SVO/WVO risks? Anyone with high mileage on SVO?

[Mr. Flibble]

I have been doing more research into SVO and the benefits and risks to a Diesel engine. Seems that the Delica uses an Indirect Injection and a Bosch Mechanical Fuel Pump. Both things are positive when running on SVO. Free fuel and being mostly carbon neutral are big upsides to SVO WVO.

The downsides I have seen to running on SVO or a mix of Diesel/WVO are engine coking (rings, valves and injector nozzles) and engine oil polymerization.

What bothers me the most about SVO is the lack of many peer-reviewed studies on running SVO, and the very few vehicles are around that are high mileage on SVO*. This is not to say I am against doing so in a Delica - quite the opposite!

I am wondering what steps Delica owners are taking to ensure that SVO or WVO/Mix are not causing problems for the Delica engine? In my research, I have found that oil analysis, bypass oil filtering and frequent oil changes are all a good idea for the oil if using SVO/WVO mix. Another excellent idea is to purchase a compression tester, and check the compression of each cylinder before adding SVO/WVO, and continuing to do so at regular maintenance intervals. De-coking the injectors and exhaust are always a good idea (how does that impact the turbo? Bits of carbon hitting the turbine would be *BAD*) but I don't know how to do this on a Delica. (On a motorbike, I do!)

I know that there is interest in using water injection to keep the cylinders clean, but I remain skeptical of the ability for this to actually clean the cylinders apart from anecdotal evidence. (I have seen no empirical evidence that this actually cleans out carbon - whether by the fitted nozzle method, or the water added to clean the cylinders through slowly pouring a bottle of water into the butterfly valve or injectors.)

I say all this not to step on anyones toes or to ruffle feathers! I really really want to run on SVO! However, I also want to buy a really nice Delica, and spec it out just as I want, and the last thing I want is to have the engine fall apart on me!

* I know about the guys at http://www.drivetosustain.com, I am very interested in how that engine fares in the long haul!

[fexlboi]

...and the very few vehicles are around that are high mileage on SVO...

Not true. There are tons of owners with easy over 300.000km on WVO. Maybe not in North America and probably not on a Delica. Have a look at the Elsbett system which is around for decades in Germany.

I am wondering what steps Delica owners are taking to ensure that SVO or WVO/Mix are not causing problems for the Delica engine?

I'm reading a really good book about WVO. To sum it up what I have learned so far: Heating the oil to the right temperature before you inject it is the key task, also proper filtering/dewatering before you use it.

[BCDelica]

Here is a brief list of VO concerns, it's quote I put together when I started as a basic VO bible;

Since VO (vegetable oils) fuel research began in earnest the same basic problem has been noted with substituting VO for petrodiesel in diesel engines. It tends to leave carbon deposits which either directly or indirectly damage the engine and eventually lead to rapidly accelerated wear and/or catastrophic engine failure.

These deposits generally occur in three places...the injector tips, the manifold side of intake valves, and the piston (ring) lands/grooves. The process is generally referred to as "coking". Piston land Groove Coking is described at: http://www.websitetoolbox.com/tool/post ... id=1644578 and if individuals are interested I will create a separate discussion on the other two. It is sufficient to say here that injector coking generally tends to accelerate ring/land/groove coking and that ring/land/groove coking leads to the early demise of diesel engines run on VO.

In early testing of VO fuel engine longevity was very short. So short that VO was deemed to NOT be a viable alternative fuel. This was because VO tended to only partially combust due to its high viscosity at room temperature. The partially combusted VO tend to collect on piston sides and quickly damage the cylinder walls as well as do secondary damage to other parts of the engine. Reducing the viscosity of VO prior to injection by heating it dramatically improved the completeness of combustion but did not completely solve the problem.

But there are many things that individuals can do to delay ring/land/groove coking and the subsequent shortened engine life it causes.
The most basic are:

1. do not convert engines in the last stages of their life or in need of major maintenance unless you consider them disposable. If you DO at least test your crankcase oil for polymerization so it can be changed often enough to prevent gelling and the secondary damage this causes.

Quote:
To test for crankcase oil polymerization:
1.Retain about a cup of the used lube oil in a small jar.

2. Seal it up and refrigerate overnight.

3. Tilt the jar to see if the oil flows at all. Since refrigerators typically are set at between 37-45*F it may flow like molasses or tar...but it should still flow.

If it appears at all jello-like it indicates polymerization is occurring in your lube oil and that you should increase the frequency of your oil changes. If it remains jello-like after warming to room temp you may have advanced ring coking and should immediately determine if this is severe using compression tests before major engine damage occurs.

1. Change lube oil more often, likely twice as often, as usual.

2. Do not allow your injectors to become leaky. Leaky injectors speed up the ring/land/groove coking process since their effectiveness tends to quickly degrade. Use very "dry" VO fuel. Even very small amounts of suspended water (add link to suspended water discussion) tend to erode injector tips and allow leaking.

3. Do not add "performance" chips or other "power" mods to your engine. These are designed with diesel fuel use in mind and are not well suited to VO fuel use. They tend to add more fuel to the combustion chamber and so hasten ring/land/groove coking.

4. Do not switch to VO fuel until your engine is at normal operating temperature. The cooler the combustion chamber (piston,head,walls) are the faster ring/land/groove coking progresses.

5. Make certain that VO fuel is as hot as possible (200°F to 275°F) at the injector inlet.

6. Make certain that your purge cycles are long enough to completely purge VO from your injection lines and injectors. Starting a cold engine on cold VO will hasten ring/land/groove coking even in an engine with no other issues.

7. Do not ignore the manufacturers regular diesel engine maintenance schedule or any symptoms (hard starting, increase in crankcase oil consumption, excessive smoking upon startup, etc) which might indicate that the engine is not running optimally.

8. Have a compression test performed. Or do it yourself..Before you convert to VO. This will provide a good indication of how worn the engine is and possibly of problems that need attention before conversion. It will also provide a "benchmark" that can be used to compare later yearly compression tests to.

9. Make certain that your purge (diesel) tank cannot become too heavily contaminated with VO due to VO being "returned" to the diesel tank during purge cycles. Starting on a high percentage VO "blend" probably contributes to accelerated ring coking much as cold starting on VO does.

10. At the first sign of rough running, poor starting, reduced fuel economy, unusual increase or decrease in lubricating oil consumption, reduced power or unusual increase in black smoke, or any smoke, start investigation of possible causes.

[Mr. Flibble]

:)

Thanks guys! This gives me more confidence. I know it will work logically, but the idea of taking my Deli when I get it and then suddenly going SVO/WVO which I have not tried makes me initially a bit nervous! :)

Now I just need to figure out the best kit. I would like to carry a large amount of WVO underneath a LWB L400. We will see what kit's I source out!

[delicat]

Maybe not really high mileage but over 20, 000km on wvo this last year and a bit, no issues.
Do it right the first time and you should be a happy camper!

[Mr. Flibble]

Maybe not really high mileage but over 20, 000km on wvo this last year and a bit, no issues.
Do it right the first time and you should be a happy camper!

Thanks Delicat! I have read all your WVO posts (And BCDelica's, loki's and Adam's... I hope I did not forget anyone.).

In fact, all the Deli users here running on WVO were a huge factor in my decision to purchase a Deli for my next vehicle.