ShirazAddict

Anyone out there know of anyone who has done this conversion to their GL 320/350? Met a guy this AM who just converted his (older) Ford pickup 2 months ago, and he says he is saving almost $500 per month on fuel charges. It cost him $700 for the conversion kit/time, but almost an immediate payback (outside of the time spent collecting/sourcing/filtering used veggie oil).

I have a GL320 Blutec that still has almost 2 years on the factory warranty---while I'm not going to pull the trigger on this conversion tomorrow, I might in 2 years when the warranty runs out (assuming I could find a warranty from an aftermarket co that will allow such a conversion, even if it meant that the engine wasn't covered).

Saving $5-6k per year on fuel is really appealing, especially over an anticipated 5-8 year ownership period.

Thoughts?

Fourdiesel

The pizeoelectric injectors on your 350 Blutec are light years ahead, technology wise from the Ford Powerstroke your neighbor uses veggie oil in. The one word answer is DON'T! if you want to save money, you won't! The replacement/ installation costs of new injectors, fuel high pressure pump (price one of those babies out!) and other components FAR exceeds the savings. Veggie oil WILL get through unburned and plug up the emission components and they will have to be replaced also.
The big issue is that the fuel related parts of your Benz are NOT designed to handle the viscosity and properties of used (or new) veggie oil. The technology just isn't up to making the emissions work with veggie oil. And if the emissions don't work, putting the vehicle back in the shop to make them work is SPENDY! IT JUST WON'T PAY.
Live in a state or city where routine inspections are required for licensing? The situation is worse!

Brocktoon

Oh Kent, where are you? Come out, Come out, wherever you are...

mdadgar

Shhhhh! We're hunting wabbits ...

- Mark

lkchris

Fourdiesel has said it perfectly.

My only addition would be to implore the original poster to post his VIN number so the rest of the world can avoid his vehicle when it comes time he wants to sell it. Seems to me that's the ultimate religious testament in this regard.

MB7

I have operated my 2007 Mercedes GL320 CDI on 100% biodiesel in summer and 20-50% biodiesel in winter for the past five years. I have the fuel filter changed once per year in the spring to avoid clogging. The engine runs smoother and cleaner with biodiesel. The engine currently has more than 79,000 miles. No modifications were necessary to operate on biodiesel. We use biodiesel made from recycled vegetable oil available from many suppliers. Our favorite supplier is Bentley Biofuels see http://www.bentlybiofuels.com/. We also use B20 biodiesel from Shell and Rotten Robbie. Mercedes Benz specifies only using 5% biodiesel. Using B20 to B100 has had no negative impacts on our engine or catalytic converter.

giffie

Many of you might be surprised... but here in the Midwest (Champaign/Urbana), the DEALER fills up all new diesels with 5-20% Bio Diesel blend!

I asked the dealer about warranty issues when he himself is filling up with 5%-20% Bio Diesel blend... he said that he is not aware of any warranty issues and that I should not worry..

But I always fill up my diesel with non-bio, premium diesel. There is only ONE pump in whole of Champaign/Urbana that carries 'fossil' diesel (Meijer store on Philo Rd)

Fourdiesel

I don't suppose there has been any occasion to take the hp fuel pump apart to determine if there is more than normal wear. Thus there is still an open question about negative impacts. Pumps/injectors are designed for very specific viscosity and lube properties. Bio doesn't meet those parameters - even if clean.
Not to say it won't work in your case, but given the expense of a new hp pump it could be a very expensive experiment. A lot more risk than I would take. And typically bio costs more (at least here) than plain old #2 dino anyway and it doesn't have the heating value so mpgs are always less. Lots of risk, minimal advantage.

IridiumRoad

The Mercedes vehicles sold in the USA with DPFs (Diesel Particulate Filters) are incapable of running high percentages of biodiesel. That's any US-spec Mercedes diesel from model year 2007 onward.

If you want to understand why, you can do some reading online about the "biodiesel post-injection problem". Here are some articles:

http://www.biodieselmagazine.com/art...ction-problem/

http://www.popularmechanics.com/cars...ofuels/4311498

http://savebiodiesel.com/detail.html

The gist of it is that biodiesel doesn't vaporize or burn at the same temperatures as dino diesel, and the result is "oil dilution." The biodiesel accumulates in the engine oil instead of vaporizing during the post-injection process, and burning during the DPF cleaning cycle. Eventually this will dilute the engine oil and you'll get a CEL -- and you won't be able to pass an emissions test with the CEL set, if your local area has one. That's in addition to damage to the engine that may occur, as noted by prior posters.

So no, you can't run 100% biodiesel in a GL320 or GL350 -- at least not for long.

Gersh320

We just got a 2012 ML350BTC in the shop today. Lady filled with Diesel near the IL border (now using B20 in entire state!!!). I had a feeling some of that fuel is being used to fill pumps in St. Louis. Sure enough, it was about 18% biodiesel. Check engine light on, poor performance, rough idle. YES it WILL void warranty if B20 is used.

a2j

Filling up with used cooking oil and B10 is not the same thing. I filled up with B10 once and have not notice any difference in performance or MPGs. Price was a little lower.

alx

This. In so many words.