This is from another forum - Just a little FYI

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This is taken from the new pages at Greasel.com

I've heard that that there are problems associated with running SVO
in direct injection engines, is this true?
The short answer is no, for the long answer, read on:

TDI verses IDI

There've been a lot of questions, and misinformation regarding the
suitability of the direct injection engine to burn straight vegetable
oil. Here is some information that will help you make up your mind
for yourself.

The indirect injection diesel uses a pre-combustion chamber that
is connected to the main space above the piston by a narrow passage
way. When the fuel is injected into the chamber, there is not enough
oxygen for complete combustion, but enough combustion happens to
raise the pressure of the chamber to cause the fuel air mixture to
rush out through the narrow passage into the main area above the
piston. This rushing out through the passage completes the mixing and
atomizing of the fuel /air mixture, where it completes its burn.

This type of engine is tried and true when it comes to burning
vegetable oil.

The Direct injection Diesel takes a different approach to mixing
the fuel with the air. The chamber is designed to energize the air.
The two things used are swirl, and squish. The angle of the intake
seats causes the air to swirl as it enters the chamber. The edges of
the piston crown parallel to the chamber roof, when the piston gets
close to TDC the air gets squished between these two faces to the
center of the chamber. The fuel is injected directly into the main
chamber above the piston, into this turbulent air, and is mixed and
burned.

Direct injection Engines with high pressure unit injectors
(20,000- plus PSI) make the fuel an active element in the mixing
process. A Detroit diesel is a good example.

The most common fear sited, is that running a DI diesel on veggie
oil will cause injector coking. Injector coking is the build up of
carbon, due to incompletely burned fuel. This causes the spray
pattern of the injectors to deteriorate, causing more unburned fuel,
and the problem gets worse in a real hurry.

If there was a problem with injector coking it is more than
likely that the problem would manifest itself within the first 1,000
miles or so, and get progressively worse. The symptoms of coked
injectors are, Hard starting, excessive smoke, drastic drop in fuel
economy, and substantial loss of power. Of all of the engines we have
converted, Indirect injection and Direct injection, there has never
been a problem with injector coking. Furthermore, I have never
been presented with any evidence that would lead me to believe that
it is a problem. When I hear someone say that a DI run on SVO will
have problems, I ask them where they got there information, and if
there is any proof. To date, nobody has ever produced an engine that
had these problems. The closest I get to fact is, that some
university ran a generator on unheated SVO for 25 hours and had
injector coking.

On the other hand, we have converted more than a few DI engines
that have over 10,000 veggie miles on them with no problems. That's
just our customers. There are TDI VW's that are in Germany that have
close to 60,000 miles on them, and several in the US that I'm aware
of that has over 60,000. veggie miles on it.

The other myth/urban legend is that if there is a computer
involved with the injection system that you can't run SVO/WVO. I have
done 7 different makes of engine with computer controlled injection
systems, and not one of them freaked out when we flipped the switch,
and continue to run great.

As for the different types of injection systems, Rotary, inline,
common rail, unit injectors, and CAV. We have done them all, and all
work great.

The CAV does not have that many veggie miles yet, and the jury is
still out. Others have reported problems with them, but this is the
first one with our kit on it, so we will be watching it.

The great thing about running veggie oil is that it lubricates
allot better than low-sulfur diesel. It will actually extend the life
of your injection system.

I have a customer with an old car that was idling funny on
diesel, and idling normal on veggie oil. When he ran the whole
scenario by the guys at injection pump rebuild shop, they said that
the seals were probably worn out with age, and that the superior
lubricating qualities of veggie oil was what was keeping it alive.

__________________
98 K2500 Suburban 6.5 Luxo Barge

"We cannot change the wind - But we can adjust our sails"

I also do wvo conversions and must say that Greasles info is not completely accurate.

Either Greasel has not done their homework or is not presenting an accuraate overview of IDI conversion danger in an effort to encourage more sales. This is short sighted in my opinion..and makes me a bit uncomfortable since I doubt that Greasel will accept any financial consequances if DI diesel owners take thier info as gospel and convert..only to experience engine problems further down the road. I just don't think this is ethical.

Citing that "more than a few" DI diesel engines that have been converted and "not had problems" for 10,000 miles is not much in the way of "proof" that converting all DI engines is safe. In fact there is very good reason to believe that some DI engines are not suitable for conversion to WVO while others probably are.

I really doubt that many on this forum are interested in this however. Most folks planning on converting to wvo frequent vegoil conversion forums like the infopop svo forum

__________________
Dana Linscott
Vegoil converted truck...vegoil converted 1987 190DT, 300 series next.

http://vegoilconversions.netfirms.com/

what years did they introduce the direct injected diesels in mb? I am looking to by one but I want it to be direct injected cause i know the performance increase capibility

We appear to have a thread like this started every few months.

There are also plenty of threads about cars with motor failures on WVO.
Any claim that WVO has been run for extended time in cars without problems has not been supported by detailed independent studies. There are studies showing the problems that do occur though.

At least these guys admit they are in the biz of doing conversions & so are not providing independent advice.

If you want to put "death in a jug" in your motor, good luck!!!!

WVO may work ok in some limited applications. As far as daily drives & short trips, expect problems down the road.

There is much more to DI problems than just combustion, you may wish to look at high pressure stability as well.

__________________
Grumpy Old Diesel Owners Club group

I no longer question authority, I annoy authority. More effect, less effort....

1967 230-6 auto parts car. rust bucket.
1980 300D now parts car 800k miles
1984 300D 500k miles
1987 250td 160k miles English import
2001 jeep turbo diesel 130k miles
1998 jeep tdi ~ followed me home. Needs a turbo.
1968 Ford F750 truck. 6-354 diesel conversion.
Other toys ~J.D.,Cat & GM ~ mainly earth moving

I second that.

__________________
Professional greasecar installer
Austin TX


98 Jetta TDI with grease car kit + veg-therm (totaled)
87 MB 300SDL running on B99 / greasecar kit + 30 fphe
www.austingreaseguys.com

I am a believer in SVO as a fuel and I use WVO in my SVO converted vehicles. I follow Dana's advice and agree that the blanket statements made by greasel leave room for doubt.

I must say though, does anyone think that it looks bad to make a public statement with so many spelling, punctuation and usage errors? Granted, Greasel isn't in the editorial business, and if any of you read often, you will see that many editors aren't either.

My point is that there takes a certain attention to detail to make these conversions professionally with long term success. This is EXACTLY what Dana is referring to. I am suggesting that if I were to fluff my feathers and say that "my system works", I had better compose a neat and tidy letter mirroring that same ethic.

__________________
83 300TD (need rear wiper assembly dead or alive)
84 300SD Daily driver
85 300TD almost 400k miles and driven daily.
98 E300D *sold
86 300SDL *sold and made flawless 10 hour journey to new home.