Converting a Detroit Diesel Engine to Biodiesel

I couldn't have said it better, using biodiesel is no problem, finding quality fuel can be.

here's a proper link http://www.biodiesel.org/resources/biodiesel_basics/

Don't know what's wrong with the one you provided? when I drag & drop it works?

I think it has something to do with bathing a golf playing gooney bird

I know the Detroit Diesel engine family pretty well and the 6-71 (a very old 2-stroke design) is out of production. So you must have a dealer rebuilt or used engine. These were common in older city buses in North America in the 1970s. I doubt there is much if any warranty to worry about. But they can certainly burn biodiesel well with a clean filtration system and at reasonable ambient temperatures. The main issue with biofuels or biofuel blends other than quality (dirt, chemical composition) is the temperature at which it will become cloudy and flow poorly through filters, small holes and inside your diesel unit injectors. The cloud point for various 100% pure biofuels is around -3° C to +11° C—much higher than the cloud point of petroleum diesel. Crystals of paraffin wax begin to form at the cloud point. Biofuel blends (5% to 20%) tested in Winnipeg Canada, ran into significant problems during the cold winter in the last few years. For more technical details look at ASTM D6751 - 08 Standard Specification for Biodiesel Fuel Blend Stock (B100) for Middle Distillate Fuels

Biodiesel is an exellent solvent. It can attack some seals and gaskets. It can also clean sludge from tanks and lines. If you run 20 % or higher, especially 100% biodiesel, you may find your fuel filter clogs. Don't blame the biodiesel for clogging it. It cleaned the sludge out of your system and the filter caught it. Be prepared to change your fuel filter after the first couple of tanks.

I agree with wcfloyd, the other factor is that biodiesel will act as a solvent and flush deposits in the old lines and the fuel tank downstream into the filters. It is highly recommended to change the fuel filter as he says.

The attached link to an EPA fact sheet has more recommendations:

http://www.epa.gov/smartway/growandgo/documents/factsheet-biodiesel.htm

Some good responses there. I would like to run 100% (make my own) and I currently use the engine coolent (through a bypass system) to heat our domestic water (shower, sinks) so I thought, with some additional hoses and bypass valves, shut offs I could build a similar system to preheat the bio-fuel. That way I could run-up on regular diesel until the bio-fuel reaches an acceptable temperatuure and then (with an additional valve) switch over. prior to shutting down I would switch back to regular diesel to purge the system of the bio-fuel thereby reducing the solvent action on the seals. I have four 100 gal tanks in series and I was thinking of dedicating two to bio-fuel. Am I dreaming or does this sound doable.

That is very do-able. I have a '84 diesel Benz that runs on used cooking oil. There is a supply line that runs from the radiator to the cooking oil tank which has a heat exchanger in it, and returns to the other side of the radiator. The fuel line runs thru the supply line coming to the heat exchanger in the cooking oil tank. This heats the oil in the tank, and heats the cooking oil on the way to the final fuel filter. There is a copper coil wrapped around this final fuel filter to heat the filter. This coil is tied in with the coolant system going to the heat exchanger. There is a toggle switch to go from diesel to filtered cooking oil going to the injectors. It operates solenoid valves that are open for oil and closed for diesel and vice versa. I warm up on diesel, then switch to cooking oil , then switch back to diesel prior to shut down, just like you envision. If biodiesel is home-made and cloudy, it likely has water in it. The final fuel filter should have a water separator and drain in the bottom. Use the kind with a clear chamber housing the filter element so you can see any water in it. You probably wouldn't want to heat both bio tanks at once, so you should ba able to have hot colant flow to one and not the other, and be able to switch when switching fuel tanks. Put your valve on the return side to control which tank you heat, so your fuel line can run thru the supply side.

This is exactly what I'm looking for. I'm really excited. Is this a system you put together? If so would you be willing to share with me the layout and component types. By your description of the combination of components and their uses these are not stock parts. Rather genius I might add. Do you have seperate fuel filters and pumps for each fuel type? How many filters do you incorporate? So many questions; I'm looking forward to hearing back from you.

Biodiesel is a direct replacement for diesel.

What you're talking about is WVO [waste vegetable oil], you won't have seal problems, but WVO will crud up your motor over time & emit more pollution than regular or biodiesel & wvo isn't actually legal. There is the pesky matter of the federal & state road taxes you'd be avoiding.

Then again a 2 stroke DD isn't exactly a very emission friendly powerplant.

The link I gave has a WVO section too. Here in california wvo will only fly for a couple more years & then Diesel's will need smog check also.

Still whatever pays the bills LOL

I bought a kit on line from Greasecar and had my mechanic buddy install it, but you can find the components on the shelf if you can spend the time to look for them.My mechanic buddy had the injector pump rebuilt with teflon-coated pinnels,because he thought that would be less likely to stick than stainless steel. I use a separate filter for the cooking oil. The original stock fuel filter is used on the diesel line. I find the most critical elements are selection of oil and filtering the oil. Avoid fried chicken and sea food restaurants. They generally use partially hydrogenated oil which is solid at room temp. This can clog up your arteries as well as your fuel lines and filters.The local Mexican restaurant has the best oil I've found. Other restaurants fry food with a lot of breading and flour, which is hard to filter out.I actually had to wash the oil with water to get the breading out, let the water settle out, filter the oil and dry it by heating to boil out water. I filter thru a 100 micron nylon filter bag to remove the crunchies. (A nylon stocking will do just as well for this first filtration.) I then gravity filter thru a 25 micron bag, a 5 micron bag, and finally a 1 micron bag. Cold filter the oil-do not heat it to filter. Crud will melt, go thru the filter, then crystalize out upon cooling. If possible, I like to pour this 1 micron filtered oil thru another 1 micron bag to a storage tank for settling, and draw out of it for filling my tank. And I still run it thru a 1 micron bag going into my jerry can. These are the same filter bags used in chemical plants, and I buy a box of 50. I get 1500 to 2000 miles before I have to change the fuel filter on the cooking oil line. Before I went to the 1 micron bags, I got more like 500 miles.

Didn't know you were going to make your own, here's what I consider the best forum of Biodiesel home brewers: http://biodiesel.infopop.cc/eve/ubb.x

You haven't said where you're located. The cloudpoint will depend on the feedstock.

What are you going to do with the glycerol?

Methanol will literally melt your optic nerve, so be sure to have good fume control & methanol recovery if possible. If you think you've inhaled fumes or absorbed any through your skin, drink some hard liquor, it will help flush it out of your system.

Koh is nasty so be careful!

Water is the biggest enemy of quality BIO.

HAVE FUN

Wow, that's pretty scary stuff. Although I'm in the very early stages of research I assumed that biodiesel was easy to create; just pick up some used restaurant oil filter it and bingo you have your fuel. Maybe I'm using the wrong terms, I don't plan on making any blends, simply switch between between fuels.

Guest, Just like many thing you can read the warnings are scary. I you take your time to read the warnings and set up a good working space and use good practices you can minimize your risks. I have been making Biodiesel for three years now to heat my house in the winter (1600 gallons this year, cold winter). I have not had any adverse health issues. I did have some mechanical issues early on as the BD ate some of the seals in the fuel pump to the burner.

Bob

There's no need to convert your engine. Rudolf Diesel's original engine was actually intended to run on peanut oil.

That would be the fallacy of "Free Fuel"

For roadworthy biodiesel the best systems I have seen are going to clog a single car garage with equipment. Not free.

But, that said there are two steps in using oil:

WVO = waste veggie oil needs straining/filtering as described before

IVO = Industrial veggie oil, (or non-food grade) less filtering required once you get to know your supplier

Both contain glycerines that "should" be precipitated out - I say should because it has to do with the cloud factor your geography allows, as well as wear and tear on the engine. And that is where the really nasty chemicals come into play as well as producing glycerine that may be saleable.

So users, especially stationary users, are pre-heating the oil so they don't have to precipitate it and just buying IVO at (last I checked) .75 / gallon in bulk.

I don't know that WVO is actually too sustainable for the user, as eventually the market will get saturated with people willing to pick it up for free, then as new sources dwindle - buy it.