Edmunds dealer partner, Bayway Leasing, is now offering transparent lease deals via these forums. Click here to see the latest vehicles!

Okay, I'm switching to BioDiesel!

Mr_ShiftrightMr_Shiftright Member Posts: 64,481
edited March 2014 in Mercedes-Benz
One of the vehicles in the current Shiftright Fleet is a Mercedes 300D and I've decided to try running it on 100% biodiesel fuel, commonly called B100 at the pump.

It sells for a painful $2.69 a gallon here in Marin County, California, but the big Benz is quite economical for its size and it's mostly a second car these days anyway.

I invite anyone else who is using or intends to use biodiesel and perhaps we can share experiences.

Info on biodiesel is available at www.biodiesel.org, but most of the Q&A requires Adobe Reader.

The mere thought of my car smelling like the grease from french fries (oops, I mean American fries) is irresistable.

So far the only precautions I'm taking prior to first fill up are 2 new fuel filters and 2 new pre filters, which I will change right after the first tankful of B100 is consumned. B100 is a very good solvent and will clean out residue slime and algae as well as make the injectors squeeky clean again. With the Benz double filter system, any gunk will be trapped before it gets to the expensive parts (oh, we hope!).

The fuel lines in my car are all steel or plastic so I'm not expecting any rubber hose deterioration issues.

Lessee...$2.69 a gallon at 26 miles per gallon ...well that's about 10 cents a mile, so it's about the same as a large V8 sedan getting 18 mpg @ $1.75 a gallon for gas. Not too bad.

Of course the point isn't that this old Benz can compete with a modern V8 sedan is any meaningful way (except smashing into it and vaporizing it) but that many of the nastier diesel emissions are eliminated in dramatic fashion and that the source of biodiesel is domestically produced soybean, other veggies I guess (hemp?) and restaurant grease. It's sorta patriotic I guess.

I am a bit worried if inhaling the exhaust will raise my cholesterol levels, but I suppose that's an acceptable risk.


  • 0patience0patience Member Posts: 1,712
    Filter, filter, filter and expect a few leaks to pop up in the injection system if there are any weak links.
    Not likely with the Benz injection system, but the Ford 7.3 has a tendancy to leak out the injector line o-ring.

    Other than that, there are many sources that show you how to make your own bio diesel on the web and I know a few folks that run it on their farm trucks.
  • Mr_ShiftrightMr_Shiftright Member Posts: 64,481
    I think I'd probably be strung up in Marin County for cooking soybeans and french fry grease in my backyard, but thanks for the heads up.

    The Benz injection system on this model is, of course, completely mechanical and very sturdy, so I'm not expecting any issues there, but I have an armload of filters handy just in case.

    I have been troubled by visible smoke emissions and haven't been able to completely eliminate them on this car, no matter what adjustments I make, so I'm hoping the new fuel will help with that.
  • mullins87mullins87 Member Posts: 959
    We are beginning to see a couple of the wholesalers starting to retail the stuff. I haven't called to find out the mixtures or the prices yet, but I will be soon. If the price is reasonable, I'll be trying it.
  • Mr_ShiftrightMr_Shiftright Member Posts: 64,481
    It's $2.69 a gallon where I am, but we have historically the highest gas prices in the known universe, so....

    I'm going to use 100% mixture. That way if it runs okay on it, I know I can mix with fossil fuels no problem.

    Actually "fossil" fuels is just old plants and this stuff is new plants, so the fuel is a lot "fresher" right? :)

    I bought three primary and three secondary filters so I am armed and ready.
  • mullins87mullins87 Member Posts: 959
    I just talked to one of the distributors around here that sells bio-diesel. He only sells off-road diesel blended. However, he is selling B100 for $2.50 a gallon, retail price. I could probably get it cheaper if I could buy in bulk. He told me his biggest expense associated with this fuel is the transportation cost to go get it. It is rumored that a new "refinery" making bio-diesel will be built within 50 miles from here. That should help with the cost considerably.
  • Mr_ShiftrightMr_Shiftright Member Posts: 64,481
    I think they call that "ground to tank" costs (earth to refinery to gas station to your car's tank).
  • mullins87mullins87 Member Posts: 959
    I just got off the phone with the local biodiesel distributor. He called to tell me the price went down from $2.50/gallon to $2.00/gallon!!!! This is for B100. This is great news. There have been two reason why I have not jumped on yet. The first reason being availability. but now that someone local is carrying it, great. The second reason being price. I understand the benefits of running even a B2 blend. But now that the price is this low, a B20 blend will still be feasible.

    I have read in other places that you can burn B100 with no problems. This guy is suggesting to stay under a B20 blend due to a rubber compatibility problem. Anyone have any ideas?
  • mullins87mullins87 Member Posts: 959
    I was doing some rough calculations. My current fuel price is $1.399 per gallon. Using a B10 blend, my overall fuel price will go to $1.447 per gallon and a B20 blend will only push the price to $1.504 per gallon.

    If there is someone out there that can provide me with solid reasons not to give it a try, please do so quickly. I'm sold on the idea.

    Oh, one more question. What is the shelf life of biodiesel?
  • Kirstie_HKirstie_H Administrator Posts: 11,148
    Should one anticipate getting roughly similar MPG numbers with Biodiesel? I'm intrigued by the idea but 1) haven't heard of anyone carrying it around here, and 2) I don't buy first model years; i.e., I'll let someone else try it first!

    Shifty, any results to report yet?

    Roving Host & Future Vehicles Host

    Need help navigating? kirstie_h@edmunds.com - or send a private message by clicking on my name.
    Share your vehicle reviews

  • Mr_ShiftrightMr_Shiftright Member Posts: 64,481
    Nope. I'm waiting for my E service to be done on the car. That requires a total filter change which is what you have to do when you switch to biodiesel. Both primary and secondary fuel filter.

    I don't think there is any problem with rubber seals, etc. the only problem is that the biodiesel is a reall good solvent so your gas tank, etc will be made squeeky clean---hence the need for new filters.
  • mullins87mullins87 Member Posts: 959
    Are you running B100? Have you noticed any performance differences or noise changes? Will biodiesel absorb water more quickly than petro-diesel and will it support a healthier crop of algae?

    The reason for the water and algae questions is that since I am not going to try B100 at first, I'm looking at some short term storage issues. Also I'm concerned because I don't think the biodiesel tank at the distributor sees very many turnovers as do the petro-diesel tanks.

    Kirstie: I've been told, hence I have not verified it on my own, that biodiesel has fewer btu's per gallon than petro-diesel. I don't know where to go find such info. It could be that with the B20 blend I plan on running that I may not see an appreciable difference. However, if I try a B100 blend like shifty, it could be that I'd see a drop of 1 to 2 mpg.
  • Mr_ShiftrightMr_Shiftright Member Posts: 64,481
    I only ran one tank as a test, then swapped out the secondary filter as a precaution, then went right back to regular diesel. I can't say that I noticed any substantial difference with B100, maybe a little less power. I've always got my foot to the floor in that car anyway, so it's hard to tell. It did seem to smoke a bit less when I floored it at night and watched the headlights of the car behind.

    I found two other people using B100 and they report no issues so far, but they are newbies, too.

    I'm not switching to regular B100 use until I feel confident that I've read everything. Also, the price jumped way up in Marin County just as I was ready to switch.

    I guess, okay I admit it, I'm a bit nervous yet. My Benz has been such an outstanding car that if I messed it up I'd kick myself multiple times.
  • bhill2bhill2 Member Posts: 2,472
    If you are, I would be very interested in any updates you have. I live in Sonoma County, so we are fairly close neighbors. I don't presently own a diesel but have in the past and if biodiesel were practical it would considerably increase my interest in owning another one.

    2009 BMW 335i, 2003 Corvette cnv. (RIP 2001 Jaguar XK8 cnv and 1985 MB 380SE [the best of the lot])

  • Mr_ShiftrightMr_Shiftright Member Posts: 64,481
    I have mixed feelings about it. The "pump biodiesel" works well if you change out the filters but it is expensive and I have no idea about any long term effects.

    Using restaurant oils, etc, is a whole other matter. A great concept but not so easy. You need to study up on the modifications you need to do this, and of course you have to be willing to go through the hassles of collecting, storing and filtering this stuff.

    I think for the young and energetic types who have time on their hands to play with this, it's great, but for me, paying $3 a gallon for pump biodiesel doesn't make a lot of sense.
  • bhill2bhill2 Member Posts: 2,472
    Thanks, Mr. Shiftright. I am neither especially energetic nor (unfortunately) young. I am assuming that the fuel filter swap only needs to be done once, or at most a couple of times, and then all will be well. Is that right? Is there any buzz about whether biodiesel has enough visibility as a domestic substitute for imported oil or as a low-emission alternative that the price might somehow be moderated? As may be becoming obvious, I am not young or energetic, but I am persistent.

    2009 BMW 335i, 2003 Corvette cnv. (RIP 2001 Jaguar XK8 cnv and 1985 MB 380SE [the best of the lot])

  • Mr_ShiftrightMr_Shiftright Member Posts: 64,481
    Well the US uses so much of the world's oil supply that quite frankly, doing the math makes me realize that no amount of "conservation" could possibly get us off the oil teat or even seriously dent the addiction.

    so I don't see biodiesel as a solution to anything, but I think using it puts people in a certain frame of mind which is a good thing. There is something very satisfying about converting someone else's garbage into your mode of transport.

    I think if I read correctly that there is a third alternative to a) restuarant waste oil and c) pump biodiesel, and that would be buying bulk commercial clean cooking oil and using that. But I think you still have to treat it chemically to break down the large molecules so that it will flow in colder temperatures.
  • moparbadmoparbad Member Posts: 3,870
    Biodiesel quality varies considerably and is not regulated for fuel quality. It can cause substantial problems with injection pump. VWOA will invalidate warranty for any damage due to biodiesel.
    Good quality biodiesel will not cause problems with older or modern diesels.
    Cloudy color and off odor are easy indicators of poor quality biodiesel.
    Know the risks and how to evaluate biodiesel prior to use.
  • gagricegagrice Member Posts: 31,450
    I think this is a good outfit to contact with questions. They are making Biodiesel and selling it at a profit. Proves it can be done.

  • blackstone3blackstone3 Member Posts: 29
    I found that the 100% BioDiesel that I was using gelled at cold temperatures. I think it was below 20F. I was using Bio for a forced hot air heater and it all gelled up. So if it gelled in the heater why wouldn't it gel in a car?

  • Mr_ShiftrightMr_Shiftright Member Posts: 64,481
    That's about the gel point for biodiesel, around 23F. Biodiesel is not as tolerant to cold weather as petroleum based diesel, the latter capable of working okay down to about 5F or zero.

    You have two alternatives. One is to add 30% regular petro diesel fuel to your clean biodiesel, and another is to buy an antigel agent made for biodiesel, such as is shown here:


    Your biodiesel get point is also determined by the formulation of your biodiese--whether it is from "virgin" oil or recycled stuff. The purer the better, but also the more costly.
  • gagricegagrice Member Posts: 31,450
    That was an informative article on Biodiesel. Another good solution is to go South for the winter, just kidding. I think where I work in the Arctic they just keep mixing more # 1 diesel in the tanks as the winter gets colder. I know #2 will gel at about -20F. I have never had a problem with number one diesel even at -50F for an extended period of time. It seems like a lot of work to be a good environmentalist and use Biodiesel. Maybe when ULSD is mandated we can mix in the winter and keep a clear conscience.
  • ahousahous Member Posts: 5
    gagrice, I personally haven't paid too much attention to the cold weather issue, but there's a whole section on it in the discussion at www.biodieselnow.com
  • gagricegagrice Member Posts: 31,450
    ALBANY, NY -- (01/28/2005; 1630)(EIS) -- Two New York metropolitan area oil heat dealers are introducing "Biofuel," (B-20) a blend of 80 percent low-sulfur fuel oil and 20 percent biodiesel, that is refined from soybean oil. The heating market introduction is funded by New York State Energy Research and Development Authority (NYSERDA) and is aimed at reducing air pollution and petroleum dependence among oil-heated homes in the metropolitan New York area.


This discussion has been closed.