anyone would like to share their knowledge over email... just thought I'd ask- thanks a lot- Sara

-- Sara (, May 31, 2004.

Hi guys I'm an Italian man. Here in Italy a lot of people converted their gasoline cars into propane/methane cars. There are specialized sellers. Now technology has been well developed and one can loose just 10% or less in engine power. look here and we have other factories like this.

-- Andrea Frigo (, July 19, 2004.

It is interesting how long this thread has been kept alive. I am noticing a trend towards poopooing hydrogen as a non-viable alternative because the "present means for production are too polluting." Well, no, that isn't entirely true. Steam reformation and electrolysis through hydrocarbon powered generators will pollute, yes, but you don't have to go that route. A solar generator (and I'm not talking about those bloody solar panels that just won't go away) could produce all the hydrogen we'd need with absolutely zero emissions. Somebody just needs to get off their lazy arse and do it.

I also noticed several people asking for sources of methanol. The only way that I know of as far as homebrew is through destructive distillation of wood. Basically, you heat wood in the absence of O2 and condense the resulting gas, and then from there you distill the cooled liquid, which gives you methanol. Google it, there's heaps of info on the web about it.

I'm pretty furious at the moment about gas prices; I made the mistake of hoping prices would hold off for another day, and then they jumped about $.15/gl. Makes me seriously consider purchasing a bike off of eBay and converting it. I'm wondering how well it would work to heat the alcohol to its boiling point prior to injecting it into the cylinder- wouldn't it burn much more thoroughly? Just a thought that ocurred to me today when a co-worker was explaining to me the fun one can have with a supposedly "empty" gasoline tank. Cheers mates, and stick it to the oil companies :0D

-- Andrew (, August 05, 2004.

My old man has a home brew setup, and he says he can produce 180 proof alky without formaldahyde through carbon distilling. If anybody is interested, you'll need a pipe 1.5m long, about 3/4 inch wide, with a piece of filter paper on the bottom, and a good sized funnel. Fill the pipe full of distiller's carbon (it will need to be moist, run it through with water and wait for the water to drain out) and run the alcohol through. What comes out is pure, if not very close to it.

You may need some clamps to ensure that leakages are kept to a minimum. A good way to do it is to get another piece of pipe one size smaller, stick it in the top end of the larger pipe and use a clamp (the round sort) to tighten them around the bottom of the funnel. This will result in the thing being bloody air-tight, so expect it to bubble like crazy when you put the carbon in.

Now for those in the know, 180 proof alcohol loses its strength after awhile when it contacts air, so a good idea would be to pipe the resultant alcohol into an airtight container that can hold it, then pipe it straight into the still. We have a container we keep alcohol in that has a tap on it and a pipe coming out the lid, so when we need the stuff to flow, we just turn the tap on.

Hope this is a help... just note that this practice may not be legal in certain regions... apparently a home built still is illegal in Australia.

-- Steady (, October 07, 2004.

Howdy folks... anyone know of a resource for converting motorcycles to alternative fuels? Specifically ethanol or propane (LPG). Any help is greatly appreciated. Please respond to my eMail address. THX

-- Max Headroom (, October 27, 2004.

Check out

Oh yeah and you can convert a Diesel engine to Biodiesel (I think grease)

-- Vinay Gidwani (, November 21, 2004.

come on how come no one has provided a straight answer on how to convert a gasoline engine into alcohol? i want to know too.

-- jewish man (, December 03, 2004.

Well when it comes to Alcohol.. talk to a brazilian.

That in fact happen to be me.

Basically you should be increasing your mixture to be 50%+ richer than petrol. You will also need to be running 180 proof or richer. (198-200 proof if you plan to mix it back and forth between petrol) You may need a electric fuel pump if you have a mechanical one

Now it all depends on your vehicle but the best way to heat the alcohol is to wrap some thin metal tubbing around the exhaust manifold inbetween the fuel filter and the injectors/carby

If you want to increase the performance increase the compression and advance the timing (alcohol's 'octane' rating is higher than premium petrol) also many spark plugs have two types for each model vehicle... pick the hotter ones!

Also if you have a fuel injected car usually you can get a 10c resistor that tricks the computer into thinking it is running lean and it pumps more fuel.

Personally if you going to do it the conversion look into getting hold of 200 proof alcohol/ethanol/methanol and mix it with a little high octane premium petrol (10L of alcohol to 1L Premium) in fact pick a brand like Vortex in Australia that has a lot of additives because that what you want it for not the octane (in addition add a bottle of nulon premium octane booster every second full tank )

Also, Alcohol will make your engine run cooler and clean all the gunk build up in your engine... so don't be alarmed if you've done all of the above and it splatters and shudders. Just rev it softly up to around 2500rpm for a few minutes... older and high milage cars may need to 'settle in' over 2-3 tank fulls

Lastly if you carry a little metal army water bottle in the boot with a little premium petrol on those cold days when the alcohol just wont start spill a cap full of petrol into the carburator and always let your engine heat up for at least 3 minutes if you don't have a manual choke (time it with a watch)

-- Seth Santos (, December 14, 2004.


Hi Kenny, I was just reading your question regarding a 25cc engine to alcohol. Did anyone ever answer you? I am interested also in experimenting with a 25cc weed wacker motor in an experimental 100 lb. aerodymanic 15 mph distance car. My daughter brought the "skeleton" of this idea home from school and I came up with the 25 cc idea, a super light- weight skin, the basic layout, etc. I have been fasinated by this project ever since. Furthermore, currently, as far as I know, all 25cc motors still have carburators. Do you know of any ultra-small injectors in this range? Please let me know how you are doing. Maybe we could share some information. Thanks, Steve Biggs Crawfordsville, IN 47933 ============================

-- Stephen L. Biggs (, January 07, 2005.

You may need a alcohol carb to run off alcohol. If you are converting a 5hp B-S, then just buy a alcohol carb (the're not hard to find) and expect to gain about 1hp. By the way, did you know that you can run a diesel off of hemp oil (A.K.A Marijuana oil)? You can probobly guess what comes out as exhaust, whitch may be a good or bad thing, depending on your preferences. And you can also run a gasoline engine off of kerosene. Trust me, I've done it!

-- speed racer (f@f.fff), February 01, 2005.

Here in the Midwest, we can buy E-85 (85% ethanol, 15% gasoline) at some gas stations. I've been running my '92 Suzuki GS500 motorcycle on it for almost two years. The "conversion" wasn't so much of a conversion, as just plain-old tuning.

When I first put E-85 in the tank, I tried starting it, to see if it would run. It was waaay too lean. For fun, I put a bathtub strainer over the air filter intake, and put different sized disks in the strainer basket, to choke-off the air intake (make it richer). It was still too lean. Finally, I stuck a Dixie cup in the air intake, completely blocking the air intake (as far as I could see). Finally, it would idle (although not smoothly).

So then, I embarked on tuning the engine to run richer (without the Dixie cup). I enlarged both the idle jet (to 143% of stock jet diameter) and main jets (to 128% of stock jet diameter). After tuning the pilot air/fuel mix, I've been running in this configuration successfully. My best guess is that in spring/summer/fall, I'm getting about 75% the MPG as I did with gasoline.

Other changes I made are: use synthetic oil (Mobil-1), since dino oil does not mix at all with ethanol; went one plug hotter on NGK's scale; advanced timing from 5 degrees BTDC to 12 degrees BTDC. If I were serious, I'd use domed pistons to increase compression ($300 + labor), and change the sprockets to take advantage of the added torque. I suspect that I could get 90% of the MPG.

But for now, I'm happy to burn E-85 with minimal changes to the carburetor. Most people should do fine with just changing the carburetor jets and maybe switching oil. Burning pure ethanol would be similar, but the increases in jet size would be a little bit more extreme.

Note that motorcycles are good for this, because there is a short manifold from the carburetor to the engine. Cars have more complex intake manifolds, and may benefit more from a manifold heater.

I have a few notes about the conversion and E-85 at http://E85.SpecialGreen.Com . Feel free to drop me a note there.

-- Special Green (, February 20, 2005.

so- price difference between gas and alcohol, purchased at a store? Is alcohol better on the environment than gas? Efficiency (both cost and function) and emission are both really important to me. I'm currently searching for a class B van that I can use as both a home and auto. Diesel engines are too expensive in this model, so it looks like I've gotta go with gas. Or, can one switch a gas engine for a diesel engine? Ideas? Thanks.

-- blair pendleton (, February 23, 2005.

Look, i'm the same as the others,.........well i'm not the same cause my parets tell me i'm pretty special. Well anyway, i'm 14 i just got rebuilding an engine in my dad's truck, i have rebuilt many go-cart enginges, however i am not experienced with converting them to alchol. Could any one post some helpful replies, or email me

---IT's been real, It's been fun, but it hasn't been real fun!

-- --Gear Head (, February 24, 2005.

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