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Biodiesel, what to expect?

1878 Views 14 Replies 8 Participants Last post by  jeffnzie
I have finally filled my 85 300 D with a b20 biodiesel mix. I haven't noticed any difference in performance, yet. Has anyone been using biodiesel on a regular enough basis to know if I should expect anything from the car, eg. needing to change the fuel filters, gas milage, acceleration, etc?
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Running B20 you should not expect much difference in performance or economy. B20 is sold at about 100-150 stations across the country, the reason it is sold as B20 is because it has very little effect on your engine or fuel system. Should you decide to start running B100 you will see a noted increase in fuel economy and a gradual increase in performance as the carbon is cleaned from the inside of your engine. It is the higher biofuel ratios that require fuel filter changes before and during the first 1500-3000 miles. BTW, you may not be aware but gas engines can benifit greatly from biodiesel. They are capable of running up to a 15% mixture.
What are the risks of running biodiesel? Can this lead to engine failure in cars with high mileage? My mechanic claims to have seen an increase in blown engines since people have started to use straight vegetable oil. Has anyone else heard this? Do I need to change out hoses, etc. because of the methyl esters in the biodiesel?
The only two risks of running biodiesel I've ever heard of are clogged fuel filters and getting hit on by hippy chicks. The second is obviously not such a bad thing.

EDIT: I have read that the hoses don't hold up to the methyl esters as well, check out www.veggieavenger.com for more information.
I think I remember something to do about fuel lines and the new fluid--straight veggie oil might not be good (for the lack of a better term) for the old fuel lines, or might not be good for rubber-type fuel lines. A replacement might be necessary. But somebody who knows better might elaborate more on this.
engnenk - 2/14/2005 7:12 PM

What are the risks of running biodiesel? Can this lead to engine failure in cars with high mileage? My mechanic claims to have seen an increase in blown engines since people have started to use straight vegetable oil. Has anyone else heard this? Do I need to change out hoses, etc. because of the methyl esters in the biodiesel?
You are comparing apples to oranges. Biodiesel and SVO (Straight Vegetable Oil) are not the same thing.
In *some* early 80's engines there have reports of rubber component failure with the use of B100, primarily on the fuel line(s), however it is NOT a guarentee that this will happen.
As far as filters are concerned, there is a better than not chance that you will go through a couple filters while the B100 does it's job of cleaning out all the dino (fosil fuel) gunk that is left behind.
Benz has a screeen sedikent filter *inside* the fuel tank and this will get gummed up and bring you to a standstill, which means a tow truck. The way around tis is to strip the screening from it and install an in-line fuel filter at the outlet port of the fuel tank. This way when it gunks up (and it will) you can self change it in a few minutes (have a couple spares handy).
Other than that, your Benz will LOVE the B100, providing it is properly made and washed. you can look up various sites that give advice on this, but commercial (the most expensive way and not guarenteed to do better that you could). I personally prefer www.journeytoforever.org/biofuels as my source for how-to
I started making my own last year and my reactor/wash tank set up was ready in august, just in time to get ready for a holiday run. I ran B100 of my own making for the 600 miles (965Km) approx one way trip, fueled at the pump for a two week stay and omce the tank was down to 1/4 I filled it with the B100 I brought along for the return trip. The reaction was almost instant, the engine's noise levels smoothed right out. Power and mileage are about the same. I later had to change the fuel lines and screen sediment fliter, a costly affair as I had to have MB do it,not having the tools,space or talent to do it myself, hense the advice to strip the screen part and instal an in-line filter *outside* the tank's outlet port.
Once you have learned to make good fuel you will never want to go back. Only draw back is the cold. Below 40F (5C) it starts to gel unlss there is a high volume of talow (beef and pork fat)then the gel is higher yet.
To run SVO or WVO (Waste Vegetable Oil) you will need to modify the car's ability to accept these4. Most have used a two tank system and flip a switch to either the SVO/WVO once the car has attained operating temperatures (180F/82C)where the coolant from the radiator is run through the seconmd tank with a heat exchanger installed in it.Also handy is a heated fuel filter in the engine compartment to be sure that even on the coldest days the fuel entering the pump and injectors is plenty hot and the viscosity is such as to compare to regular diesel fuel.
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Thanks to the History channel I think diesel motors were designed to be used with a renewable fuel source for farmers. If I remember correctly peanut oil was the intended fuel. I imagine the compression ratios were not what they are today but the intent of the inventor may still come to fruition if prices get any uglier. BTW spoke with a trucker in upstate New York and he said if there were alternative fuels being sold locally he'd give it a try. I think it's the biggest part of his business cost basis.
On average, what has been the costn per gallon of making your own SVO/WVO fuel?
You don't make SVO or WVO fuel, that is free after you install a two tank system and filter the oil which costs pennies. You make biodiesel from WVO which costs about $.60/gallon

EDIT: Check out http://www.journeytoforever.organd
http://www.veggieavenger.com
you can find a slough of information about biodiesel on these sites...jouneytoforever is THE site for biofuel info.
I have a 300d turbo and I bought it to run On biodiesel...Here is what I have experienced...A DROP in fuel economy, not an increase, like steve said. Also, a loss of about 4-7% horsepower when running on B100. Also, mine runs hotter on B100. And it's more expensive. [:O] NOW, on the POSITIVE Side, it DOES clean your engine and it will run smoother, quieter, and smell like true "freedom Fries" do...Whatever that might mean to you [8D] I heard and have been told, "carry a spare fuel filter, each kind." Me being on my low budget, didn't, and never experienced any problems. My fuel filter was visibly clean when I bought it...If yours is dirty, carry a spare for sure, or have AAA PLUS. And in the winter time, don't run more than B45 I would say, in your tank at any time, because it gels, and will crystalize in your fuel filter and possibly cause damage. Otherwise, MAKE NO MISTAKE, BIODIESEL IS WORTH THE EXTRA $$$$$ AND PLEASE PUT IT IN YOUR DIESEL MERC NOW!!!!! KYOTO PROTOCOL ISN'T A BAD IDEA....RUDOLF DIESEL INVENTED HIS FIRST ENGINE TO RUN ON PEANUT OIL.
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turbosing777 - 2/16/2005 8:42 PM

I have a 300d turbo and I bought it to run On biodiesel...Here is what I have experienced...A DROP in fuel economy, not an increase, like steve said. Also, a loss of about 4-7% horsepower when running on B100. Also, mine runs hotter on B100. And it's more expensive. [:O] NOW, on the POSITIVE Side, it DOES clean your engine and it will run smoother, quieter, and smell like true "freedom Fries" do...Whatever that might mean to you [8D] I heard and have been told, "carry a spare fuel filter, each kind." Me being on my low budget, didn't, and never experienced any problems. My fuel filter was visibly clean when I bought it...If yours is dirty, carry a spare for sure, or have AAA PLUS. And in the winter time, don't run more than B45 I would say, in your tank at any time, because it gels, and will crystalize in your fuel filter and possibly cause damage. Otherwise, MAKE NO MISTAKE, BIODIESEL IS WORTH THE EXTRA $$$$$ AND PLEASE PUT IT IN YOUR DIESEL MERC NOW!!!!! KYOTO PROTOCOL ISN'T A BAD IDEA....RUDOLF DIESEL INVENTED HIS FIRST ENGINE TO RUN ON PEANUT OIL.
More expensive? Are you purchasing fuel or making it?

EDIT: Did you retard your injection timing like you are supposed to when running B100? Biodiesel runs hotter. BTW, if you have experienced a loss of power (how you have determined a horsepower number is beyond me) then you must have something wrong with your engine or fuel system. You should check your valve adjustment, injection timing, fuel filters, and fuel strainer screen. Biodiesel has more potential energy than petro diesel, therefore you should get more power and in turn better economy.
No, it has less energy and you don't get quite as good of fuel economy...Everyone I know that runs it says this. The manufacturer does too. I like your idea about whatever you said to make it run cooler...Could you elaborate on that? (I am spending the extra $$ to buy it retail, not making it yet...That is a goal of mine this year.)
Everything I have read from the journeytoforever website said that biodiesel will score about a 5% power increase. I did some extra research and found that the BTU rating on B100 is somewhere between no.1 and no.2 diesel. You are right, I have found more information supporting what you have said, the BTU rating of biodiesel is about 3.5% lower than that of no.2 diesel fuel. I wonder why I have found such conflicting information though. The thing I said about retarding your timing was that you need to retard your timing by 2-3 degrees in order to counter the higher cetane rating of biodiesel. Doing this will bring your engines operating temperature back to normal and reduce your NOX emissions, which are about 4% higher with biodiesel. Let me ask you this though, where are you buying B100 and what are you paying for it? According to the National Biodiesel Board, there are very few stations across the country that sell B100.
Steve, thanks for that tip on adjusting my timing...I need to do that for sure...I get my biodiesel at http://www.sqbiofuels.com/ It is a bit spendy, but I don't like those smog clouds in LA, San Fran, etc.
I have been messing around with biodiesel for about 5 years now and have used it off and on in my 87 300td. I have never had a problem with it. There is new federal legislation that brings its price down closer to #2 so it will start showing up in more places.
- It is a great solvent so be sure to wash it off any painted surfaces.
- It has a few less BTU than diesel but there is lots of urban legends saying it gives better mileage. I know of one large truck fleet operator that did carefully controlled tests with 5% and saw no difference.
- the high cetane is noticeable and gives the feel of a smoother running engine. (Cetane is sort of the opposite of Octane. Diesel combustion is best when fast. In gas, fast burn leads to knocking.)
- Biodiesel is the methyl ester as defined in the US and in Europe. Biodiesel is a lot bigger in Europe than here. Veg oil is triglyceride. I have no experience burning veg oil but plenty seem to do it. There is some concern about the glycerin in the veg oil coking up the works. Chemically, glyceirn is a little analagous to sugar.
- If you make biodiesel yourself, be careful to wash out the glycerin carefully. It is not very soluable in the fuel and messes up the filters - especially when cold.
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