Chevy43,

How cool an engine can get and still run well was looked at a while back on this thread. It appeared, at least on the Norvels, that running cool, even on diesel, isn't that much of a problem. That is, with the fuels I was trying. You have a truly unique mix and I commend you for giving it a go.

At the moment, I'm downloading, on to Google Video, a clip where I fly the dieselized, Norvel .074 in the winter, on my MiniSport on skis. On stock, 40/40/20 fuel, I had no trouble starting and no adjustments were needed from a start. As you'll see, start the engine and just go fly, very much like glow. But again, on a high ether mix. The temperature was just a few degrees above freezing.

I just got a kit for getting raw vegetable oil to run with the addition of a 'secret' ingredient along with kero, gasoline, a diesel additive and the ingredient they sell. Will give that a go and see what happens. I got 22 ounces of the stuff and that's supposed to treat some 132 gallons. Yes, this was intended for the big stuff. Samples are available free for anyone interested.

The formula they suggest for one gallon+ of fuel goes like this.

1 gallon vegetable oil. Fresh or waste.
12.8 ounces of kerosene
6.4 ounces of unleaded gas
.7 ounces of Power Services additive. This is an anti-gel, cetane booster. Do WE need that??? Dunno. I'm going to try the Amsoil cetane booster.
.15 ounces of the DSE or Diesel Secret Ingredient.

The .7 ounces can be stated as 20cc, the .15 ounces as 4.5cc

Diesel Secret Ingredient, (DSE) is trashed on some Biodiesel websites but of course, you have to view that sideways, as this stuff competes with Biodiesel in that no treatment is required except good filtering along with water removal. All of this is done by simply pumping your waste oil through some filters and then adding the other ingredients. Not labour or energy intensive except for the pumps. And even then, a guy could use a hand pump.

For us, we'd just use a cheap veggie oil off the shelf with no need for filtering, I presume.

I ordered it on impulse, you never know, it might work in our engines by simply adding their mix, 80% along with 20% oil, castor or otherwise.

Looks like it'll take all night for the video to load to Google. Will provide a link tomorrow.

I was reading an old RCM mag from 1983. It was talking about making smoke with diesel fuel. The results were very good and you could tell the fuel was well atomized.

If you install a diesel preheater in the muffler you may be able to get the oil to atomize better. the author used copper tubing inside the muffler or copper tubing wrapped around a brass stinger inline with the muffler. I know that running smoke in a regular glow plane preheating really helps.

Auto Zone sells five foot lengths of copper tube for instrument lines and HVAC supply houses sell cap tube in 6-10' lengths. The tubing comes annealled but can be further softend by heating cherry red and quenching in water.

With a long enough piece of tubing you could get the oil temp pretty high before it gets to the carb.

The reason DSE is trashed on those forums is because you can run SVO or WVO without doing anything to it at all. The kerosene and gasoline do the thinning. Their ingredient is added for their profit not your benefit.

There is a limit to how cool an engine will run reliably. That's why we generally wait for our engines to warm up before we can make any reasonable settings.

Treven the difference in our engines is that vaporization is not part of the timing equation. In an injected diesel timing is adjusted for the delay from when fuel is injected to when it ignites. Part of that time is used up vaporizing the fuel. Hopefully our engines have vaporized the fuel by the time it's near TDC on the compression stroke.

We can't ignore the facts that the fuel needs to vaporize to burn in our engines. This is very different than injected diesels. Injected diesels spray fuel into the combustion chambers as fine droplets. The temperature inside the combustion chambers is far hotter than we will ever see in our engines. For those reasons injected diesels will run on virtually any fuel they are given. The larger the engine, the more this is true. The huge 100,000HP engines used in ships will run on straight crude if they pumped it into the tanks. They normally run on the lowest grade of oils No.6 or something. It has to be heated just to be pumped, yet these huge engines are of the highest efficiency reciprocating engines produced.

Here's my stance on the alternative fuel issue. There is no fuel that will work well unless its boiling point is below crank case temperature of our engines. Period. You will have to prove me wrong on this with facts, tests, and dyno sheets including BSFC figures before you will change my mind.

Good candidates:
Kerosene, we already know this.
Napthas, we have had some people elude to it, but no real tests.
Gasoline, I didn't have good luck with it, but that doesn't mean I'm done with it.
Diesel fuel, No.1 is essentially the same as kerosene. No.2 is heavier and approaches the limit of what will be acceptable. Treven's test shows this. Will there be work-arounds? I think so.

Here's my view on lubricating oils. I would rather buy my oil. I don't want to deal with making it. The cheaper the better, but quality is important.

Good candidates:
High quality Castor Oil: Klotz Benol, Maxima Castor 927, Castrol 747. These are modern formulations of castor oil and work when mixed with kerosene above certain temperatures. Some more work needs to be done to see what percentages at what temperatures before separation occurs.

Synthetic two stroke oils: These blend with kerosene and do not separate at low temperatures. A bit on the costly side, but not any more expensive than the above mentioned castor oils.

Motor oil: Plain old engine oil will also work. It was used years ago. The straight grade non-detergent varieties won't have additives to interfere with combustion. The only drawback might be carbon buildup in the engine, and to me the awful smell, synthetics don't smell all that great either. This is probably the cheapest and simplest choice.

Veggie oil: Straight veggie oil is probably not suitable due to its low viscosity. The modified oils may work but we don't really know what the qualities are. There is the drawback that you have to make it yourself, but it seems to be a relatively simple process. To me, this might be an option if we can prove the qualities of the produced oil.

Additives:
Ether: Obvious, this makes our engines work very well. Unfortunately it's hard to get and expensive. It’s high vapor pressure means some of it escapes the fuel mix every time the fuel bottle is opened.

DII: The nitrates or peroxides that improve combustion. There are many choices in the grand scheme of things but only, a few which are readily available. Real testing is hard to accomplish in my opinion.

Soot Reduction: It's not something that we really discussed but it came up with bio fuels and oils. Bio fuels and oils seem to have a cleaning effect in our engines. If these things do not work out in the fuel mixes we may need to add cleaners to keep the engines clean. I think regular automotive additives will do well here, but it still needs investigation. Some two stroke oils may already have ingredients that help reduce deposits in the combustion chamber.

Here's the dieselized Norvel .074 flying the MiniSport in the winter.

http://video.google.ca/videoplay?doc...30773&hl=en-CA

Yes, the fins were turned down. This was not to compensate for flying in cold weather. This was done long before, in the summer, as I was concerned that the relatively large fin area was forcing the Norvels to run too cool. I now no longer believe that and am satisfied that Norvel got it right the first time. An engine can run too hot but it takes a LOT to make it run too cool. Notice after I dump the plane, that I get a start with the engine covered in snow and definitely cooler than normal. That was a start at idle and the engine came up to temps pretty quick for good acceleration. The same engine, with the enormous fin area, will be flown again, this winter, to drive the cool running concept to the max.

On the super cool start, notice that the starter cup slipped several times. This wasn't because of hydraulic lock but due to oil getting on the rubber. A bit of wiping down of the cup and spinner solved the problem. But this custom made starter WILL stall with no damage to the engine in case of engine lockup.

This video also illustrates the torque and acceleration possible with a dieselized engine. This is an .074 driving a Cox, 8 X 4 grey. On the uplines, even when punching the throttle , the engines just growls into life and doesn't miss a beat. Love that little engine.

The fuel used was the 40/40/20 mix, castor and with Amsoil at 2%. Along with the extra cooling fins, I'll be trying various, low and no ether mixes. Lots of stuff to try in cold weather. Feel sorry for the LA and Florida guys, they just don't know how much fun this is. And at 40 below, we just hunker down in the shop and build,,, or repair, [:@] as the case may be.

Good day all,

I haven't had much time for testing lately and besides the weather hasn't cooperated much as well. I am going to rebuild my old PAW test engine and have doing some reading and research on what I need and how to give the cylinder/piston a rebore. Yes I know PAW provides this service but I figure if I don't give it a try I won't learn anything.

Andy, have you checked with Canadian Tire as to the availability of their branded Cetane Boost?

Also, it seems that this thread has been made reference to in a thread on the Barton forum site. For those interested see:

http://www.controlline.org.uk/phpBB2...r=asc&&start=0

And what with all this talk of oil and castor oil in particular, a little bit of trivea castor in french translated to english is beaver!

Anyone follow up on that lead about Klotz's Coxoc product? sounds like synthetic ether maybe? What little I can find on this stuff indicates it is pretty nasty and should be avoided.

cheers, Graham in Embrun near Ottawa

I fixed the wing on my Big Stik and made a new fuel mix:

4 parts my Black Brew + 1 part Davis plane.

I flew this for 3 hours of flying time today. It worked well. It will start without the plumbers torch. Hand starts can be done but it is difficult. It needs alot of choking till it gets warmed up. The air temprature was in the high 50's. Well see how it works when the temps are in the low 50's and high 40'- it dosen't get much colder here anyway.

A rough caculation says this is about 5 to 6% either if Davis fuel is 30%.

This mix will cost about $9.20 per gallon which is still pretty good considering I get 3 minuets of flying per OZ. My K&B .65 is more thirsty but it still alot cheaper than glow fuel.

I can still go to Kerosene insted of pump diesel if I have any more problems.

By the way my used oil is RPM Dello 400 15-40 Chevron Diesel oil. I don't think additives hurt at all an if anything they might help. My used oil is pretty clean ( although black ). In my Cummins it goes through the full flow filter thousands and thousands of times and is still good oil when I drain it. I have a powerfull magnet on my drain plug and there is no trace of metal on it. This is the only vehicle that I've ever owned that doesn't have some metal on the magnetic drain plug at oil change time.


Andy,
another nice video! Do you do those with the a head camera?
I think it will be difficult to run eitherless in those kind of tempratures but I'm looking forward to hearing about how things work out.
'
Greg, I agree with you to a point about the vaporization. Our fuels needs to vaporize but I don't know if the crank case has to be above the fuel's boiling point but the fuel does need to be heated on the way to the combustion chamber. You may be right though.

Treven.

I originally put flash point in that paragraph. The boiling point isn't quite right either as that's pretty high even for kerosene. but I don't think an engine will run on veggie oil because the oil will never vaporize. You need to get most of the fuel vaporized to have any kind of efficiency. we are already efficient but there is more to be had in theory.

Treven,

Thanks for the compliment but no, the video was taken by my nephew with a hand held, Sanyo camera. As practise makes better, he managed to follow the plane more closely compared to the flight in the summer. Yes, I am as well, looking forward to flying in the winter on various, experimental mixes. See below. [X(]

Greg,

Well, your statement about running just vegetable oil as fuel was a challenge I couldn't refuse. As you rightly pointed out about the run on Soya oil and ether, it could have been JUST the ether that was burning. Well, burning on to YouTube right now is a clip which contains the following text.

++++++++++++++++++++++++++++++++++++++++++++++++++ ++++++++++++++++++++++++++++++++++++++++++++++++++ +++++++++++++++

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 straight from the fridge.
2/3rd oz of kerosene - (11%)
2/3rd oz of Camp stove fuel (naphtha) - (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 naphtha in a diesel fuel.

And as you 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 normally 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 at 9K.

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 other ingredients had a higher 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.

++++++++++++++++++++++++++++++++++++++++++++++++++ ++++++++++++++++++++++++++++++++++++++++++++++++++ +++++++++++++++

Another run was with 50% Sunflower oil and 50% Naphtha along with 2% Amsoil cetane booster. In that case, the compression screw had to be backed off another half turn or so. Top end was down another 500 RPM. Idle was good but with ROUGH acceleration. My thinking is that various combinations of oil, kero and naphtha may give us a good, no ether fuel that anyone can make at home. Cost is another matter, I haven't taken the time to evaluate that, yet.

Pictured below are some of the ingredients.

Also pictured is the mysterious, MotoMaster cetane booster. It finally came in. The bottle reads that it contains mineral spirits and 1,2,4-trimethylbenzene. Sounds nasty and look, a skull and crossbones on the bottle. Didn't check the MSDS but I WAS very careful with handling.

A full afternoon of testing has confirmed that it pretty much works as well as the Amsoil which is octyl nitrate. The 350 mL bottle cost 10 dollars $anadian and at 2% concentration, that'll make 4 1/2 gallons of fuel.

So, straight vegetable oil, or SVO, WILL run in at least, a dieselized Norvel. Viscosity is an issue, as you correctly point out and that may be just a matter of more kero and/or naphtha. The question that comes to mind for me, is that, how does the engine know how much oil to burn and how much to retain as a lubricant? And how do the other ingredients contribute to this unusual situation.

Andy,
Thats a great result.
" The question that comes to mind for me, is that, how does the engine know how much oil to burn and how much to retain as a lubricant? "
My take on this is simply , the oil that comes into contact with the internals ,ie cylinder walls, piston crown, cylinder head are taken out of the combustion cycle. this could be due to vegitable oils unique dipolar molecule that bonds to metals, it is this bonding that makes them great lubricants too.
Stewart

Good answer, Stewart, makes sense. Thanks.

YouTube [>:] FINALLY [>:] confirmed the download as complete. I guess midnight (EST) is rush hour for them. Here's the link.

http://www.youtube.com/watch?v=3g0ri5kiRkM

Wow, That is a cool mix Andy. Your exhaust is as black as mine is running on my Black Brew mix.

I noticed as it got hot you had to back off on the compression which seems to be more the case with the non either mixes. The question is how does it run after a minuet of idling at that compression setting?

Are you doing the rod bushings yourself? Are you making them out of solid bushing stock on the lathe then reaming them to size after press fitting them in? How much of an interference fit are you doing for the press fit? Do they have an oiling hole?

I might try some Naptha for my winter mix. I'm really beggining to think that 20% oil is more than nessasary for my pump diesel mix.

How much of the oil burned?

I went back to Grahm's post #321 and Naptha has one of the highest auto ignition tempratures. Why did you choose to use it Andy? I know they use gasoline on the SVO mixes but real diesels don't have over - under compression problems.

Treven.

Treven,

Exactly right. The less ether, the more you have to be tighter to start and then to back off on the compression once running. And when I ran no ether with 10% cetane booster, this characteristic became even more prominent.

Right again. The bushings are undersized when pressed in and then both holes are drilled at the same time to ensure that they are square to one another. I use progressively larger bits in very small increments to sneak up on a bore that is tight on the pin. Then I make up a lap, on the lathe, out of plain old hardwood dowel. This will have a just snug fit on the bushing and then I apply coarse rubbing compound to the dowel/lap with lots of oil and spin the lap in the bushings a few seconds at a time till I get a fit to die for. Absolutely on the money, no slop but free to spin. The problem here is that if the crank to cylinder fit isn't EXACTLY square, you get binding through rotation of the crank. I've done many of these this way and out of some dozen, only had a problem with one. Not bad.

Yes, I upped the oil to some, 25 or 30% and nothing good, (but nothing bad) happened that I could determine.

The use of naphtha came about because just at the moment, I didn't have any plain ole gas to try. So I used naphtha instead. Worked fine, I guess. The mix was derived from DSE's formula for use with their magic ingredient. I forgot to mention that I mixed up their formula without their ingredient to see if it really did anything. After the runs on video, I added their ingredient and on this engine, on this day, it did nothing. As Greg pointed out and as the input on biodiesel forums indicates, there's no there there. But that jury is still out. We may need more of it on our little engines. More testing may be revealing.

So, after running some 12 ounces of the veggie fuel, the rods are still tight on the pins. Inspection under the head showed no carbon build up despite all that black oil coming out.

Greg,

How much oil is being burned is an excellent question and is good thing to find out to make the experiment more complete. How to do that? Long tube attached to the muffler with the exit inside a jar. Also, mileage will be another item to consider. There appears to be a LOT more oil being expelled than normal. Still, we know that oil is being burned. We have only 22% volatiles and we have NEARLY full power. And well, the smell is like peanut breath only in this case it's sunflower seeds.

That's how I would check. But we don't know that oil is actually burning. Based on the fact that the compression is backed out a full turn from normal I think that most of the oil ends up in the cylinder in an incompressible form, meaning liquid. We know that liquid fuel doesn't burn. Fuel consumption would be the other way to check. Yes there is only 22% volatile component, but that' doesn't mean the oil is burning. Try a mix of 78% castor and 22% ether and tell me what happens. I would say some is burning, but not much, based on how much ended up on your hand in the video.

Nearly full power? If you consider 90% RPM to be 90% power you would be incorrect. The prop has cubic power absorption to RPM. So at 90% of any given RPM you have only 72.9% power.

In my opinion mainly the lighter portion of the fuel is burning even though it's only 22% of the mix. Fuel consumption figures would easily prove or disprove this.

Hi Greg,

Your points are well reasoned. This is how this sort of thing happens. A guy gets a NEARLY all oil mix to "run" and comes to an erroneous conclusion that then gets spread around as gospel. Just because it's on the Internet. Your point about castor was on the money. I thought of trying that but ran out of daylight.

BUT, my reasoning is that if SVO works in the big engines, why not in our little guys? After all, the big ones use kero and also the SVOs. Somehow, the big atomization device handles the thicker oil/fuel. Why not ours? Ah, here's how to observe atomization in our engines. Take the head off, fill the tank and spin the engine with an electric starter. Do this at night with a flashlight providing the light. The spray out the carb was not evident in daylight. At night, it was amazing to see a fountain of spray droplets pouring out the intake. I've installed a screen and no more spray, the screen soaks it up and it gets sucked back into the engine. I anticipate better mileage and that'll be another experiment in the list of things to try already.

And about power/RPM. If the volatiles are only 22%, and only those are burning, surely we would now only be see something like 22% of the RPM over a stock fuel? Or at least far less than 90% RPM.

Maybe next to try is just oil and cetane booster. But sunflower oil is way too thick to be atomized in our little engines. Or is it?

Maybe I can find a very thin, vegetable oil to try. Any ideas? Coconut oil is out, for sure. [:-]

Well as I pointed out before there is one major difference. The in cylinder temperatures of full size diesels is WELL above what is needed to vaporize and ignite SVO.


The fuel is forced under pressure, minumum 3000PSI, up to 30,000PSI through an atomizer(injector). That's why they get away with it.

That's not logical. The engine at full throttle breathes the same amount of air whether is is being driven by fuel or another source of power like if you were motoring it with an electric motor for example, regardless of the amount of fuel or type of fuel. So what the difference? Take for example water injection in engines. It doesn't reduce the amount of power the engine makes, or can make, even though it is inert. The fuel has to burn to make power. To burn it needs air. We have airflow through the engine. and that is basically fixed for any carb, muffler, port timing, and RPM. We know that fuel burns within a certain air to fuel ratio range. If we increase the inert portion of the fuel(oil in this case) we need to open the needle to get an acceptable air to fuel ratio for the engine to run. The combustion process happens in a similar manner, but the incompressible liquid oil doesn't burn and just takes up space and absorbs heat in the combustion chamber, and is ejected with the exhaust. That heat the oil absorbs ends up as lost power output, I think.

I don't doubt that some of the oil is burning. There will be some oil droplets in the fuel air mixture small enough to vaporize during combustion and burn. This is why in post 353 fuel consumption will be the only way I will believe such a claim.

So power is basically determined by airflow. Why? the amount of available oxygen determines how much fuel you can burn.

Fuel A: (Methanol)
Mass Air/Fuel ratio = 6.4:1
Heat of combustion of fuel = 22.7 MJ/Kg

Fuel B: (Kerosene)
Mass Air/Fuel ratio = 14.4:1
Heat of combustion of fuel = 42.8 MJ/Kg

Say we have an engine that pumps 1 Kg of air per hour.
This means that on fuel A 1/6.4 of a Kg of fuel would be burned for 3.55MJ of energy input At 12% efficiency this is .425MJ per hour or .158HP per hour output.

On fuel B we can only burn 1/14.4Kg of fuel for 2.97MJ of energy input at 15% efficiency this is .445MJ per hour or .165HP per hour output.

These figures are rough and our engines always run far richer, but that just means that more fuel is used, but there is no more fuel burned than the oxygen allows. If a mixture of a fuel contains an inert component that just means that more mixture needs to be pumped into the engine per hour, but the air/fuel ratio of the burning components must be the same.

To clarify the inert portion of the fuel mix. If the above engine was fed a mix of 50% fuel B and 50% oil then it would consume twice as much mix, but would make roughly the same amount of power. It's the same as if you run the engine rich. You pump a lot more fuel through the engine and get no more power. The unburnt fuel is inert in this case, and is just dumped out the exhaust.

Andy, if the engine gets better than ~3.7 minutes per ounce of this mix, some of the corn oil is burning.

Interesting you comments Andy. I set off to find out what 1,2,4-trimethylbenzene is and why it would be used as cetane boost. What I found was interesting. Seems 1,2,4-trimethylbenzene is most common in diesel fuel treatments such as anti gel addtitives and is also listed as a very small percentage of #1 and #2 diesel fuel itself. In fact Amsoil Diesel Concentrate Performance Fuel Additive otherwise known as ADF is about 29% 1,2,4-trimethylbenzene (also known as p-ethyltoulene) and about 8% 1,3,5-trimethylbenzene the remainder being mostly forms of naptha.

http://www.amsoil.com/storefront/adf.aspx

msds here: http://www.amsoil.com/msds/adf.pdf

Used as one ounce to 5 gallons.

So it is interesting as you believe it works as well as the Amsoil Cetane boost - octyl nitrate also known as 2 ethyl hexyl nitrate. Two very different products.

I am not questioning that it appeared to work but I am starting to question just what the ignition improvers do for our fuels. Some descriptions of how our fuel burns is that the ether ignites first which then causes the other fuel(s) to ignite and the DII (amyl nitrate, iso propyl nitrate etc) modify the burning rate to eliminate knock, in other words when the ether goes off it just doesn't cause everything to off all at once causing detonation (I think that is right term, I will have to revue ealier in the thread on that discussion). If this is the case then perhaps some of the octane boost compounds sold for use with gasoline might have the same effect ? Remember my earlier comments about the F2d team racers adding tetra ethyl lead and ferrocene to their fuels for much the same purpose and I recall that they tended to use amyl nitrate or IPN in the 1% ranges as well. And of course kerosene burns at lower rate than gasoline, maybe the DII work their magic better with lower grade kerosenes?

Andy has some of that Klotz Nitro power stuff which contains nitro propane, have you tried that in place of the Cetane boost? (he may have I just can't remember)

Maybe all this cetane boost stuff has been a bit of red herring. Useful in our fuels perhaps but not the be all that was thought. After all, high cetane numbers or index is preferable but if you can't create a high enough temperature to cause ignition and get the fuel atomized then it just isn't going to go pop.

Andy, also you discussion of making your connecting is also interesting. There seems to be quite a number of diesel and 1/2a nuts that also have an interest in metal working. I wonder if there is enough interest that RcUniverse would consider creating an engine builders forum?

cheers, Graham in Embrun near Ottawa Canada along the sunny banks of the Castor river.

Yes, I think the same. I wrote something about it a few pages back. I have some octane booster to try next time I get a chance. Fuel chemistry is a complex matter. I can't pretend to know much about it. The fuel mixing is trial and error, but I do research what might work and what won't.

Trimethylbenzene is naturally occuring in crude oil. It's nasty stuff. Not much information regarding engines though.

I'm confuesed about what the cetane booster is doing as well. I don't think it changes the auto-ignition temp and it almost seems like it would make detination worse. But I have to say it seems like it helps.

I flew again today for about an hour on my Black Brew 4 parts to 1 part Davis Plane. I works well once the engine is warmed up.


I'm also wondering when we mix fuels with different auto ignition temps whether we get an average or we get different parts of the fuel lighting off at different times. If it is the latter it will allow us to time the layers of the combustion event to best suit our needs.

20% oil really seems like more than nessasary with pump diesel. I bet I could go lower but I really don't know how to tell when to stop so - maybe I will leave it alone.

Treven.

Greg,

Today's fun and games confirms pretty much everything in your post. Pictured is the rig I made to trap the oil. Yes, the jar is far larger than needed for the oil that will come out of a 2 ounce tank but I did need volume as a sort of after muffler. This rig was not all that quiet yet I still lost a full 1000 RPM using 40/40/20 fuel which was run first to test the rig.

So after running 2 ounces worth of the oil fuel, I added 8 ounces of kero to make sure to flush most of the oil out of the jar and measured. Based on the ratios calculated, of the approximately 80% oil in the formula, some 50% to 60% is being ejected as exhaust. So, as you suggest, only SOME of the oil is being burned. And of course, my tools and technique are quite crude and should not be taken as gospel. This experiment would have to be repeated a number of times with different engines, I think.

Interesting was that the thicker fuel benefited from a half throttle setting. I'm assuming that fuel draw was better. This was confirmed by pinching the exhaust tube at full bore. The muffler provides pressure to the tank and increased back pressure delivered more fuel. In both cases, forcing the heavier/thicker fuel to the engine was a benefit.

I also tried a mix that replaced the sunflower oil with castor and could not get a run. Then I tried pure oil with 2% and then 10% Amsoil cetane boost. No runs as well.

But the other day, I ran a 50/50 mix of sunflower oil and naphtha. What if I went to 20% castor and 80% naphtha. Would I get a run?

But here, http://www.copper.org/innovations/1999/09/oil.html a link provided by you a while back, talks of the use of sunflower oil as a lubricant and its characteristics seem to make it less desireable as a fuel. The link implies that sunflower oil also has quite desirable properties as a lubricant that we might benefit from. As in using less oil and more kero/ether.

So maybe I'll try 10% sunflower oil, 80% kero and 10% ether, with or without CB. Or a 10/90 mix with NO ether. Yeah, I might trash the rod but too late. See below.

Graham,

Thanks for taking the trouble to look into MotoMaster's version of cetane booster. Yes, it APPEARED to work, I couldn't distinguish one from the other when I ran the .15 on a standard 40/40/20 mix. But I've also managed to run the mix with NO cetane booster. Needle and CP settings were different and throttling changed a bit etc. etc.

And there was that run I made on the PAW here,

http://www.youtube.com/watch?v=8R9YL_KPRYE

with the 10% Amsoil CB on a no ether fuel. In that case, I had to back out the CP more than on a lower percentage mix. So CBs ARE doing something. And in that case, with the reduced compression, throttling suffered. Maybe MM's version of CB will behave differently? Making throttling not such an issue? Just need to try it.

But a few posts back, I found that in some cases, leaving out the CB provided some benefits. But we're calling it cetane booster when we SHOULD, maybe, be calling them ignition improvers. As in when you're trying to start your traditional diesel by hand. With electric starters, maybe we really don't really need the stuff. Somewhere it was suggested that what the automotive world called cetane booster performed the same function as amyl nitrate which is really an ignition improver, not a cetane booster. So you have a point about the red herring thing. This is getting complicated.

I haven't tried the nitro-propane as a diesel fuel additive yet. Have made notes on a half dozen or so things to try and the vexing thing is the weather. Rain, rain, rain. We had a good break today, sunny and warm. Didn't last into the evening, more rain and we even had an impressive thunderstorm. Outrageous, such weather at the end of September. It really IS teotwawki.

About the rod mentioned earlier. Pictured is the rod I made after I bent the stock rod. The aluminum grade is unknown as it's just a piece of rectangular material from god only knows where. It cuts easily but does not feel too soft. At any rate, mass makes up for grade,, or so I thought. When trying to get some of the dud mixes going, I eventually got hydraulic lock and banged up the rod. It bent in both directions as can be seen. Why? Well, my Sullivan MicroStarter stopped working due to a bad switch and I had to go to my stock starter for these runs.

One thing I did get from this is that Norvel cranks are TOUGH and can take the abuse. No worries ever, I think, about diesel conversions for Norvels. STILL have not been able to break a Norvel crank.

Hopefully I can tap the rod back into reasonable alignment. This should be possible as I now have a small bit of slop/clearance. Hope so as the spare rod was installed into my "good" .15.

I think I'll shelve the trimethylbenzene like I did the MEKP.

Treven,

You stop when you break something. Surely your R&D budget has allowed for that?

Well it's good to know that theory coincides with reality to some extent.

I'd like to see an engine building forum. Here's what I've been working on.

www.edfinfo.com/x/temp/other.html

I hope to be putting it to use shortly.

Treven,

An excellent suggestion. Kero has an AI of 420 and ether has 170. Quite a spread. So it's easy to see that the one brings the other up or down and we see the result in our engines. Gasoline and naphtha have an AI of some 250 and so, being better than kero, addition of same would average out to a better AI than kero alone. This is what Kelly was getting at, I think.

So we may just be back to square one in all of this. Our engines WILL run on just kerosene and oil. That oil can be a highly refined, modern grade of castor and it WILL stay in suspension as long as the ambient temperatures are reasonable. Or that issue can be eliminated altogether with the use of 50 weight Aviation oil. But for those of us that demand it, throttling suffers with little or no ether. Greater amounts of CB makes it worse.

A mechanical solution is being considered but some snags have been encountered. Theoretically the device should work but a chemical approach that works automatically and every time and never breaks may be a better way to go. But you never know.

The biodiesel and SVO and even crankcase oil was interesting and informative. Who would have thought ANY of this was doable. And ONLY doable if you use an electric starter.

Greg,

Your input has been very valuable and we all appreciate your prodding to apply more science and less speculation to all of this. I still keep forgetting that all I have to do is do a Google on any question and it's there, somewhere. Flash point, autoignition, cetane numbers. All relevant and contributing factors.

BUT, it's not over till the fat man leaves the stadium. My gut feeling is that there's modern chemistry available that was not considered before because, well, it's not SUPPOSED to work.

Maybe a winter's worth of a break from the problem will allow all we've learned, unlearned and forgotten to boil and bubble in our synapses and something strange and wonderful will emerge.

The .15 is rebuilt and ready for more abuse. Kelly has offered a new approach that has merit and will be tried. If only the #$%^% weather will hold. Global warming? HAH !!

Most interesting project you have on the go. And you're also into electric in a big way. Variety is the spice, for sure.

Where did you get those AI #s Andy. I got totally different #s like 210 C. for kerosene, 280 C. for gasoline and 550 C. for naptha - oposite ends of the scale.

Here is where I got my info:

http://www.engineeringtoolbox.com/fu...res-d_171.html

Personally I think that my free used RPM Dello 400 15-40 may be as good or better than single vis. 50 wt aviation oil. We need the oil to be thinner when it is cold so it can go through the carb. and thicker when it gets exposed to higher heat wich is what multi vis does.

Vegatable oil would be great if it works well as a lubricant but I don't trust it. As far as I know it has never been used ( except castor ) as a lubricating oil in any engine in modern times ( last 75 years or so ) One of my concerns is it may not have good viscosity stability at different temps. Say the rod bearing beggins to get hot due to friction and high loading like a little over compression - you sure wouldn't want the oil to thin out too much then....

I flew for another hour yesterday on my 5% either Black Brew mix. This works well. I still haven't tryed kerosene yet....