Hello Graham, et al:

My I offer some suggestions to help you with the No Ether Fuel?

As you have mention there are many possible combinations of fuels, Cetane boosters, and oils, but if you sit down and make a list of these combinations it is not really that large if you consider the fact that the idea is to be able to make a “no ether fuel” on most continents of the world. I’d like to list some of the possible components and also list their pro’s and con’s.

First we need to look at what goes into our diesel fuels.

1. Fuel
2. Oil
3. Ignition enhancers (ie. Cetane Boosters)

Next, we need to discuss the Energy Density (ED) of these fuel/oil/Cetane booster combinations. What do I mean by Energy Density (ED)?

Energy Density (ED) = is the amount of store potential energy to do work, or BTUs divided by volume, or BTUs/volume, yet another way of looking at it is the BTUs per drop of fuel.

Other definitions required for this discussion:

Cetane = ease of auto-ignition from compression of a gaseous mixture of fuel/air.

Compression Ignition = the required compression level (i.e. 20:1 or higher perhaps) of a fuel/air mixture to create the required amount of increase in the air temperature to auto-ignite your fuel/air mixture. You must consider the rate of compression not just the compression ratio. Thus if you use an electric starter you will have a much higher rate of heating, enabling you to start the engine much easier. This is a very important concept that Andy has proven with the use of You-Tube movies and his small starter. The electric starter helps to increase the rate of temperature rise of the fuel/air mixture with in the cylinder.

Fuel Viscosity = Fuel with high Cetane ratings usually are more viscous and are more difficult to atomize and vaporize. Solids and liquids do not burn! They must be vaporized or turned into gases and combined with an oxidizer (air) to burn. So if the fuel is viscous it is more difficult to burn than a similar lower viscosity fuel. This is very important in little engines. The electric starter greatly assists in atomization of the fuel/air mixture helping in startup yet again. Please note, Ether and Hexane as exceptions, they have a high Cetane and great ease of vaporization, but very low ED.

Okay, now on to fuels of possible use for your experimentation.

HEAVY FUELS,
Kerosene
Auto Diesel #2 and #1
Jet A
Deodorized home heating Kerosene
Lamp oils

“Special Heavy Fuel”
Bio-Diesel (Keep an eye on this one, since I think it is a very good choice)

These fuels all have High ED and High Cetane rating, and High Viscosity and low Volatility.



MEDIUM FUELS,
Coleman and Ozark Camper Stove and Lantern fuels.
BBQ Lighter Fluid

(Ozark Camper Stove Fuel is WalMart’s brand and cost about $3.80/gal USD)

These fuels have modest ED, modest Cetane rating and Low Viscosity, modest Volatility.



LIGHT FUELS.
Ether
Hexane

These fuels have low ED, high Cetane rating, and low Viscosity, Extreme Volatility, but also have high cost and other negative factors.

Okay now what fuel to use?

If you want a “no ether fuel” you need to consider a substitute for ether which is a good Cetane improver and a low viscosity, highly volatile fuel that is easy to vaporize.

Okay, then what happens when you remove the ether? The viscosity of the fuel goes up, the ED rises a great deal, and the volatility of the fuel goes down. Remember ether is very volatile, low ED, low viscosity fuel. Okay, “so what” you say, well the metering system is now not calibrated for this fuel, the needles get very sensitive and the idle is not as low and smooth.

How do you fix this problem?

I would suggest that you use a heavy fuel blended with a medium fuel to decrease the ED of the fuel, This will also lowers the viscosity allowing for better atomization and vaporization of the fuel.

Perhaps a 50/50 mixture of one of the Heavy Fuels with Medium Fuels would work.

It is important to match the ED of the original fuel design for the engine. If you are using a PAW engine the carb is set for diesel use and has a smaller throttle body bore, which is preferred. If you are using a converted glow engine then you must consider reducing the throttle bore in addition to lowering the ED of the fuel.

Glow engines burning standard glow alcohol fuels may require a fuel to air ratio in the region of 10 parts air to one part fuel. A Kerosene and oil mixture may require a mixture on the order of 20 parts of air to one part of fuel. Now you get the idea. The ED must match the design of your fuel metering system. I would suggest that you try straight Coleman or Ozark fuel or BBQ Lighter Fluid for a Glow conversion engine as the fuel component. Since your ED will match the metering rate of this oversized throttle body much better, but you will need more Cetane booster to recover the lost Cetane rating of these fuels.

The trick is it to lower the ED of the fuel without lowering the Cetane rating of the fuel, but if you have a limited number choices, so you must use the Cetane booster to recover lost Cetane ratings. A Very Important Concept!!!!

Now you need to consider the Cetane Booster, which I will only talk about the Amsoil Cetane Booster since it is safe to handle and can be purchased in Europe and Australia too.

I would suggest that you start with a mixture of at least 2% Cetane booster and gradually increase this percentage up to 15% in initial tests to discover the effect of excessive booster. I recommended to Andy a run of 10% and he confirmed that it did not harm the engine.

You need the Cetane booster since you have removed the ether from the mix. How much I don’t know, but it will not harm your engine, just back of the compression ratio some if it sounds odd. We could all benefit from a good test.

Oil:

Okay, this is dangerous territory since everyone has a favorite and their own ideas, but here are some facts.

Synthetic oils are not going to burn and increase the ED of your fuel, which is very good. They are a dilutants, like the medium grade fuels. They will not carbon up your engine and they are low viscosity in comparison to Caster Oil . Some synthetic oils are very reasonable priced I.E Cool Power cost $7.50 per QT USD.

In summation: Synthetic oils are low viscosity (good), low ED (good), will not burn to carbon (good) and are required in lower concentrations (good), and can be found for modest cost. Very good. I’d strongly suggest these oils!

Non-Detergent Motors oil are good low cost choice and work well, but they increase the ED and do burn to a degree within the engine.

Castor oil is okay, but gums up engines, burns to carbon in the engine, and increases the ED of the fuel, all of which are not good. Plus it is very costly.

I would suggest Morgan’s Cool Power (green) oil, Klotz 200, or some of the Amsoil products like Interceptor, but I don’t think the Saber version from Amsoil will mix with Bio-diesel. See below comments:

Okay we have just about made it to home plate now. So here is my best suggestion;

Bio-Diesel (BD) is low cost fuel, easy to make or now getting easy to buy in many towns worldwide. It is very safe, since you can eat it. It has a very high Cetane rating. As an example Kerosene has a Cetane rating of approx 45 and BD can have a Cetane as high as 60!

Look here to see how to make Bio Diesel fuel: http://journeytoforever.org/biodiesel_make.html

You most likely will need to use synthetic oils in combination with BD and I don’t know if Cetane booster is required, which would be really nice news. BD is made up of long unbranched chains of hydrocarbons, which is great news, plus it has a great deal of oxygen attached to the molecules, which maybe wonderful news for our purposes. It may work like Nitro in our small engines to boost combustion efficiencies. It has modest viscosity so it may meter quite well. I don’t know if it will mix with the Medium Fuels without the correct synthetic oils, but I’m sure it will mix with the use of Cool Power or other synthetic oils. It burns clean with a very pleasant odor and almost no smoke. It has a nice clean odor in general terms, unlike Kerosene, or Jet A. It cost about $3.50/gal USD.

One more idea I passed on to Andy was using Pre-heat to get the engines up to running speed temperature at startup, so that you don’t have to adjust the compression screw. If you make an iron out of steel tubing with a small-insulated handle it can be heated in the field with a torch and set on the cylinder. This preheat will allow the engine to start instantly and not require any adjustment after you initial setting have been make to the engine.

Resistive heaters are also possible using small heating elements from portable soldering irons.

The entire portable soldering iron: http://www.starkelectronic.com/wahl.htm
The tips are only $6.50 each and run on 3 volts: http://www.starkelectronic.com/wahltip.htm

Use them sort of like a glow plug, but I’d call it a preheat element to keep from confusing the topic.

I hope this information is helpful,

Kelly