Passat 2005 Running On Used Soy Oil And B100

Hi Kevin - I am a mechanical engineer who lives in Upstate NY, and I am very interested in purchasing a used diesel vehicle this summer and converting it using a greasecar kit. You are probably familiar with their dual tank concept that keeps the stock fuel delivery system and the veggie oil is used "mid-trip" while regular diesel is used for start-up and shutdown. I find the idea of doing this fascinating, but worry about the cold weather aspects that I will be dealing with many months of the year. At this point, I am educating myself, and I have found your blog fantastic. I admire your courage for jumping in, and have found all you have learned and shared as being invaluable. Your sense of humor makes it even more fun to read. In trying to decide what used vehicle I will perfom my "experiment" on I came across a list published by Culver's restaurant. (They are currently pushing a promotion for all of their franchise owners to convert a car and then advertise on it.) The list had this caveat which I will cut and paste here: "The Volkswagen TDI vehicles introduced new engineering in late 2004 that is less adaptive to vegetable oil conversion." I wish they went into more detail than this, but hopefully less adaptive is minor in nature, and does not apply to your car. If I find anything else out, I will let you know. Please keep up your posting, I am looking forward to your continued effort and I applaud everything you are doing!!
 

Kevin, I too have come to the conclusion that the oil in the doughnut tank can not be good over and extended period of time. I've finally come to the conclusion that I plan on flushing the doughnut tank every other tankful.

Basically I dump the contents of the doughnut into the veggiue tank and refill the doughnut with fresh diesel.

I want to install the 2- 3port vales that you mention but the downside is that it will deplete the doughnut tank that much earlier.
 

The list had this caveat which I will cut and paste here: "The Volkswagen TDI vehicles introduced new engineering in late 2004 that is less adaptive to vegetable oil conversion."

I think the Direct Injection system has a much higher compression ratio, making the the WVO much more difficult vaporize.
 

From what I can recall the studies involving SVO found that improper atomization resulted in a flame front that caused erosion of the cylinder walls. It appears that your iron levels jumped almost as soon as you started using veggie oil which seems to indicate that the newer PD diesels are ill suited to this conversion.

UNLESS of course you figure out a way to inject the oil with precisely the same pattern. This requires getting the oil way hotter than most kits manage. You'd have to make viscosity equal to diesel or probably a far more practical approach, to use an Elsbett injector setup.

I too have read your blog with fascination and admire your efforts. From your approach we can deduce that most of these VO conversions are simply too poorly engineered to perform with modern diesels. This ain't no IDI mercedes we're fooling with! The proper course seems to use even higher oil temps and modded injector spray. Also using new VO vs. WVO... used product is simply too much of a crapshoot if you value longevity.

I also question the validity of "saving the planet" when many of the conversions are running on sootbelching ancient tech vehicles. Sorry but a Prius leaves a much smaller environmental footprint! Run it on E85 if you're bio-fuel crazy.
 

Veggie Oil conversion cost $2,000, wasted turbo charger from sloppy mechanic, $2,000, wasted unit injector pump, 4 new nozzles, and flush the tank, lift pump, tandem pump, cylinder head and fuel channels, $5000. Needing a new motor due to iron wear and stuck rings from glycerine in WVO, $10,000.

Reading this blog on failure after failure after failure on WVO in a Pumpe Duse motor? PRICELESS!

And just how much have you saved on fuel bills and how much more land fill have you created by this car ending up in the dump?