Easy BEGINNERS Guide to Making a "BIODIESEL" Powered Car




About: cooler than you.....

Most People Don't realize A diesel engine can run on used deep-fryer oil

This by no means is a perfect method, or the best way to do it, just an easy Way to learn for beginners to get into this. Consider it a first step to living a GREENER life.

(this instructable is a continuing WIP so the more we share and learn the more it will be updated, please try to keep the criticism "constructive")

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Step 1: Must Have a Deisel Engine

As far as i know all diesel engines are capable of this. So if your car runs on diesel you're in luck.
Heres the v-dub tdi (turbo diesel injection) but others i know that have been done are Mercedes, Seat, Volvo, dodge, Chevy, Ford, Toyota, ect ect ect ect

So even if you don't have a diesel car, Take the one your driving now and trade it for a diesel car, its an investment in the earth and our future.

Step 2: Modifications?

The best part is there is no absolute need for any engine modifications, So really this can be a way to instantly start getting free fuel and saving the planet at the same time. Captain planet would be proud of you.

There are available mods you can buy or make, but aren't necessarily required. If you have the money to spend, then by all means go ahead.

Depends where you live, if it gets cold, think about a fuel tank warmer for the grease will start to solidify clogging your fuel lines and such. But an eaasy way around this is to run a mix of regular diesel and your bio-fuel to keep your fuel in liquid form.

Step 3: Getting Bio-deisel

So all you really need for bio-fuel is filtered deep-fryer grease, If you live in a moderately sized city this can be obtained easily. I live in a little place called Boise Idaho and there are people offering free grease on craigslist weekly, and you can even hit up local fast-food vendors. They usually have a big stinky tank of it out back and usually have no objection getting rid of, you'll just need to get some big barrels or drums to put it in.

Step 4: Filter the Grease

Basically what your gonna try to do is strain out all the little pieces floating around, I tried lots of filter methods. You can spend money on filters made for this but i found using a piece of thick cloth used as a screen over a bucket can work fairly well, it just might take a few times going through depending on what sort of fabric you use, but feel free to try other filtering methods. This can get messy but you'll learn techniques soon enough and will have it down to an art.

Step 5: Global Impact

The coolest thing about running Bio Diesel is that no wars are fought over the oil, it's organic, domestic, supports our economy, its a renewable resource, and it cuts almost all of a diesel vehicle's emissions by more than 50%

Step 6: Enjoi

Fill er' up,
You are now driving a cleaner, healthier, GREENER vehicle.

So if you drive a diesel vehicle I hope you take in how easy this is and how much of an impact this can have if everyone follows suit and helps with the big problem. So even though it's not 100% Eco-friendly and the fact that this one act wont change the world, It's a step towards the final goal. Everyone has to play their part.


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    44 Discussions


    Reply 4 years ago on Introduction

    Does anyone have general cost assessment for converting a boxtruck 14' or larger to bio diesel?


    8 years ago on Step 4

    hey man!! WVO (wasted vegetable oil) is a biofuel, BUT IS NOT BIODIESEL!!

    For practical effects, you can add WVO (filtered of course) blended whit diesel to a diesel vehicle, BUT NO MORE THAN 30 - 40%. If weather is cold, no more than 10 - 20%.

    To get biodiesel WVO needs some chemical proccess (http://www.biodiesel.org/resources/definitions/) , and you can use it 20%, 50% even 100% without modifying your vehicle.


    11 years ago on Introduction

    I have had enough people email me about this device of mine that I am going to copy/paste an email I sent to one of the people. It might digress - sorry. Maybe someday i will make an instructible out of this - it should be one! I was teaching chemistry in a Christian school when doing an electrolysis experiment. It hit me that I was breaking water into the two most combustible gases there are - so why not use it under the hood of the car? A current flowing through water breaks the water molecule apart into Hydrogen (H2) and Oxygen (O2). The more amperage, the more breakdown, therefore the more gasses produced. A catalyst helps the process. I have researched to find if anyone knows how this works (actual process - like from the electron's point of view) - but to no avail. However I do suspect it has something to do with the 3 dimensional shape of the water molecule - I have a theory - but that is not for here! Construction: Parts: Wal-Mart - 6 inch or so diameter clear plastic food container w/ hinged top and clipping front. Approx the height of a one liter bottle - the closing top has two layers to it with airspace in between. Dollar store - two stainless steel barbecue spoons/forks/or spatulas. Lowe's: - tube of silicon sealer, two bolts that will be long enough to go through both layers of the plastic container's lid and have some left over - enough to attach a wire to the top (using a wing nut). 4 nuts for the bolts and two wing nuts. I suggest stainless steel bolts/nuts (wing nuts need not be). - plastic or metal, hollow 90 degree-angle-bent tube from plumbing area - I chose one with threads on one end. - Plastic, sort of rigid, clear tubing that is long enough to reach down to the bottom of the plastic container if a hole was drilled through the top of the container and the tube inserted - leave enough room so there would be a little sticking out at the top - this is called the VENT TUBE. - plastic (or metal) T-connector - this will T into the air-line which your PCV valve attaches to the carb. or injector housing. Find this and see what size hose i uses. You wil need probably about 2 feet of this hose and a suitable T-connector for it. I put the silicon sealer around all bolts where they meet the plastic lid. This makes it more airtight. The more airtight the construction - the better. Overview: The two stainless utensils will be used as electrodes. They will be bolted to the inside top of the plastic container (the top will not be hinge-fit anymore - the hinge mechanism is one of a type you can easily pinch it to disassemble - unclamp the top of the lid, and lift).. The 90-degree-tube will be an oxygen and hydrogen outlet and is also attached to the lid such that it will allow air to enter the plastic container. The plastic, rigid tube will be inserted through the lid and made to go almost all the way to the bottom of the container. This plastic,rigid tube will be the air intake. The vacuum line from the PCV valve to the carb/fuel-injector-housing (whichever you have - probably the latter), is cut, the T connector is inserted, the 2 foot of tubing (or whatever length it actually takes you from this T-connector t where you mount the unit under your hood) is connected to the T-connector. The plastic container is filled with water and a tablespoon of Epsom salts. The top (with electrodes, 90-degree-bent-tube, vent tube, and attached electrodes) is inserted. A wire from one battery terminal is attached to one of the bolts sticking out of the top (hence connecting the stainless utensil) and a wire from the other terminal is attached t the other bolt. Theory of Operation: The vacuum line from the PCV/fuel injector assembly creates a vaccum in the plastic container - this pulls air in , through the water, from the vent tube. the battery is connected by wires to the electrodes and therefore electricity is used in splitting the water into Hydrogen and Oxygen (both highly combustible). These gasses are created as tiny bubbles off of the electrodes and rise to the top, impregnate the air there, an exits from the unit through the 90-degree-tube. These gasses seem to aid in the combustion of the gasoline in the engine (only 20% of your gas is actually burned in a normal engine - 80% is - literally - wasted!). I am not sure if they actually are aiding combustion or are taking the place of some of the gas and being burned themselves. I add 1 tbsp of Epsom salts, but was starting to experiment with other chemicals - these just aid in the breaking down of the water and therefore more gas is produced. I once tried to see if greater than a tablespoon made more gas - nothing seemed to change. Recently I have heard of people using baking soda - I want to try this. I also saw on a website that someone is, instead, coiling two wires around the inside of the container. It might make more gas this way - I use stainless b/c it does not seem to deteriorate as quickly - and the electrodes are cheap at $1.00 each! Construction: Drill two holes in the top at about the 3:00 and 9:00 positions for the electrodes. The bolts will extend down through these holes. The stainless utensils should have holes in the handles already - bend the hand over such that the hole will be able to be put onto the bolt. Put the utensil on the bolt and insert the bolt UP THROUGH the hole such that the threaded end is coming up through the top of the container. Put a nut onto the bolt and tighten it. Put a wing nut on the top of the bolt so that it will be able to hold a wire onto the bolt. Make sure the electrodes do not touch each other and are not so long they cannot fit into the assembled unit - cut off (or better - bend the extra so as to make more surface area for gas production - but make sure they are not close to each other or they short out during operation). After both electrodes are in place, drill a hole at 12:00 and at 6:00 n the top. Make sure that one of these will allow the vent tube to pass through and put it in place (silicon or whatever it takes to hold it there - my hole was just big enough to securely hold the tube). Insert the plastic tube so that its bottom is just off of the bottom of the plastic container when the unit is assembled. Insert the 90-degree-output-tube into the other hole (again, my hole was large enough just to thread the piece in with little effort). Attach the air hose to the 90-degree-output. Attach the other end of the hose to the T-connector. Attach one wire to the red battery terminal. Attach the other wire to the frame of the car (make sure it is a place where the paint will not inhibit electrical contact). The frame is attached to the other battery terminal - but i use the frame so there is o danger of creating a spark/explosion of the battery. When you attach the battery, you will start producing glass. Therefore I found a place (a fuse box is a good place to look) that was "hot" only when the car was running - I attached the wire from the electrode that WOULD have gone to the red battery terminal to this spot and therefore gas is only beinf produced when the engine is on. I have now seen similar devices selling online for up to $1200.00! I don't think just the gas companies are greedy! This should cost around 15.00 max to make. B/c of the day we live in I add you make this/use this at your own risk. This is jut a record of what I personally have done/used since 1998 or so! Sorry no pic - if I can get it off of the other HD - I will try to remember to send you a pic - please let me know how it goes - it is NOT as difficult as the explanation would seem to make it! Also, if you respond to this email, and I can get the pic, I believe I even have part numbers on the pic I made!

    5 replies

    Reply 8 years ago on Introduction

    If you are still out there, I'd love to hear an update on your project- thanks for sharing!


    Reply 8 years ago on Introduction

    I am still out here - but unfortunately me health condition nowadays I cannot get out and do the things I want to anymore. If you do some searching here on instructables for things like Hydrogen, electrolysis, you will find some good posts.

    Well - there are a couple of diagrams I posted on the web one day:
    start here:
    and click the "next" button in the upper right to see all 3 pics.

    Also, I now that someone has made a circuit for something like 20.00 you can buy b/c the O2 sensor in cars might alter the way the engine is working when you start making/putting more O2 in. The circuit makes the computer ignore the extra O2 and so you get the mileage increase. I think that info is in instructables also.

    And here is a link to a post on this topic that I think is the best I have seen:

    If I could get around like I wanted, this is probably what I would be trying next. I hope you can get one working.


    Reply 11 years ago on Introduction

    Hello, What mileage improvement are you seeing with your gas injection device? What type of vehicle are you using it on? In cold weather, is there any problem with its operation? Thanks, Mark


    Reply 11 years ago on Introduction

    During the winter I was in Erie, PA - the PA snow belt. Since I was using Epsom salts for the catalyst I had little trouble. Sometimes it was actually cold enough to freeze the salt water, but this just meant until the engine warmed the water up, there was no H2 and O@ being made. It was first on a, '83 (?) AMC 4WD Eagle. Then I had it on an '85 Chrysler. Health problems got in the way after that. The last vehicle I had it on was a '94 Olds Silhouette van. Anywhere up to 30% is average (it has been put on other friends cars). The Chrysler doubled its mileage from 200 miles on a tankful to 400 miles on a tankful. The Olds van had it on it for only one day before my son took it off for inspection (yearly here in PA). He dd not realize you simply need to disconnect only the one hose for it to pass PA standards which dictate a car will not pass inspection if it has a gas saving device on it - however, it is legal to install them! So I never got the mileage off of the van. My one friend who still sells the book i wrote about it says out of the feedback he has gotten, the average has been 35% increase on fuel injected or carb. cars. I know my one friend with an older AMC Jeep Cherokee was getting an unbelievable 67 mph. But he used the AC pump connected with the system to force feed the O2 and H2 in to the carb and not just rely on the engines vacuum to pull the gases in.


    8 years ago on Introduction

    Actually the correct definition for TDi is Turbo Diesel Intercooled. Most modern diesel engines have intercoolers to enable a higher mass of air to get into the engine at any given time. A lot of pick-up trucks don't have intercoolers hence the designation TD. Those without turbos just have a "D" in the designation.

    All diesel engines are direct injection, it the only way to get the fuel to burn at the correct time. It doesn't work like a petrol (gasoline) engine which mixes the fuel with air at the intake. Diesel engines work with too much air, throttling is done by controlling the amount of fuel to burn, unlike petrol engines which require a precise mixture of fuel and air to burn properly. There is no butterfly in the intake to control the airflow in a diesel like on a petrol engine.


    9 years ago on Step 1

    Minor correction: TDI stands for Turbo Direct Injection.


    10 years ago on Step 6

    I have a '96 F350 with a 7.3L diesel and I have been running vegetable oil for over a year now. Beermkr is right about heating the oil in that it makes it much easier for the engine to pump, but at first I had no heater and the only problem that I encountered was a lack of proper filtering that clogged my fuel pump. One new fuel pump, two more inline filters, and a heat exchanger later, I'm rolling along making people hungry. Law


    10 years ago on Step 6

    I have also heard that untreated veg oil can damage the rubber seals and pipes in the fuel system. In general, the older the vehicle, the less damage is likely to be done. A friend of mine has a Landrover Discovery TDi and has sucessfully run a mix of pump diesel and filtered veg oil. Start with a small amount of veg oil in each tankful of diesel and increase the ratio on each fill. Problem is that you wont know the safe maximum ratio until you damage the car ;-( In this case, my friends car is worth about £1000 and his other car is a much more modern Mercedes E class diesel.... which he only runs on pump diesel.


    10 years ago on Step 6

    If you do this and run straight oil in your car you will destroy it. Veg oil is too think to be used without heating it or converting it to true biodiesel. If you use this instructable you will make an expensive injector pump or engine into a worthless piece of metal.


    10 years ago on Introduction

    A bit late to the party, I know - how do you handle the odor that this used oil produces? I've got an old truck that I've considered converting to diesel to capitalize on this, but my wife says that it isn't gonna happen unless we can do something about the smell. Unfortunately, it's a wasted project to start on unless I can solve that problem to start with or I'll be in the doghouse for months. Any suggestions?