Vegetable Oil as Diesel fuel for Model Airplane Engines

Here we have the Norvel .15 rebuilt with a custom made rod, brass bushed both ends. The crank has also been fitted with brass bushings on both ends. We now have a machine with zero slop in the system.

A prior experiment using soya oil and ether as the fuel was met with the justified criticism that perhaps it was just the ether that was burning. The clue was the heavy white smoke generated by the engine at full throttle.

So this time, I made up a mix of

6 oz of Sunflower oil straght from the fridge.
2/3rd oz of kerosene (11%)
2/3rd oz of Camp stove fuel (naptha)(11%)
25 drops of Amsoil cetane booster. (1%)

Much reading on biodiesel and SVO (straight vegetable oil) lead me to this formula. Special thanks to Kelly for the tip on using naptha in a diesel fuel.

And as you can see, it runs. Note that this time, we have MOST of the mix composed of oil as the fuel. On top of that,,,, note that we have no added oil for lubrication. As a two stroke, the Norvel requires an oil to be added to the fuel for lubrication. However, as the oil IS the fuel, it serves double duty as in burning for the go and oiling for the keep it from blowing up. Neat.

The idle is smooth and reliable and on this run was a tad higher than normal. Further tweaking got it down to 3K. Top end is down from a stock, kero/ether based fuel.

The main needle had to be turned OUT some six turns. The compression screw had to be backed off one full turn.

Starts required a high ether prime. Six or more prime bursts were needed to get a run but even then, it took a lot of coaxing to get the engine to run long enough to get hot enough for the run you see. The engine gets far hotter than with a stock, kero/ether fuel.

The sunflower oil along with the ingredients had a high viscosity compared to standard fuel. This likely accounts for the extremely rich needle setting.

Yes, lots of white smoke and we DO have oil coming out of the exhaust. But that's normal. Evidently, most of the oil IS being burned and SOME is still doing duty as lubrication.

Addendum,

As discussed on RCU, we have now come to the conclusion that not much, really, of the oil is being burned. The evidence is the gobs coming out of the exhaust. That also explains the needle setting, grossly rich. It takes that much fuel to get just enough of the kerosene and naptha to allow combustion. This experiment actually disproves the notion that the oil is burning and providing power.

Category:

Howto & Style

Tags:

• Norvel
• Diesel
• RC
• Airplane

[hopeso]

This project may get revived in the Spring. I plan to make up a "water jacket" that will do dual duty. One, the ambient, oil temp will cool the engine. Two, the heat will thin out the oil for better atomization. This will be assisted by modified, bypass ports along with packing the crankcase. The ID of the intake port will be reduced and a much smaller carb with the spray bar in the air stream will be employed.

Finally, to start with, we'll get the thinnest veggie oil that's made.

[hopeso]

From the dictionary:

Atomization:

To reduce to or separate into atoms.

To reduce to tiny particles or a fine spray.

To break into small fragments.

To subject to bombardment with atomic weapons.

The second definition applies here.

Liquid fuel or any fuel needs oxygen to burn. Light a liquid fuel in a container and the fuel burns slowly, at the surface, as it draws in the oxygen required to burn.

[hopeso]

For an explosive burn, as in the engine, the fuel needs to be mixed with air in a fine, spray mist. That's atomization.

[hopeso]

It begins at the carburetor, the droplets are carried along with the ingested air to the crankcase. From there, this mix air and fuel droplets is further and more completely atomized into a finer mist as it's injected into the combustion chamber when the bypass ports open. Remember, this is a two stroke engine.

Further atomization is achieved from the heat generated by the operation of the engine. That's why a cold engine runs better as it warms up.

[woollfen]

Why don't you try heating the veg oil mix to lower the viscosity and use pressure of some kind to atomize it like full size veg-diesel engines?

[hopeso]

That's a good idea. One way to do that would be to wrap the cylinder with copper tubing to pre-heat the oil.

This is a two stroke so it's the crankcase pressure that delivers the fuel to the combustion chamber.

Developing new bypass ports that improve atomization is an idea that I'll be trying.

[adamjonathanbell]

u might wanna wash ur hand m8 lol

[mikedrazen]

are you a very smart human?

you seem to know alot

[TheChickeneer]

Awsome, how much was it and where did u get it?

[dcopple]

What if you mix your veg oil with ether, and another ingredient to make it a little more volitile. May make it burn a little cleaner then. What kind of engine is it? Also, have read about dieselization of model engine and requiring less air mixture, but looks like it is running a little rich....

[MazdaArai]

Nice , my mercedes is vege oil powered as well.

[nitrorcx1998]

would i be able to run veggie oil in my savage?

[N37BU6]

Thanks for the detailed description, and for keeping it updated. That's pretty much what I figured was happening... it's a shame, really. Do you think scale makes a difference? I can see it being more efficient in a larger combustion chamber.

[669Banshee]

WOW Amazing MAN ! GOOD thinking and one way to save on money Then buying a GAl of Fuel at 30 bucks lol Can i Use thing On my HPI gas CAR ??

[669Banshee]

@RicardoDeLamonica Please Guy your Car u use to drive around is more Worse  then This airplane its a Test , u should worry about bigger things then This

[JGMagoo]

Could this engine be made to run on pure pump grade lo-sulpher diesel fuel with no ether or additives of any kind?