Speaking of Biodiesel - PeachParts Mercedes-Benz Forum

john_rossi · #1 04-22-2003, 07:45 PM

We've now got a fuel station in town (Portland, OR) that is selling B20 and B100. I've been running B20 with no problems in my '85 300D Turbo. From what I've read, the only modifications required to run B100 are upgraded fuel lines & fuel filter replacement (due to B100 being a strong solvent). I'd like to hear from people who have done this 'conversion' and are running 100% biodiesel... any drawbacks? where can I buy the 'upgraded' rubber fuel lines (what do I ask for)? how long did it take to perform the fuel line replacement (difficult?)? any performance issues? anyone done a before & after emissions test?

Thanks for the help... I'm looking forward to reducing my non-renewable energy consumption!

-John

coachgeo · #2 04-22-2003, 10:54 PM

Ive been reading up on this for a long time, but have no practical experince as of yet. You can replace all your rubber lines with Pex lines. Do a search here to verify that Do a search here to verify that

Generaly, from what I have read is that the deteriation of the fuel lines takes quite a while. You are correct that you will super clean your engine. Prepare to change your fuel filter(s) almost weekly for a few times..... then every two weeks.. then...? till the filters stay clean.

coachgeo · #3 04-22-2003, 10:58 PM

the changes in emmisions is well researched and established studies show the decrease is SUBSTANTIAL For one.. there is no SULFUR (I think it's sulfer...... ) in veg. oil in the first place thus you cant have any of the related toxins to it...

just do a google search...... Biodiesel, Emmisions

TX76513 · #4 04-23-2003, 08:33 AM

I will probably be arrested by EPA shortly after pushing submit button sooo...... I actually add a sulfur additive to my older diesels. They were designed to burn the old fuel and power restoration is noticible to me. (For the Green People) Re-sulfering the fuel also reduces the noticible exhaust - I would assume this is from more "complete" combustion.

Fredmburgess · #5 04-23-2003, 10:10 AM

...well you knew I couldn't resist this one...! CoachGeo makes a good point about the lack of sulfur in biodiesel. No sulfur = no sulfer dioxide in the exhaust = no contribution to acid rain. The sulfur serves as a lubricant, which is good, and I can understand adding some to make current low sulfur fuels a better match for an older diesel. Vegetable oil and/or biodiesel are both better lubricating fuels, so one might just throw in a gallon of new vegetable oil as a lubricity additive...won't hurt, and might work just as well or better than sulfur.

Another great thing about bio diesel is that it doesn't put more carbon (as carbon dioxide) back into the environment. The carbon in fossil fuel is essentially out of circulation until we dig or pump it up and throw it into the air from our exhaust. Using bio-diesel or vegetable oil takes carbon that was already in circulation (in the recently grown plants) and puts it in the air where the same amount can be re-absorbed by new plants.

I know, blah blah blah, and I just wanna drive, too, but this stuff is really simple when you think about it. Alternative fuels have to happen, and we've all got a head start with our "old" engines!

...excuse me while I climb down off my soap box...!

coachgeo · #6 04-23-2003, 12:32 PM

From my meager understanding of all this Fredmburgess is correct. Many many state that once they switched to biofuels there cars improve dramatically when it comes to smoother idle and quieter running. The experts attribute this to the better lubricity of biofuels.

Second sulfer reduction in american diesel has been touched very little compared to european diesel. I dont hear squat from Europe about needing to imporve fuel lubricity of there older diesel rigs. Maybe Im not listening for it? Has anyone heard from europe bboards or friends if they are adding lubricants etc. to their fuel to replace the sulfer that is now of lower content in diesel fuels?

I also feel Fred is correct in that their are other products available now besides sulfer that are better for lubricity and better for the environment. Heck... just put a quart of off the shelf pure vegetable oil in your car. When you fill up. Im sure that is plenty extra lubricity compared to the sulfer reduction in diesel fuel.

coachgeo · #7 04-23-2003, 12:40 PM

Quote:

Originally posted by TX76513
I will probably be arrested by EPA shortly after pushing submit button sooo...... I actually add a sulfur additive to my older diesels. They were designed to burn the old fuel and power restoration is noticible to me. (For the Green People) Re-sulfering the fuel also reduces the noticible exhaust - I would assume this is from more "complete" combustion.

Does sulfer aid combustion? I doubt that. Im betting their is another explanation. Besides... black carbon smoke falls to the ground. Sulfer dioxide goes in the air unoticed and is far more coaustic to the environment.

#8 04-23-2003, 02:21 PM

Fredmburgess

"so one might just throw in a gallon of new vegetable oil as a lubricity additive...won't hurt, and might work just as well or better than sulfur"

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From what I've heard the Glycerin in the straight off the shelf vegetable oil will clog up the engine big time.

coachgeo · #9 04-23-2003, 11:02 PM

Quote:

Originally posted by 82-300td
Fredmburgess

"so one might just throw in a gallon of new vegetable oil as a lubricity additive...won't hurt, and might work just as well or better than sulfur"

--------------------
From what I've heard the Glycerin in the straight off the shelf vegetable oil will clog up the engine big time.

Im not an expert so I'll ask someone more expert than I and reply back here. Butttt that point does not seem to hold muster in my mind cause in Europe where diesel fuel prices are higher than Vegetable oil prices, this is done often. Again I'm no expert so I'll ask around.

coachgeo · #10 04-24-2003, 02:10 AM

so far the responce is no Glycerins but maybe some gums which I guess is not an issue when mixed. As I get more info I'll post here.

coachgeo · #11 04-24-2003, 10:22 PM

This pretty much answers the question about using FOOD GRADE vege oils for added lubrication to your diesel for reasons mentioned above (or other reasons)

Quote:

Raw Canola oil, freshly pressed, contains "gums" which are not suited as fuel components. They are also not suited as food, so are removed from most Canola oil sold as food grade oils.
De-gummed Canola oil is suitable as diesel fuel, providing suitable precautions and engine usage are considered.

This makes total since and Im sure it is the same for all vegetabley oils used for cooking (soy, peanut, etc.)

Fredmburgess · #12 04-26-2003, 11:06 PM

Well, all I can say is that used cooking oil (mostly soybean oil) is working pretty well for me (famous last words, eh?). I've got a heated tank in the trunk that I run on most of the time, also mix about 20% WVO in the diesel tank. I've only put about 20,000 miles on the car (now has 389,000) and don't know how much of that has been on WVO or a mix. I had a couple of the injectors out last month and they were very clean. Pre-chambers looked fine, too. This is just a rolling experiment for me but as I said, so far, so good. I'll let you know if anything goes "bang!"

Fred

LightMan · #13 04-27-2003, 08:23 PM

Boy the speculation sure goes crazy

Ok guys. First of all on the petro diesel fuel. Sulfur IS NOT a lubricant and does not provide lubricity. People started thinking this when low sulfur diesel came out and it had low lubricity. Its not the lack of the sulfur that causes the drop in lubricity, it's the process that removes the sulfur that also strips lubricity from it. Sulfur is what causes soot when burned and our current (500ppm limit) crappy quality diesel fuel is the reason we cant import a lot of cooler diesels, the high sulfur makes them fail emissions testing. Most of Europe burns ULSD(ultra low sulfur diesel) which is around 15ppm sulfur. Most of the US will be switching to this in 2006.

I've run b20 in my E300 for 2 years now, and have run b100 in my TDI for 20K miles. First of all , coachgeo is incorrect in his speculation about fuel filter changes. Sure, some folks that have a few hundred thousand miles and have a lot of gunk in their tank may have to change their fuel filter once if it clogs(although I've not heard of a single one yet, except from folks that homebrewed). Biodiesel is a great solvent, and has incredibly high lubricity. It also usually has a higher cetane number, which helps it burn more completely and quickly. The only downsides to b100 is that biodiesel has slightly less BTU's than normal diesel, so you will experience maybe a 5% mpg and power loss. It's worth it for the great smell, and smooth quiet performance.
If you're running an older vehicle, be prepared to upgrade your fuel lines. The best material to use that's compatible with biodiesel is Viton.

Last word of caution - be sure to wipe off any biodiesel you spill on painted surfaces, it will eat thru it, due to strong solvency. Also biodiesel is great to soak sooty parts in etc, for cleaning purposes.

For all you guys reading up on it and thinking about trying biodiesel, do it, you'll love the better smell, less smoke, quieter and smoother operation, and knowing some of your fuel dollars went to american farmers, not the middle east. Trying b20 is no risk whatsoever, and requires no mods. You will notice smoother and quieter running on b20 with about no power loss.

coachgeo · #14 04-27-2003, 09:15 PM

Thanks Lightman for the info about the lubricity being lower in diesel due to the “process” of removing sulfur and NOT the sulfur itself. With that bit of information then if you want to increase the lubricity of your low sulfur diesel it most definitely would be better to add some Food grade vegetable oil to your tank than it would be to add sulfur additive

As to how frequent you may have to change your fuel filters when you "first" go to B100, Just watch the clear prefilter and judge for yourself. Add one if you don’t have one. Like Lightman says the frequency of need to change filters may vary from, none to worst-case scenario where u may need too a lot. Again, this is only in the beginning stage of use, the older the car the more chance at higher frequency of changes will be needed.

LightMan · #15 04-27-2003, 09:21 PM

I would not say the filter change frequency would ever be a lot. I think most will not even have to change their filters earlier than their normal interval, but some may. That will likely be it.

As for adding straight vegetable oil to your tank for lubricity, I wouldn't recommend it, unless it's heated up before running(svo setups usually have a separate tank with a heating source). I'm not sure how cleanly it would burn or if it would even provide any benefit.

Use a diesel fuel additive designed for increasing lubricity, like stanadyne performance formula or lubricity formula, powerservice DFS or diesel kleen, or any number of additives. If lubricity is all you're after and you're not looking for a cetane boost, stability additives, etc that fuel additives provide, just add a little biodiesel. Biodiesel is not even close to dumping pure cooking oil in your tank.