The affects of Waste Vegetable oil on TDI's

AutoDiesel

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Beta

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Re: The affects of Waste Vegetable oil on TDI\'s

Depends on the temperature of the thermostat. Most open at 180-195. Engine temperature generally follows coolant temperature, duh. If ip is running hotter due to friction (scary) then 180 fuel would serve as a coolant. Either way 180 is a safe operating temp for anything attached to the engine.
 

McBrew

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Re: The affects of Waste Vegetable oil on TDI\'s

Even in Florida and similar climes wvo users blend in 5 - 10 % unleaded gas. This has reduces the viscosity a great deal. At least by half. And they do it in IDI engines in old M-B's and F-250's.
Hehe... two days ago, the tank of B100 in my 300D was getting low, and I knew I wouldn't be able to make it to Taylorsville to get it filled back up that day (80 miles), so I stopped by my friend's sushi restaurant and pumped 5 gallons of WVO out of one of his collection drums. I took it home and ran it through my 10 micron water block filter and into my fuel tank. That made it about 5 gallons B100 and 5 gallons WVO. Then I poured in about 1.5 gallons of kerosene I had left over from last winter.

It was about 75ºF the next morning when I started the car, and it didn't complain at all! The next day, I managed to get up to Taylorsville and fill up with B100... but for about 200 miles I was running an interesting blend.

Oh... don't do this at home (not in a TDI, at least). Those old MB diesels are bulletproof (even at 300k miles). The only thing I miss from my petro-diesel days was the cloud of smoke I could lay on some unsuspecting tailgater.
 

BioDiesel

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Re: The affects of Waste Vegetable oil on TDI\'s

DBW posted:
"Injection pumps that I have seen failed due to excessive wear on the pump cam plate rollers"

This may have actually been pitting, not wear.
Pitting is speculated to eb caused by micro implosions and explosions of tiny water droplets under pressure.
Similar to the cavitation problem in some diesels' coolant.
More info at Infopop

WVO should be de-watered so that no visible droplets pop when heated to 220*F+
Settling for a few days at ambient, or hetaing for a few hours to 160*F or , by spraying a fine mist through the air to allow the water in the wvo to evaporate.
Again, more info at infopop.
 

DuluthRooster

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Re: The affects of Waste Vegetable oil on TDI\'s

I am in the process of installing the TDI kit from Neoteric Biofuels (www.plantdrive.com) in my '02 Jetta Wagon. Donut tank fits right inside of existing full size spare so I dont lose use of the spare. WVO goes in Jetta tank, DinoDiesel in donut.

The kit utilizes a Vormax (also 5 microns) and Veg-Therm to heat oil to 158 degrees right before IP. car will start and stop on diesel from donut tank, whick I think is key.

I settle my WVO, then filter at 10 microns cold, then dewater and filter at 5 microns heated before filling car.

Call me crazy! stay tuned for results. I drive 40,000 miles a year so I will know soon enough. By the way my car has 50,000 miles on it
 

jsummer2

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Re: The affects of Waste Vegetable oil on TDI\'s

Hi, I have a 1998 Beetle TDI and contacted the same company about the Donut Tank kit that you are currently installing. If you have any pictures I would love to see them. Why did you decide on putting the VO in the donut tank. Regards, Joe.
 

DuluthRooster

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Re: The affects of Waste Vegetable oil on TDI\'s

I am putting diesel in the donut and it will only be used to start and stop the car. That way I am not starting a cold engine on WVO the next day. I will fill up the main Jetta tank with WVO. The system has a Pollak valve that allows me to switch between WVO and diesel from inside the car. This is the donut. It holds about 3 gallons of diesel:



 

latitude500

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Re: The affects of Waste Vegetable oil on TDI\'s

Are you really going to put it inside of the tire. You smart cookie you....

At least you know it wan't move around.
 

BioDiesel

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Re: The affects of Waste Vegetable oil on TDI\'s

An IP{ failure in a TDI w/Greasel conversion from infopop:

"I don't want to start a flame war here, but I've ended up installing a few Greasecar kits lately and have been really dissapointed with the design of the system, especially the inside-the-tank fittings. 3 fittings in the tank: 2 flare and 1 compression. 2 of the four kits leaked coolant. And there is no need for unreliable fittings to be IN a tank. An aquaintance just had to replace the IP on his TDI golf with 40K miles. The Greasecar kit has leaked coolant into the veggie twice over it's life.

Wanted to hear other's experiences with these kits before I stop installing them altogether. I am still recommending Neoteric's units, mostly due to the Veg therm, which I use on custom kits."

I class this failure as a c) type
"c) failures in the conversion process ( mis-wired , etc )"

The kit is either a poor design or improperly installed.
 

landshark

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Re: The affects of Waste Vegetable oil on TDI\'s

I installed my own greasecar system and I have not had any problems. I tightened the compression nut tight, as it is suppossed to be, and I have 3,000 miles trouble free. I am not a mechanic, all I have done previosly is change the oil and air filters myself. I can not tell the difference when I am running on WVO or diesel. There is not the "orange chicken" smell that I though that I would get either. I like the greasecar system. I called them several times while installing the system and they were great. Have you told them of the problem with the leaking? They will help you out. Hope this helps.
 

BioDiesel

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Re: The affects of Waste Vegetable oil on TDI\'s

landshark,

"Have you told them of the problem with the leaking? "

I'm just re-posting this from the infopop forum.
I hope the help amounts to $2k to replace the poor wvo'ers IP. But given the fittings could be easily mis-installed, I doubt it.

You should closely monitor your colant level and water separator.
 

DuluthRooster

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Re: The affects of Waste Vegetable oil on TDI\'s

I just completed the install of the TDI kit from Neoteric (http://www.plantdrive.com) in my '02 VW Jetta TDI Wagon. After researching much of what was out there in kits, I felt Neoteric would give me the best chance of success with the TDI. I had read many positive comments about components that Neoteric uses in their kits particularly the VegTherm and the Vormax. Heating the WVO properly and thoroughly along with this being a two tank system I believe is key with the newer TDIs.

This kit is expensive but the quality is top notch. The donut tank that fits into my spare (and allows me to keep the spare!) is a beautiful piece. Craig and Ed provided as much phone assistance as I needed and were very generous with their time.

Vormax mounts in engine compartment between the smaller Optima battery (I provided) and the engine. Vormax brackets are provided in the kit.
Pollak is on the front left mounted on a bracket
I fabricated from aluminum stock. VegTherm relay from the kit is mounted in the right rear of the engine compartment.


The diesel for starting and purging goes in the donut tank (3.5 gallons) fitted inside full sized spare:



I mounted Pollak switch in the cab using a blank in the dash:


I source my WVO from a local Thai place. They change their soybean oil weekly and put it in a barrel I provided. Soybean is not the very best oil but my source is clean, reliable, and contains NO water. They provide me 15 gallons a week which meets my demand exactly. I utilize Dana Linscott's filter/dewater setup where it is heated and filtered to 5 microns before going into the Jetta's main fuel tank. The Vormax filters it again to 5 microns.

Stay tuned for updates as the mileage accumulates and the fuel dollars are saved! (or a new injection pump per Drivbiwire!
)
 

NCTDIGuy

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Greenville NC
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2001 VW Golf Blue
Re: The affects of Waste Vegetable oil on TDI\'s

Don't do it DON"T DO IT!!!! TOO RISKY!!! My car is running like crap and it started shortly after installing greasecar kit. Don't do it to you TDI!!! DOn't do it!!! I am an example don't do it!!!
 

VWannabe

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Lawrenceville, GA USA
Re: The affects of Waste Vegetable oil on TDI\'s

DuluthRooster:

You should also check out this site
www.frybrid.com.
The quality of the kits he is making a top notch and the guy at Neoteric will be a distributor of his kits. I love that donut tank! Beware of the Pollak valves. If you read the Frybrid site, he is not using Pollak valves anymore due to failures he has had with them. You can buy the valves that he uses from his site and switch them out. Also, do you have a vacuum gauge installed? This is considered essential in determining if your VO is getting heated enough.

Where in Duluth are you? I live in Lawrenceville and work in Alpharetta, so I come right through Duluth every day. I would like to see your setup someday.
 

DuluthRooster

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Re: The affects of Waste Vegetable oil on TDI\'s

The Pollak valves that came with my Neoteric kit are motorized 6 port not solenoid. I believe Frybrid changed from the solenoid style Pollak 3 port valves. Solenoid valves can stick with cold WVO in them which is why Neoteric went away from them.

If I understand correctly, the Vormax has a vacuum gauge on it but it is not visible from the cockpit.
 

meetis

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Re: The affects of Waste Vegetable oil on TDI\'s

Here it is plain and simple from the first post I can't believe someone accually said veg oil is not a good lubricant. Funny as hell IMO how can anyone make such a statement. Ok if you really think veg oil isn't a good lubrican go ahaid and spill some on your driveway and try standing on it in seconds you will end up on your butt. I ahve had the extreme misfortune of haveing my full 30gal plastic barrel melting on me cleaning it up was a challenge just trying to not be on the floor. Veg oil at higher temps (ie 120+ where everyone that burns veg oil knows there temp should be) is a better lubricant then diesel without question it also flows better then diesel at higher temps. There is also NO proof that properly dewatered and filtered veg can cause IP problems. However if you do not take care to dewater your veg your IP WILL fail due to the water damadge. But thats due to the water not the veg oil. I run a greasecar kit myself no problems other then the ones I personally created.
 

GoFaster

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Re: The affects of Waste Vegetable oil on TDI\'s

It isn't enough for something to be a "good lubricant". It also has to possess the proper characteristics for whatever it is that you are lubricating.

Wheel bearing grease is a great lubricant for wheel bearings. It's not a great lubricant for the inside of an engine. Engine oil meeting the proper specification approvals is a great lubricant for the inside of an engine. It won't last long in a wheel bearing.

The fuel injection system on these vehicles was designed to be lubricated by diesel fuel meeting the appropriate specification approvals. Biodiesel approximates the characteristics of standard diesel fuel closely enough. Untreated vegetable oil doesn't; for one thing, it has considerably higher viscosity. Yes, you can raise its temperature to reduce the viscosity (although that's not the only important property of a lubricant), but consider the fluid properties at the injector tips themselves, where the temperature is a lot higher (and governed more by the running temperature of the engine than by the temperature of the fuel fed in). Is the slightly higher fuel feed temperature enough to bring the injection pressure into the normal range (so that the injector pump isn't overstressed) without causing chemical breakdown of the vegetable oil (which could clog nozzles)? I don't have enough information to answer this.

We simply don't know enough about the root causes of NC's problem to blame any one factor.

It may have been the vegetable oil that caused the problem. But others have used the same type of fuel without problems, so that can't be the only factor. It could have been an imminent failure. Whatever it was that failed, might have happened anyway regardless of the vegetable oil usage. (Injector pump failures have happened on regular diesel fuel.) It may have been something marginal, that the different fuel properties put "over the edge". It may have been impurities in the fuel that was used (water, contaminants, etc).

By the way ... if back pressure from the injectors is an issue (and WE DON'T KNOW if this is the cause of the failure!!), think "big injectors" ...

My own opinion is that straight vegetable oil differs too much from the properties of the fuel that the engine was designed to run on, for ME to consider using it.
 

DrStink

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Re: The affects of Waste Vegetable oil on TDI\'s

There is also NO proof that properly dewatered and filtered veg can cause IP problems.
Actually, there IS ample evidence that SVO can lead to problems with injector coking.

http://asae.frymulti.com/abstract.asp?aid=7474&t=2

An imaging system was used to compare injector coking when used vegetable oil from local grocery store deli fryers was used as a diesel fuel replacement in small proportions. Fuel blends containing from 2.5% to 20% used vegetable oil were studied to determine which oil fuel blend would be optimal for future engine testing. The 2.5% oil fuel blend had injector coking levels slightly more than that of diesel fuel, while higher blends tended to have significantly higher injector coking levels.
The leap from injector coking to IP failure really isn't that big a jump in my book. Two words: back pressure.

And according to http://www.uidaho.edu/bae/biodiesel/raw%20vegetable%20oils_literature%20review.doc
Bruwer et al. (1980) studied the use of sunflower seed oil as a renewable energy source. When operating tractors with 100% sunflower oil instead of diesel fuel, an 8% power loss occurred after 1000 hours of operation. The power loss was corrected by replacing the fuel injectors and injector pump. After 1300 hours of operation, the carbon deposits in the engine were reported to be equivalent to an engine fueled with 100% diesel except for the injector tips, which exhibited excessive carbon build-up.
Tahir et al. (1982) tested sunflower oil as a replacement for diesel fuel in agricultural tractors. Sunflower oil viscosity was 14% higher than diesel fuel at 37C. Engine performance using the sunflower oil was similar to that of diesel fuel, but with a slight decrease in fuel economy. Oxidation of the sunflower oil left heavy gum and wax deposits on test equipment, which could lead to engine failure.
Bacon et al. (1981) evaluated the use of several vegetable oils as potential fuel sources. Initial engine performance tests using vegetable oils were found to be acceptable, while noting that the use of these oils caused carbon build up in the combustion chamber. Continuous running of a diesel engine at part-load and mid-speeds was found to cause rapid carbon deposition rates on the injector tips. Short 2-hour tests were used to visually compare the effects of using different vegetable oils in place of diesel fuel. Although short-term engine test results were promising, Bacon recommended long-term engine testing to determine the overall effects of using vegetables oils as a fuel in diesel engines.
Schoedder (1981) used rapeseed oils as a diesel fuel replacement in Germany with mixed results. Short-term engine tests indicated rapeseed oil had similar energy outputs when compared to diesel fuel. Initial long-term engine tests showed that difficulties arose in engine operation after 100 hours due to deposits on piston rings, valves, and injectors. The investigators indicated that further long-term testing was needed to determine if these difficulties could be adverted.
Bettis et al. (1982) evaluated sunflower, safflower, and rapeseed oils were evaluated as possible sources for liquid fuels. The vegetable oils were found to contain 94% to 95% of the energy content of diesel fuel, and to be approximately 15 times as viscous. Short-term engine tests indicated that for the vegetable oils power output was nearly equivalent to that of diesel fuel, but long-term durability tests indicated severe problems due to carbonization of the combustion chamber.
Engler et al. (1983) found that engine performance tests using raw sunflower and cottonseed vegetable oils as alternative fuels gave poor results. Engine performance tests for processed vegetable oils produced results slightly better than similar tests for diesel fuel. However, carbon deposits and lubricating oil contamination problems were noted, indicating that these oils are acceptable only for short-term use as a fuel source.
Pryor et al. (1983) conducted short and long-term engine performance tests using 100% soybean oil in a small diesel engine. Short-term test results indicated the soybean performance was equivalent to that of diesel fuel. However, long-term engine testing was aborted due to power loss and carbon buildup on the injectors.
Likewise, according to Adam Khan's MS thesis:
http://www.cheque.uq.edu.au/ugrad/chee4001/CHEE400102/Adam_Khan_Thesis.pdf
Even after heating to around 80 deg C {canola oil} is still six times as viscous as diesel. This leads to problems with flow of oils from the fuel tank to the engine, blockages in filters and subsequent engine power losses. Even if preheating is used to lower the viscosity, difficulties may still be encountered with starting due to the temperatures required for oils to give off ignitable vapours. Further, engines can suffer coking and gumming which leads to sticking of piston rings due to multi-bonded compounds undergoing pyrolyses. Polyunsaturated fatty acids also undergo oxidation in storage causing gum formation and at high temperatures where complex oxidative and thermal polymerisation can occur.

To date there have been many problems found with using vegetable oils directly in diesel engines (especially in direct injection engines).

1. Coking and trumpet formation on the injectors to such an extent that fuel atomisation does not occur properly or is even prevented as a result of plugged orifices,
2. Carbon deposits,
3. Oil ring sticking,
4. Thickening and gelling of the lubricating oil as a result of contamination by vegetable oils, and
5. Lubricating problems.
In short, SVO is an EXPERIMENTAL FUEL with a history of problems with carbon buildup.

Can the problems surrounding SVO as a transportation fuel be solved? Maybe. Maybe not. Some people have had good luck with SVO systems while others haven't. But pretending 'everything is just peachy' does a disservice to the renewable fuels movement as a whole.

But why let any pesky old science get in the way of your true-believer "SVO is great" rant...
 

meetis

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Re: The affects of Waste Vegetable oil on TDI\'s

I see one problem here you are assuming that people run cars on veg oil all the time. Most run on diesel or bio-d to warm the engine up to temperature and get the system ready. Many people using veg oil use thermostats to monitor the temp of fuel going into the injector and dont switch over untill it is over 150f (I dont have a clue what 80c is) I have read my share of studies all of them point out veg oil being more fluid then diesel once it is up to 160. or higher temp no idea where you find info saying contrary. Diesel also gives off very little "fumes" for ignition remember this is diesel not gas. From your post i can easily see you have not read any of the general precautions all good greasers follow. There are a select few people even i think are crazy because they do not "purge" there system In general tho people that use WVO purge there fuel system this is done with a simple switch and valve the fuel lines go back to diesel and the return diesel line is routed to push veg oil back into the veg tank therefore diesel is in the filter and when the car shuts off there is diesel waiting for when the car is fired up> (dam filterkeys dont like to shut off) veg oil is considered experimental but if you do some reading and understand how to prevent certain things from happening there is much less risk remember also there are people out there that have run there cars on veg for one hundred thousand and more miles with no seriouse issues
 

GoFaster

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Re: The affects of Waste Vegetable oil on TDI\'s

80 degrees C is 176 degrees F ...

It is apparent from the above excerpts that different types of vegetable oil have widely differing viscosities. For example, sunflower 14% more viscous than diesel (no big deal), but rapeseed/canola oil is 6 times higher than diesel even when heated to 80 degrees C.

Those studies from the early 1980's were not necessarily done using fuel injection systems comparable to the TDI. Higher injection pressures put more stress on all the components, and smaller injector orifices are used.

More current research using modern high-pressure common-rail or pumpe-duse would be appropriate. It would be interesting for one of the folks with high mileage on vegetable oil to pull their injectors out and have them inspected with a microscope, or even just have the spray patterns checked.

Keep in mind that driving patterns may have an effect, too. Back pressure on the injector pump depends not only on fuel viscosity but also on engine RPM. The temperature at the injector nozzle tips depends on how much load the engine sees. This would suggest that a slow, gentle driver might not have this problem, but someone who uses the revs and the pedal might.
 

MiksTDI

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Re: The affects of Waste Vegetable oil on TDI\'s

Your first comparison didn't talk about heating the vegi oil before injection. The testors simply replaced the diesel with this soy and sunflower oil etc. and ran their engines. The progress with all companies has been the 2 tank system. Basically, heat the piss out of it before you hit the switch.

I drive 45k miles per year and have 202k curently on my Jetta with the Greasecar setup. I have temp gauges to monitor almost everyhing. My nozzles were replaced (Upgraded) at 150k due to my own power hungry right foot. That might help too, don't know. The old nozels were just fine I was just told to replace them every 75k by someone(can't remember who but telling it to the wife allows you to make a wearable item buy
, like new wiper blades
Especially when you tell her you made them last twice the life expectancy of normal nozzles). Anyway, I run the crap out of it all the time! Speeds up to 125 in the mornings and toting my Quad around too. I don't baby my baby. I drive it like I stole it.
I work in Chicago, Indiana, Michigan, Tennessee, Iowa, Minnesota and Wisconsin. I live in Kenosha, Wisconsin. It's a bit nipply here in the winter so it's best to watch the temp rise before you hit the switch....
 

DrStink

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Re: The affects of Waste Vegetable oil on TDI\'s

I see one problem here you are assuming that people run cars on veg oil all the time.
I assume no such thing. I simply pointed to 7 different reports on coking will using SVO.

Most run on diesel or bio-d to warm the engine up to temperature and get the system ready. Many people using veg oil use thermostats to monitor the temp of fuel going into the injector and dont switch over untill it is over 150f
Of this I am quite aware. I've spoken at length with Jim Burke about his success with SVO in his Mk3 Jetta.

This doesn't change the fact that SVO is an experimental fuel one bit.

(I dont have a clue what 80c is) I have read my share of studies all of them point out veg oil being more fluid then diesel once it is up to 160 or higher temp.
As noted above 80C is 176F, well in excess of 160F. Do you have source for these "studies" or am I to take your word for it?

no idea where you find info saying contrary.
Umm. Here
http://www.uidaho.edu/bae/biodiesel/raw%20vegetable%20oils_literature%20review.doc
and here
http://www.cheque.uq.edu.au/ugrad/chee4001/CHEE400102/Adam_Khan_Thesis.pdf

Did I stutter?

Diesel also gives off very little "fumes" for ignition remember this is diesel not gas.
Huh? What does this have to do with anything being discussed here?

From your post i can easily see you have not read any of the general precautions all good greasers follow. There are a select few people even i think are crazy because they do not "purge" there system In general tho people that use WVO purge there fuel system this is done with a simple switch and valve the fuel lines go back to diesel and the return diesel line is routed to push veg oil back into the veg tank therefore diesel is in the filter and when the car shuts off there is diesel waiting for when the car is fired up> (dam filterkeys dont like to shut off) veg oil is considered experimental but if you do some reading and understand how to prevent certain things from happening there is much less risk remember also there are people out there that have run there cars on veg for one hundred thousand and more miles with no seriouse issues
Actually, I am quite aware of how two-tank setups work. I am also aware that some people have had great success with SVO. If you one of those people, congrats!

However, I think you shold also be willing to step back from your emotional investment and discuss both the pros and the cons of SVO objectively.

I wasn't attacking SVO. I was just pointing out that SVO does have known problems and that pretending that problems don't exist doesn't help anyone. Moreover, I provided links so that people could follow up if they so chose.

In particular, I took exception to the implication that anyone that has problems with SVO is to blame because they failed to use properly dewatered and filtered SVO. You can do everything right with SVO and still have issues, that's just the nature of the beast.
 

latitude500

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Re: The affects of Waste Vegetable oil on TDI\'s

I installed my greasecar kit last march, and I wasn't waiting long enough to switch over to veggie, and I did notice that my new nozzles where getting nasty looking, but it didn't do anything for performance, I just have to wait a little longer to switch over.

Kits works great.
 

Vegi_VW

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Re: The affects of Waste Vegetable oil on TDI\'s

... I think you shold also be willing to step back from your emotional investment and discuss both the pros and the cons of SVO objectively.


I wasn't attacking SVO. I was just pointing out that SVO does have known problems and that pretending that problems don't exist doesn't help anyone. Moreover, I provided links so that people could follow up if they so chose.


In particular, I took exception to the implication that anyone that has problems with SVO is to blame because they failed to use properly dewatered and filtered SVO. You can do everything right with SVO and still have issues, that's just the nature of the beast.
Dr. Stink, I think you and I agree on this, but we're coming from different sides of the fence. You CAN do everything right with SVO and still have issues. However, you can do everything right with diesel and still have the same issues (failed IP, coked injectors, etc.)

So, how do you determine what failure rates are normal, and what aren't? You do research. I haven't read every single one of the studies in the material you cite, but I have read many of them. Most of them are from the 1980s, when the need for preheated fuel wasn't quite as well understood as it is now. Additionally, most engines tested in those early studies had flat-topped pistons (no TDIs with their swirl-cup piston, rumored to be based on an Elsbett design.) For example, even the most recent study cited in the Jones and Peterson review (McDonnell et al. 2000) is unclear on whether or not the fuel was heated -- they chose to test a 25% VO blend because that was as much VO as they could use while maintaining a sufficiently low viscosity at -12C (that's 10F for those of you who are metrically-challenged.) In addition the oil they used was "partially degummed" -- the food-grade SVO/WVO that most people use have had those gums completely removed. That's sort of like saying engine won't run on diesel that's been chilled to -50F with a little bit of sticky stuff thrown in. Should we then conclude that it's impossible to run an engine on diesel, period?

My point is not that all of those studies are worthless -- I'm glad they were done. My point is rather that the research I have seen is not representative of how most people run VO in their TDIs. Until we get some, the jury is still out.

Now, I would LOVE to see some more current research, either lab engine tests or (preferably) real-world comparisons between cars running VO and diesel. But that costs money. Perhaps now that the current administration has made a public commitment to biofuels, funds will become available for testing these sorts of things.

You're saying SVO is experimental. I agree with you completely. You say problems happen with SVO. I agree, but with the caveat that nobody really knows how much more often these problems occur on VO vs. diesel. You say to drop the emotional investment in SVO and discuss its pros and cons rationally. I agree -- SO LONG AS those who have an emotional investment in deriding SVO do the same.

I don't like it when SVO promoters act as if the issue is closed, and that VO is proven safe. But I take exception also to the implication that anyone that has problems with SVO is to blame simply because they used SVO.

There are plenty of anecdotes on both sides, but precious little appropriate data. Until we get some, can we discuss this like rational adults?
 

Mike_M

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Re: The affects of Waste Vegetable oil on TDI\'s

I installed my greasecar kit last march, and I wasn't waiting long enough to switch over to veggie, and I did notice that my new nozzles where getting nasty looking, but it didn't do anything for performance, I just have to wait a little longer to switch over.

Kits works great.
One year wouldn't be long enough for the type of long-term damage to occur that I believe is being discussed. How do the nozzles look now?

Mike
 

BioDiesel

Veteran Member
Joined
Oct 29, 2001
Location
CT
TDI
'98 Jetta
Re: The affects of Waste Vegetable oil on TDI\'s

Hey DrStink,

We're friends, but I have to point out that most of the research cited is outdated and doesn't reflect current SVO systems.

"Bruwer et al. (1980)... (1983)...(1982)"

"..difficulties may.."
"To date there have been many problems found with using vegetable oils directly in diesel engines (especially in direct injection engines)."

I don't even need to research this statement to know it's circa 80's. And only applicable to early industrial DI engines.

But thanks for posting and at least scareing the noob's out there enough to do more investigating.

Jim
 

BioDiesel

Veteran Member
Joined
Oct 29, 2001
Location
CT
TDI
'98 Jetta
Re: The affects of Waste Vegetable oil on TDI\'s

"More current research using modern high-pressure common-rail or pumpe-duse would be appropriate. It would be interesting for one of the folks with high mileage on vegetable oil to pull their injectors out and have them inspected with a microscope, or even just have the spray patterns checked."

Many have and have posted pics, although I don't have bookmarks. Results differ depending on engine design and condition. Many state they look like dzl fueled inj's with the same mileage on them.

Anyone remember the B100 fueled Yanmar inj. pics posted here?
Some engines don't have the necessary design features. But A VW TDI that goes 200,000 on SVO proves it's not one of them.
 
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