Biodiesel Equipment Hacks


[Oldman] took on a biodiesel project for some friends a few years ago. A fully operational processing rig was never achieved, but he did document some of the successful hacks he came up during the project.

The idea is to reclaim the waste oil from restaurants and burn it in your modified racing motorcycle or other mode of transportation. That makes it sound easy, but have you ever seen what happens to bacon fat after it cools? Granted, we’re talking oil from vegetable sources but the same type of coagulation presents itself. Pumping it through a processing rig becomes especially tough in the winter, and that’s why [Oldman] came up with the heated pump head on the right. It’s got three connections; two are part of a loop of copper tubing, allowing 150 degree water to be circulated to liquefy the grease. The third connection sucks up the melted oil. You also need to regulate the water content of the fuel. The inset images of a salad dressing jar are his test runs with applying vacuum to dehydrate the fuel. He learned that it needs to be heated slightly to reduce foaming. He had planned to scale up this concept to apply vacuum to fuel stored in propane tanks.

18 thoughts on “Biodiesel Equipment Hacks

  1. What is the deal with the nonfunctional or unfinished hacks lately? I mean, it’s fine but it’s not like biodiesel hasn’t been made thousands of times before. If this was cutting edge, then sure.. it’s a WIP. But this, well, didn’t even work.

    1. I was pretty surprised at how well the auger worked at pumping congealed grease. Anyone who has pulled up to a grease dumpster in the dead of winter would appreciate a fast and efficient way to fill their jug. So it’s not cutting edge, well, there might be someone who would like the info.

        1. Yeah there are proper wrenches for it. Assuming you’re not worried about distorting the valve body, get yourself a Johansson/Swedish type pipe wrench. Unlike a Stillson wrench(the ones with a knurled nut to adjust the jaws) they grip the jaws together when the two arms are pushed together, so more turning effort=more grip. A threaded nut adjusts the point/angle at which the jaws start to close. and with care you can slide a heavy piece of tube over the end, to both get the huge leverage needed, and to arrange for the extension bar to keep the wrench clamped on to the valve body. Wrench I used was about 24 inches long, and I needed about double that on the extension.

          Clean out the top of the thread as best you can, add a penetrating oil, leave at least overnight. Place tank on it’s side, and place a long length of thick wood through the tank’s carrying handles to react the torque/stop the tank rotating- you’ll probably have to sit on the tank too! Clamp the wrench on the side of the valve body, and against the side of the connection for the regulator. Then begin to apply torque, and more torque… Not long after the valve body begins distorting the thread should emit the most horrendous squealing noise, and shift just a tiny little bit bit, before jamming up again. At that point stop add more penetrating oil and leave for a while again. When you come back to it, rock the thread back and forth, after each rock it should get looser and looser. Similar kind of action as that used in hand tapping, where you do one turn forward, half turn back. Keep adding oil to kill the friction- those threads get pretty hot, while you’re trying to undo them. As you exposed more thread it gets easier and easy, and eventually a sliding spanner will do, the job, and you don’t need the reaction beam. complete the unscrewing outside, and well away from sources of ignition, as when the valve comes off, it will utterly reak of propane/mercaptans, and you’ll almost certainly want to be sick. To reduce risk until you feel up to cleaning the tank out properly you’ll want to plug that hole pretty quickly. Simplest to put the valve(or a blanking plug- think it’s a 3/4″ pipe thread) back in and at least hand tighten before you leave the tank, but remember it might leak a little.

  2. I used the freezing weather to separate most of the oil from the water, then warm the bottom of my barrel a bit and turn on the valve I have there…when I start seeing more oil than water, I know I’ve removed most of it. THEN I heat the oil and worry about the next step. You supposedly don’t have to worry about most of the water(as long as it’s not above 1% or so) in the transesterification process because the water merely means it converts the glycerine to soap. You may have to add more catalyst but it still works fine.

    Also, I hope you aren’t using the oil without transesterification. If you’ve ever burned oil in your frying pan and noticed that layer of sticky stuff that never seems to come off without hard scrubbing, that same stuff sticks to the walls of your cylinders and quickly ruins your rings. If you think it’s a joke then send a motor oil sample from a car that has never been done this way and then after about 3 months of use of straight WVO send another motor oil sample and see how it changes. I’ll guarantee you’ll be very surprised.

    1. Yes. Running without modifications on the wrong engine is a bad idea.
      But it’s not as simplistic as you suggest.
      I’ve done a good 50K miles with an unmodifed engine, then after installing FPHE, another 100K miles on it. Now on the next car (body rotted out) which needs to start and shut down on diesel, but runs SVO happily for the last 80K miles. Water injection under boost has been show to solve ring gumming issues, but I aint suffering from them yet so don’t use it.

      1. Did you get your motor oil analyzed before and after the conversion? I’ve never heard that water injection actually solved the problem from anyone who had done so. My car model clocks in at 1 million miles average lifespan and this model holds the world record for the longest lasting car at 3 million miles. Diesel engines in general last longer than gas engines because they’re built to take the compression,etc. so a “test” of 80k without oil analysis isn’t telling me much if you’re merely watching for ring gumming issues.

  3. Always sad to see a biodiesel project. I ran straight WVO (waste veggie oil) for 5 years with no problems. The only reason I’m not running WVO now is because I’ve moved and don’t have a source for WVO right now.

    For those that don’t know, for Biodiesel you convert the fuel (used veggie oil to Biodiesel). To run straight WVO you convert the vehicle. I dewatered and filtered (to 1 micron nominal) my WVO for 9.1 cents a gallon (electricity for heating to dewater it and filters – both at the processing stage and on the vehicle).

    Biodiesel creates a lot of waste – lye soap. Biodiesel needs a lot of nasty chemicals to convert it and produces vapors so nasty you have to capture them. Biodiesel also costs $1-$2 per gallon to make. I have no reason to pay more per gallon, just to spend more time making biodiesel using chemicals I don’t want around my house (whether children are there or not).

    The only waste I made while processing WVO was dirty filters (that lasted 770gallons, 1500gallons and 3000 miles each), and the occasional draining of the oil water mix from the bottom of the processing tank. My processor was dirt simple, the only controls it needed were one switch (on or off) and one valve (open or closed). My oil passed every “hot pan test” it was subject to.

    There are only a few reasons rational people go the biodiesel route:
    1. They don’t know WVO is so much simpler, cleaner and better.
    2. They don’t want to convert a lot of vehicles (an entire fleet).
    3. Govt Subsidies – money talks and they’ve thrown a lot of money at “green” projects that haven’t worked, just look at all the govt financed solar companies and electric car battery companies that went out of business.

    Not surprised at all to see it unfinished, I don’t have a problem at all with this unfinished project. After you count your time and fuel to pickup the veggie oil to process it into biodiesel, then you’re breaking even on cost per gallon or your time is free. I hope the lesson people learn here is that biodiesel is great for people who like to do a whole lot of work to get a govt check, because if you’re not getting a govt check to make biodiesel, then you’re probably much better off to buy diesel at the pump or get serious and run WVO.

    People who get WVO wrong and give it a bad name are people who don’t filter it adequately/correctly, and/or don’t dewater it fully, or don’t fully purge their systems before shutting off their vehicles or don’t let the WVO temp get hot enough before they switch over to WVO when driving or they don’t change their vehicles fuel filters often enough.

    Run clean, dry WVO, through clean fuel filters when the engine is fully warmed up, and completely purge it of WVO at the end of each trip and you’ll be fine for years.

Leave a Reply

Please be kind and respectful to help make the comments section excellent. (Comment Policy)

This site uses Akismet to reduce spam. Learn how your comment data is processed.