Hi Anyone
I'm still trying to get solid data from people (preferably several) that have first hand info with running B100 in the in-line 6 cyl, 2004 - 2006 era Mercedes 320 CDI engines. Many conflicting reports on the www, but I suspect these common rail engines are ok with it. Please anyone care to throw in their 2 cents or know someone that has experience?
Thanks. PD

i would choose a different vehicle if you are planning on running homebrew (unless you are pretty confident in the quality of your product).

But if you are getting it from the pump it should be fine at blends b20 or below, b50 is prob the highest you want to go. I know someone that has been running bio on a 2005 or 2006 for at least 2 years, don't know the blend ratio but he claims it takes b100 fine...I think he usually runs between b20 and b50 though. If you are in cold weather i wouldn't go higher than b50.

If you are concerned about the cost of problems then I would say get a cheaper diesel vehicle.

PD:
Really inerested in your findings.
Please keep us posted.
Thanks
Tom

No direct experience, other than knowing a guy that ran a late-model 320CDI on commercial biodiesel. He had no problems that I know of. That said, don't let the common rail and injector and engine-cost naysayers turn you off of trying it if you're willing. Focus instead on the exhaust components, which really cause most of the biodiesel issues in recent models. Was M-B already installing DPFs as early as '05? I don't think they were required until after that, so you might have one of the last cars without the biodiesel-related emissions issues. I'll not lecture you on all that, as I trust you know about lube oil dilution and so on.

I ran some commercial biodiesel as well as a ton of homebrew in my Volkswagen V10TDI (more complex and far more expensive engine) for a few years with nary an ill effect. I intentionally bought an '04 model for biodiesel purposes, as that year did not have DPF, or urea injection, or any of the stuff that has made modern life harder for biodieselers.

I say go for it! Good luck and keep us posted.

Cheers, John

PD, think you hit me up on over on the MB forum, if so it's a repeat.

I also own a 05 CDI, mine just rolled over 113k miles and now running it on biodiesl blends. So far I've worked up to B40 without any issues. Just changed the first fuel filter since I purchased it and all looked fine. MB specifically states "No biodiesel blends over B5" which is due to the Bosch common rail fuel system. Not to say they are wrong, but I feel its a CYA thing prompting that call.

The biggest known problem is fuel oxidation due to the heat and pressure in the rail, common fuel temps are 120F or so. The returned fuel gets sprayed back into the tank hot, mixed with air and then pumped back to the rail again. Second is fuel rail pressure, 25,000PSI at WOT. Those pressures have been known to cause some unexpected reactions in less than perfect biodiesel. Any moisture gets busted out into water droplets, dissolved solids, soaps, and free glycerin can be separated from the fuel and so on. All that can lead to deposits in the injector bodies, which just happen to be rated at 2 micron tolerance. On this year CDI there is no exhaust DPF, just the variable geometry turbo same as Ford and everyone else is using. Least of your worries..

So it basically comes down to how well ya trust your fuel, and if your able to work on things yourself. Because if ya do have issues and take it in for service, the MB dealer is gonna bend ya over the hood and have his way with ya... If your into cars and like to work on things yourself, it's actually a very easy well designed fuel system, just a bit pricy. I hosed up the injectors on my common rail Duramax and was able to disassemble and clean them vs spending 3K to replace. The CP3 pump is rock solid, the injectors bodies are where you'll get burned if something happens.

So there ya go, tread lightly and I'd go 50/50 max for a few months then inspect for deposits in the rail area. When I reach B100, I'll be sure to let ya know. Maybe some of the Dodge or Chevy common rail guys want to chime in since it's all the exact same Bosch parts we are using.

-K

If you're not confident doing your own repairs, as Kenr is, find out how much it will cost to fix your system should something go wrong.

If ya still have warranty time left, here is the official MB service bulletin on the subject.

-

Diesel Fuel System - Incorrect Type Of Fuel Filled

Date: September 12, 2006
Order No.: P-B-47.10/30b
Supersedes: P-B-47.10/30a dated Sept. 2, 2004
Group: 47

Revision History

Revision Date Purpose

b 9/12/06 Applicable Model / Step 3 and Parts Information Updated
a 9/2/04 Additional Information Pertaining to Biodiesel Fuel
- 8/17/04 Initial issue

SUBJECT:
Model 211.026

Procedure for When Diesel Fuel Tank is Filled with Incorrect Type Fuel

If the above model diesel powered vehicle with a common rail injection system has been refueled with gasoline, kerosene, etc. and/or other mixtures thereof, follow the steps below to remedy. In addition, biodiesel fuel (B20, B100) or any mixture thereof is not permitted for use in the above model vehicle.

Please note that should the customer fill the fuel tank with the wrong type of fuel this may not be submitted as a warrantable claim.

------

Food for thought, a single injector retails for $440.00

-K

Great info from someone that's actually running the vehicle/fuel -- awesome! I do have a soft spot for those inline-six engines. So smooth.

quote:

Originally posted by Kenr34:
Please note that should the customer fill the fuel tank with the wrong type of fuel this may not be submitted as a warrantable claim.

Assuming biodiesel (or a blend over B5) is the "wrong type of fuel," this over-broad summary nonsense is exactly why we have the Magnuson-Moss Warranty Act. I've lost count of how many dealers I have backed down from "non-warranty issues" when I bring that one up. They just know that 99 out of 100 people aren't going to challenge them. Huh...does that make me the 1%?

Cheers, John

My Jeep liberty had a bosch CR system. It has piezo injectors and the bosch CP3 pump. I don't know if they are the same as the MB or not. Libby runs fine on 100%. Done over 20K mi now on B100 homebrew.
Also have older E300, 1999 W210 chassis. Works fine but a much different fuel system.
Also have VW Passat with PD. Has even higher pressure than the your MB. No problem with 100% bio. But no CP3 pump like the libby or benz. The VW experience lines up with the guy running a V10TDI.

I want to purchase a newer MB like yours with the inline 6 motor but have the same reservations. I haven't seen definitive answers on running B100 in this car. I do hear that the V6 engine has some metal in the fuel pump that will fail with bio.

I'll keep looking to find someone who has difinitive results and report back if I do. If you find anyone also please report back.

Believe the Jeep Liberty and 05 E320 CDI share the exact same CP3 pump. So that provides us a bigger pool of data to consider. Many of the small parts like pressure regulator and most sensors are interchangeable across the board of engine manufactures.

When I was considering this CDI purchase, the inline 3.2L was the deciding factor over a newer V6 3.2L model. Ease of maintenance on the straight six did it, everything besides the turbo is just right up front or on top of this engine.

So not to highjack this thread, I posted a great common rail injector video and details of my personal experience "what not to do" with B100 and this fuel system over here.

http://biodiesel.infopop.cc/ev...4104603/m/1447069943

-Ken

I have an 06' E320 CDI. It came with 50K on petro. It now has an additional 20k on B100.
It runs smooth and quiet with no issues so far. Blends of B50-B20 in winter. No filter change as yet,
and I must brag my fuel is crystal clear. It's my wife's car, so it better not shut down, or my a@@ will need a rebuild.

quote:

Believe the Jeep Liberty and 05 E320 CDI share the exact same CP3 pump. So that provides us a bigger pool of data to consider. Many of the small parts like pressure regulator and most sensors are interchangeable across the board of engine manufactures.

Seeing first hand how the Auto industry takes advantage of the " Economies of scale "
The above statement is no surprise. With that in mind I believe Daimler builds the same motor for the US and European markets. Biodiesel is and has been available in Europe for some years now.
It seems logical to me that the fuel systems would be Biodiesel tolerant?
I'm in the market for a diesel Benz. have been looking at the older CD coupes for the same reasons
this discussion is underway. Any MB Mechanics out there ,,, feel free to Chime in !!!
regards to all

Tom

Ken34,
Absolutely AWESOME write up in that other thread (as to be expected).
Great great stuff!

Also, I have a customer that's reported back that they've been running B100 with success in an 05 E320 (about 40K). They don't ever have "old fuel" in the tank, so they don't experience the degradation issue that Ken34 discussed, but it's definitely something to consider (ie. keep fresh fuel in the tank or flush with diesel if you're going to store it for long periods).

-Graydon

Thanks Graydon.

Think we all need to better understand and respect the properties of finished biodiesel, especially in these new close tolerance fuel systems. Everyone is so focused on making the best quality fuel, we often forget things don't always stop once it's in the finished tank. My issues was defiantly uncommon.. Sealed tight it's rare to have those fuel oxidation problems, however exposing to air, sunlight, or heat can all degrade pure biodiesel much faster than we'd expect.

The common rail system introduces two of these degrading factors by it's design. Unused fuel is returned to the tank HOT and sprayed out into the open air space under pressure. Think of it as air drying fuel to extremes. IF ya fill up and burn all the fuel quickly you're beating the oxidation clock. Short drives with long periods parked is where I could see problems developing. Cutting the bio blends back in those situations should work to your advantage.

I'm still stuck at B40 today cause of outside temps, but at this level no mileage impact in our CDI. In love with this engines performance so far, if I could only get it to roll coal. LOL



-Ken

Ken, are you sure that thing is set for U.S. gallons and not imperial gallons? That's insane fuel economy! My old W210 chassis E-class never reached that far above 30mpg. I could achieve 33-34 if I took it really easy on flat terrain, but I sure never saw 37mpg. (Of course, we're talking about a car with 200k+ on the clock, too.)

Wow, that's just awesome for a very modern luxury sedan.

Cheers, John

quote:

Originally posted by dukegrad98:
Ken, are you sure that thing is set for U.S. gallons and not imperial gallons?

Yeah that's in US gallons, B30 blend, 14 miles of flat road and cruise set at 65mph. Best to date is 38.5 on a warmer day.

Long term average shows 29.8 over past 320 miles, slightly better than EPA listed "27 Combined" for this model.

PD and Paul, what's your CDI averaging ??

-Ken

38.5mpg is outstanding.
What method are you using to show that your mpg is 38.5 over 14 miles. Is it both ways?

Jacobh,

purely sharing the mpg calculated by the PCM at this point. Currently been adjusting fuel blends based on the 3 day weather forecast, so haven't topped off a tank. Also recently replaced a faulty thermostat that was hurting mileage with low engine temps.

In a few weeks we're taking a 1600 mile road trip, will start out on B30-40 first tank then fill up with petro-D to verify. I'll check actual vs estimated and bio blended vs straight over 800 miles each way.

-Ken

PD and Paul, what's your CDI averaging ??

my wife drives mostly in city traffic, so that hurts the average,@ 26 mpg.
on the road, however, it really shines, as much as 37 mpg depending on conditions/blends.
it's a great car.

PD here. I do not own a CDI, I've been considering acquiring one, thats why the questions. And thanks to all that have volunteered good data here.
On the issue on fuel oxidization as Kenr suggests ... I ask if this were such a big issue why wouldn't more engines have oxidization related problem as all diesel vehicles have fuel returned to the tank in similar conditions? I believe some / many motor manufacturers actually rely on the fuel flowing thru the fuel system & injectors to carry out a portion of the engine cooling. Therefore one would presume the return fuel likely carries quite a bit of heat.

BTW, To date I've spoken directly to the fellow Graydon refers to, both he & his bro run B100 in their CDIs without major issues, & I've spoken w/ a fellow in Calif that does the same w/ no major issues. Its starting to sound like B100 is compatible in these engines.

Thanks to all that have contributed to this thread, lets see if we can keep it going. All this data is particularly significant these being the last engines Mercedes produced that are B100 compatible.
PD