RE: Substitute for Ether
 

Gold start

When (if [:@] ) I fly in winter I boil water to the thermos and pour to the (glow) cylinder head just before starting.

Before that I used "startspray" to the carb which I bought from car part shop and which is mostly ether I believe.

RE: Substitute for Ether
 

The Power Service Diesel Kleen is something I looked at and tried. I gave up on it because I don't really know what percentage of octyl nitrate is in it. MSDS says 5-40%. All the other stuff in there sounds nice for a full size, but I don't think it benefits a model engine. I gave the bottle to my old man to burn in his Cummins. The Amsoil product ends up quite a bit cheaper in the long run.

My four strokes are clean as a can be, even the one I flew which had 2-3 hours of time on it. The only thing that gets any carbon buildup is the exhaust valve face. Early this year I had a little soft carbon buildup, which I was expecting and didn't note the conditions. I think that's when I was running excessive CR and motor oil or Sig castor, can't remember. My latest tests have been with Maxima Castor 927, which is similar to Benol.

RE: Substitute for Ether
 

Hi Greg,

You're right, the Diesel Kleen shows an octane boost of 6 as opposed to an octane boost of only 4 for the Diesel Fuel supplement. The latter is intended for winter and contains anti-gel.

BUT, if one is interested in giving diesel operation a try, as in right now, they can do so by buying the materials locally, without waiting. And, as we find, ANY amount of ether of any grade will help so any brand of Quickstart, even house brands will contribute to the fuel formula. So any Canadian Tire store or its equivalent will get you on the road to stinky power.

In any case, I'll give the new stuff a try and just see what happens. I think I may try 25% of the Amsoil 2 cycle stuff to maybe compensate for the viscosity issue,,, if its any issue at all. Yes, I do have spare parts. [:@]

That carbon was unusual, I suspect it came from running the Aviation oil.

RE: Substitute for Ether
 

You are finding all sorts of interesting stuff Andy.

I have run across the Power Services Products in searches on the internet. Only Canadian source I could find was Bennetts dist. in Winnipeg and they didn't list any retail source east of Hearst.

Interesting that you found it at Canadian Tire. I have never seen it there, might be just a local thing as it is not on their website either. I will have to look a little closer next time I go.

However, searching the Canadian tire web site I did find a product called Motomaster Diesel Cetane Boost (a repackaged or simlar product to the Amsoil Cetane Boost maybe ?) but checking with their online store finder it was "temporarily out of stock" everywhere. Might be a new product and the paper work/documentation is just not quite up to date. I called Canadian Tire and they are checking on it for me. This might be a cheaper and easier to get alternative to the Amsoil product. Canadian Tire part number is 38-0710-2 - ask about it the next time you are at the local store.

Also, did the Power Services product you got have a Canadian Tire stock number? Do you still have it? I would like to ask here about it.

The Diesel Kleen sounds more appropriate for our use. Plus the added lubricants or whatever might allow use to add less oil to the mix and still balanced out with a usuable fuel at similar cost.

Yes indeed, simplify with the ability to get everything locally and if I end up using a bit a of ether from the lower % brands then that will be just fine. Still the goal of something better is still an interesting goal to continue working towards.

cheers, Graham

RE: Substitute for Ether
 

Andy,

Stacked Anodized Disk:

Last year I mentioned these facts to you:

I found some interesting material in an old book at our library from the Department of Defense several years ago, or it was a history book on the H-bomb, I can’t remember the exact source. During the 1950’s when Edward Teller was trying to convince the DOD to make the Hydrogen Bomb program, it was necessary to used cryogenics for the construction of these test devices. It was found that a stack of thin layers of Aluminum alloys disks that had been anodized on both sides were excellent insulators. My guess was that this was used to support structures within the cryogenic tanks that contained the various isotopes of Hydrogen. I know you have the ability to anodize since I’ve seen your wonderful work. If you anodized a sheet of AL and then made a simple stamp you could stamp out many disks and stack then for good “disk diesel head”.

A good source of thin Al sheet stock is at the local newspaper printer. Every sheet of newsprint needs a corresponding sheet of AL that they then recycle. They will give you a nice piece of AL for free. I think it is about .010 thick. Scrub off the printed material and dip it into your anodize process. A stamp made out of a piece of steel would be very simple to turn on the lathe. Something about the Anodization Process helps to make a good thermal brake. Even without anodizing it would make a good insulator, so copper sheet stock would be a good test also.

The nice think about using just a stack of disks or just a very thin plate is the fact that any engine can become a diesel just by removing the standard head shim and installing a disk and then reinstalling the normal head over the thin disk(s). A screw coming from the glow plug hole could push down on the center of the disk to offer a very small CR adjustment. Since the thread is non-standard it would be easy to take an old glow plug, remove the element and press a small rod into this volume once occupied by the glow element. This rod would extend past the glow plug end a small distance as required to reach into the cylinder to press on the back of the AL stack of disk to “oil can” the stack very slightly to affect small changes in CR.

One more important objective maybe to offer an insulation blanket to the aft side of the thin disk(s), this would offer an increase of stored heat energy to help light-off each ignition stroke. A “heat flywheel” so to speak.


Oil:

Cool Power oil is very thin too. Perhaps it looks like about 20wt motor oil. One of the nice features is that it blows off and away from your aircraft during use. My plane is much cleaner after a flight with Cool Power.

Kelly

RE: Substitute for Ether
 

Graham,

The Power Services Diesel fuel Supplement has a CT part number 38-0726-6 at 4.99 for the 32 ounce bottle. However, I'm going to return it in favour of the Diesel Kleen for that products superior cetane boost.

Thanks for the tip on the Moto-Master cetane boost. I'll check with them today.

Something better, cheaper, available, might just make more guys interested in what we do. And imagine if the stuff didn't stink. And your plane was cleaner. Hey, I don't mind, I don't even notice.

Kelly,

Yes, anodize is good insulation and that may account for some of the effects we're seeing in Norvels. Plus, that would account for the relatively large fin area on the anodized cylinder. Wonder what would happen if one were to strip the anodize off the outside of the cylinder? Easy to do with liquid drain cleaner and a bit of steel wool. Going to go up to the Daily Press and see if they've got that material. Thanks for the tip.

I like your analogy,,, a heat flywheel.

If Cool power has a similar viscosity to the Amsoil, that is encouraging. Interesting coincidence that both the Amsoil and Cool Power are green. Wonder if Kermit had a hand in any of this? ;)

RE: Substitute for Ether
 

Am I to take that you use an ether spray to help starting in the winter? That's a novel idea and may be just the ticket. BUT, I've not had any problems starting in winter, glow OR diesel. Not tried all kero fuel in winter yet, though. Hmm.

RE: Substitute for Ether
 

Andy,

Anodized Disk update:

I had one further idea to add to the layered anodized disk concept. The ideas of stacking various alloys maybe beneficial. If the first disk, which is in contact with the combustion gasses is Copper it may have two effects. First Copper has a higher specific heat, thus the “heat flywheel” is slight larger, and second Copper will anneal with each heat cycle, helped to reduce cracking.

I believe we discussed this last year and you test a single very thin disk and it eventually work hardened and failed, but it did run well until failure. I believe DDD had a Teflon disk for the .049 engines and it held up okay for a while, but it eventually failed too.

If you stack several layers of AL disks behind the Copper disk it may holdup to the constant hammering and also give you the required thermal break.

I think a center support coming from the glow plug area, I.e. (center area of the disk) would also reduce this flexing and again perhaps allow for a small CR change while running. The idea of an old glow plug with a pin pushing on the back of the stack would greatly reduce the flexing of the disk during operation. I believe your thin test disk did not have this support. Can you confirm this comments?

Perhaps Mr. Davis will give us some advice on this matter?

Kelly

RE: Substitute for Ether
 

Yes with glow engine and if I recall it's name was "Pilot Spray". I have seen an old truck which had a mount for it inside air filter housing and driver siphoned when necessary pulling a knob on dashboard. But when boiling water idea was "invented" ether spray was unnecessary. With cylinder to the side it is easy and safe to pour water.

RE: Substitute for Ether
 

Anodizing metal makes it insulative for current. They were used between semiconductors and heat sinks decades ago. They might insulate heat as well but I think not much.

RE: Substitute for Ether
 

Yes, a good point, the amount of insulation is small for each surface, but DOD found that a stack of disks was a surprisingly good insulating device. If I remember correctly they needed to support devices that were chilled to extremely cold temperatures of Liquid Helium. I don’t know the number of disks or size of the disks, all they said was “anodized stack of metal disks”, which leads me to think that they must have been Al alloy. It may only work at extremely cold temperatures of Liquid Helium, since matter acts very odd at near zero, but it may work on the other extreme too. . The air trapped between the thin disks is an improvement over a solid disk.

Andy can anodize up a set of disks for testing since he has the equipment.

I would like to invite other ideas for good very thin materials that could be applied or stacked between the disks that cold handle our cylinder temperatures to act as a thermal break. . I have seen ceramic fabric that may work. Any suggests fellow Diesel Heads?

Your hot water bath idea is similar to my hot iron idea. Just another way to preheat the engine. I think this is a good idea too, hot water is very safe. Heating an iron with a torch could lead to a forest fire. Ouch. It worked great for me, but some may not have a torch.

Can you buy ether in Finland? What does it cost? What sort of container does it come in? How about Amsoil products?

Kelly

RE: Substitute for Ether
 

Kelly,

Another version of this would be to separate the discs with extra copper gaskets. This would ensure a layer of air for better insulation.

I may have been remiss in reporting back to you but in fact, I DID try a couple of copper discs on the .15 last year with a threaded device pushing on the disc for fine tuning the CR. What happened was, we got a bellows effect and it didn't take long before the bellows failed. The copper got brittle. This may happen to the aluminum as well but that is still to be tried. But here's where it might work. Once you settle on a fuel formula, install the device, fine tune it to that fuel and from there, treat it as a solid disc. With the insulating properties anticipated, It just may start more easily and provide the heat/hot spot effect we're looking for eliminating any need for further adjustments.

Right now, though, I'm concentrating on getting a fuel that can be assembled from local ingredients to be used in ANY diesel engine. See below.

Graham,

Went to my LCT (local Can. Tire) and they didn't have the Diesel Kleen but they DID say that the Motomaster cetane booster was on order and would be in in about a week. I'm anticipating that it may be made for them by Amsoil. If that's the case, we now can get all the ingredients locally, a GOOD cetane booster, synthetic oil and plain old kerosene. And with a non adjustable head, we'd have a very cheap diesel system.

RE: Substitute for Ether
 

Andy, good idea, I think you did tell me that one test did fail. Where you able to adjust the CR with your CU disk stack?

Yes an air space, but it may allow the bellows effect. Perhaps an adhesive like JB Weld? Just thin layers on each diskette and build up a disk. If you mixed micro balloons into the JB Weld it would make a good insulator.

In fact that lightweight Spackle to fix dry wall may be perfect. It is mostly fly ash; very light weight and sticks to any thing. Just smear on a light coat and it will dry hard. It should insulate well. It will hold up to heat well too since it has mostly ash. Perhaps Al alloy will not work harden as fast.

Other suggestions welcome.

Good luck with the Cetane Boosters!

Kmc.

RE: Substitute for Ether
 

Just got back from testing a mix using the Amsoil 2 cycle oil on my Norvel .074. This time the formula was 25% oil and 75% kerosene with 2% Amsoil cetane boost.

I got a good top end but throttling went WAY south. I couldn't get it back, thought I'd hafta wait till next spring.

Well, actually, no matter what I tried, I could not get a reliable idle. The barrel needed to be open far more than normal just to keep the engine running. Curious. Didn't even bother taching it, no point. Ah well, it was a good try.

So, to get in a little flying and not waste the mix, I added an equal amount of the 30/50/20/2 mix, as in 30% ether. This made it a 15% ether mix with nearly equal parts synthetic and Aviation oil. Got a very good top end and the idle came back. Not all the way, but enough to use up the fuel. A six ounce bottle, three flights of 25 minutes or so. That's good, the Amsoil synthetic won't go to waste.

Next to try will be 40/40/20/2 with 20% synthetic oil. And maybe a half and half synthetic with castor blend.

And, when mixing the Amsoil synthetic, it was found to be really a nice, deep blue and NOT green. My bad, looked green in the translucent bottle with the fluorescent lights in the basement. Outside, natural light told the tale.

So, when we get the Cool Power oil, we shall see.

OK, so far, the perfect, homemade mix for any and all engines still eludes us. If the LCT cetane boost is the real deal, then we are close, including Aviation oil and kerosene. And once again, the flying is the deal and so far, only the .074 has flown on these strange brews.

Kelly,

Yes, I was able to affect the compression well enough but any more than three or four adjustments would crack the bottom disc.

But lately, I'm having trouble with the CP drifting. A locking lever is the solution but the *^&^%$ things are a pain in the north end of a south bound mule. A long, ball end, socket screw driver is a total pleasure to use and bloody safe. That tommy bar on the PAW sure looks good sometimes. There's a good solution to this and I'll come up with something.

That may have to wait though, goin' fishin' tomorrow, if the weather says yes. Forecast is ambiguous. Remember when they said it WOULD or WOULD NOT rain? Now they hedge, with chances in percentages. Fine, thanks a lot. Later all, got some new tackle to try.

RE: Substitute for Ether
 

What is the goal of the insulated head? I don't quite understand the benefits. I understand the need for reduced heat transfer in the cylinder to enhance starting. I don't understand the need for a hot spot while running. it would seem to me that if you have enough compression for starting it will be enough for running. Additional hot spots might over advance timing at high throttle settings. I thought that Andy had better results with the heat sink head on the engine. That allowed a higher compression at full throttle which resulted in better idle. Did something happen which I missed?

I noticed in my four strokes that if I let the engine cool off at idle it would take 5 seconds or so of full throttle to reach peak RPM. It would instantly jump to within 500RPM of peak, but took a little time to reach it. I accounted this to delayed ignition timing due to lower engine temperatures. With ether I would have a different situation. Upon opening the throttle the RPM would peak out and after 20-30 seconds ignition timing would advance to the point the engine knocked and RPM dropped. Potentially some ether or something else could put me between the two problems, where I would like to be.

Where can I find information about andodize and heat transfer that you are discussing? Everything I've ever read says that heat transfer of aluminum is improved at least some to sigificantly with anodize compared to bare machined aluminum depending on airflow conditions.

I bought a bunch of Norvel parts off fleabay a while back. There were some diesel parts. Some aluminum discs that were appearently being used with a Davis head on a Norvel .061. There were also some turned steel head buttons. Some were obviously used. I can't remember the seller now.

RE: Substitute for Ether
 

Greg,

Go figure, big fishing trip tomorrow, can't sleep.

Not so much an insulated head but an insulated CP. The bottom layer of the CP will get quite hot and if you prevent heat transfer and try to retain that heat better,,, you may affect combustion more easily at start and thus not requiring a higher CR. In that sense, a start without having to play with the CP.

And then there's the issue of advanced timing being needed the faster you turn and this happens automatically as the engine heats up more at full bore. BUT, if the EFFECT isn't linear to the DEMAND, then you might stumble, get a miss, a knock or whatever. So altering any of these parameters may bring these elements closer to where you want them to be. A high ether fuel ignites more easily and so too, might a hot spot of some kind, eliminating the ether without affecting the better throttling you get WITH ether.

Kelly's description of a heat flywheel may help to visualize the concept. At full bore, the heat of combustion determines the heat of the engine which has a feedback effect, determining the CR. That's why we need to wait till the engine comes up to temps before attempting any radical CR or needle changes. And even there, we have to wait till any change we make has its effect to see where we went.

So we have a certain cylinder temperature at full bore and, as you point out, at idle, the temp goes down and this changes the optimum CR and so on. With a hot spot, the spot retains enough heat to mediate this effect. So idle combustion is kept hotter to more nearly match the top end. Flywheel effect.

The large, finned, heat sink head, drove the engine to run cooler at the top and thus was nearer to the temperature at idle and this occurred because without so much prop blast, the fins didn't have as much effect at cooling, at idle, as at full bore. In reverse, a heat flywheel was created in this manner.

Well, that's the theory, anyway.

So maybe the perfect solution is a lot of fins with a hotspot deal within the engine. Lots of fins is easy, the passive hot spot is the problem.

I've not done any research on it, only have Kelly's comments but I do know that an anodized surface has a honeycombed structure. As such, it can hold pockets of air that simply sit there without circulating and thus act as an insulating blanket of sorts. But colour anodized may be something else. We all know that a black surface absorbs radiated heat better than a white or silvery one. It's my understanding that a black surface also, in turn, radiates heat (or cools) better than a white or silvery surface colour. As well, the pockets are filled with dye and are actually closed after colourizing to hold in the dye and colour.

So black absorbs, but also gives off radiated heat better and this may be what you're referring to.

And the Norvels, especially the .06 has far, far, more fin area than say, a Cox. Ought to run too cool as most would opine. But it doesn't, along with a Cox (also accused of running 'too' cool) and I've burned myself on both Cox and Norvels. So *** [X(] as the kids say. Could be that the anodize has some insulating effect and THAT's why Norvel makes them with so much cooling area.

Just as soon as I get caught up, I'm going to run an .06 stock and then strip the anodize off of the outside and then run it immediately. Should run cooler as the theory goes. No, no temperature gauge, just an observational experiment as in how fast a drop of water will boil off just after shutdown.

RE: Substitute for Ether
 

Repeat post deleted.

RE: Substitute for Ether
 

Andy, "Goin' Fishin'" - sounds like retirement suit you.

All interesting stuff.

I had a couple of thoughts. From the descriptions I have been reading it seems no or low ether mixes run well at full throttle but suffer in the idle; that is compression is correct for open throttle but compression is too low at idle. Some of the references I found regarding F2C fuels mentioned the use of Tetra Ethyl Lead or Ferrocene as an additive to allow them to run at bit higher compression. Sounds counter intuitive, adding something that increases Octane in gasoline to improve the burning of Kerosene in a model diesel engine.

So, what effect would we get if we added (.5 to ?? % ) of the common off the shelf Octane Booster (Lucas Octane Booster is commonly availabe and Canadian Tire has that as well, Amsoil has one simply called Amsoil Octane Boost). Might this allow us to run at a slightly higher compression to affect a better idle while at the same time not adversily affecting top end? I don't have an engine set up with a throttle so would not be able to test this idea.

I got some B20 biodiesel and I hoping I will be able to some testing later this afternoon, details at 11.

cheers, Graham

RE: Substitute for Ether
 

GrahamC

Exactly on target.

Wide open throttle (WOT) is great since the rate of compression is very high, since high piston speed relates to an very high internal compression rate of heating the gasses, but when the piston speed slows down (at idle) the rate of compression of the gasses decreases, thus a lower internal gas temperature is achieve. It appears that ether mitigates these concerns and perhaps a good Cetane booster may work as well as ether, but at what concentration?

Note: I’m not talking about compression ratio(CR), but the rate of compression of the gasses. It is the rate of compression that gives us a rapid increase in the gas temperature. If you slowly turn the crank on any engine your still have the same CR ,but the Rate of Compression of the gasses is slow and you will not achieve the required temperature to auto-ignite a fuel/air mixture.

I see this problem with my PAW .49 engine, often my home brew has a low ether content, I have to over compress the engine to get a good idle, but then it complains dearly at WOT. This engine drinks a lot of fuel so I’m always trying to get by on a very small amount of ether.

It also appears that some synthetic oils many interferes with the Cetane rating of the fuels. I hope that Bio-Diesel has such a high Cetane rating that the dilution of synthetic oil will not destroy the low speed operating characteristics.

D-Star’s generator set most likely runs at WOT only, and the Kolibri would only need to moderate its power settings from ½ to full throttle since it is a VTOL craft. If it had a power to weight of 1.5 to 1 then ½ power would be the same as idle. So D-Star may not able to achieve low idle speed in a two-stroke engine using JP-8 (Jet A).

Greg’s comments that his 4 stroker’s idles is encouraging, and I wonder if the exhaust valve is acting like a “hot-spot” to hold heat energy for low speed operation.

Thin Disk problem:

It appears that thin disks of any sort will go into Forced Harmonics with the combustion pressures and intake draw making the disk flex and failing from work hardening. Thus a flexible disk will eventually fail, but a hot spot may be the trick to keeping and holding a good idle.

One more hot spot idea:

If the disk was rigid then it could be a three-part affair. One part looks like a thin donut and the second part look like a normal disk but it has a extend part at the center that would fit into the donut hole, the first part (donut) would be made out of poor heat conductor, like phanolic or high temp circuit board or Teflon, the other part would be made out of Copper. When assembled you have a Copper center that can hold the heat of combustion but the outer donut will not allow the heat to travel by conduction to the cylinder walls or head ring as in a Norvel engine. The back of the copper disk should be covered with another piece of phanolic or Teflon to help insulate the center electrode. What you end up with is a stack of three disks. One disk (middle) has a nipple that fits into the combustion side disk. This nipple is flush with the internal first disk. No flexing would be allowed since the material could be thicker to allow for normal construction on a lathe.

Looking forward to your test results!

Kelly

RE: Substitute for Ether
 

Good evening all,

First test of B20 biodiesel is done. Results are less than great but encouraging and interesting.

First off, B20 biodiesel for those that don't know is 20% biodiesel mixed with 80% petroleum diesel. The biodiesel itself can be made from any variety of seed oils, used cooking oils, and/or animal fat or tallow. It is sold as being able to be used in any vehicle you would use regular pump diesel.

Next, I did a simple visual and touch comparison of the B20 biodiesel versus straight kerosene. Kerosene is water clear and has a light oily slippery feel. B20 biodiesel ( at least what I have ) is a light honey or maple syrup colour, obviously more viscous than straight kerosene and has a distinctivley more oily and slippery feel than kerosene. Unfortunetly I have no way of objectively testing the differences in lubricity between the two but subjectively the B20 biodiesel is quite obviously more "oily" than kerosene. I don't have a sample of regular diesel but I suspect it is about the same as B20 biodiesel. First observation is that a B20 biodiesel mix should require less added oil.

At this point I wasn't sure how to mix up the B20 biodiesel so I just chose a point and started.

All my tests are done with my 40 year old PAW 2.49CC DS diesel with venturi (no throttle). I do 3 runs of about 10 minutes (about 1.5 ouce of fuel) with each mix so that I can verify my own results from run to run and give me plenty of time to play with needle valve and compression. I use an Atomik remote temperature gauge with which I measure temperature on the back side of the cylinder (out of the propwash) just above the muffler ring. I use a starter unless other stated.

Test prop is a Kavan nylon 9x5

Ambient conditions: Temp 22 degrees C Humidity 72% Pressure 1020 Kpa

Test 1: 10% Amsoil Interceptor Synthetic oil 5% castor oil 2.5% Amsoil Cetane Boost 82.5% B20 Biodiesel

- no go, couldn't even get it pop. I could smell the distinct smell of burnt kerosene/diesel so it was getting close.
- when I mixed this up the mix stayed a bit cloudly almost like it wasn't completely going into solution.

Test 2: 5% ether 10% Amsoil Interceptor Synthetic oil 5% castor oil 2.5% Amsoil Cetane Boost 77.5% B20 Biodiesel

- as soon as I added the ether the mixture cleared up and returned to the light honey colour of the B20 biodiesel
- 3 flip choke on the venturi prime and it started up with the starter after opening the needle valve half a turn and increasing compression a 1/2 turn from previous known running settings.
- I even managed to flip start the engine and it didn't take a lot of work at that. If the engine had a bit better compression it might have been even easier. This was a hot restart. I suspect that from cold I would have had to work harder at a flip start.

- 8600 rpm temperature 200 to 210 degrees F

Test 3: 15% ether 10% Amsoil Interceptor Synthetic oil 5% castor oil 2.5% Amsoil Cetane Boost 67.5% B20 Biodiesel

- started more easily than the 5% mix
- 8700 rpm temperatur 195 to 205 degrees F
- still needed the 1/2 turn richer and more compression to start and re-start

other observations:

The needle valve and compression was quite sensitive with both mixes. After the engine started to run I had to continue to tweek the needle and compression as the engine warmed up. Once warmed up it was steady at those settings. Using higher percentage ether mixes I can normally start the engine with the starter at it's normal running settings and it will warm up and settle into a nice run.

The exhaust had a distinct "white smoke" tint to it, just enough to notice and the smell was a light not strong and not really "diesel like"

These mixes also ran quite oily. That is there seemed to be as much or more residual oil in the exhaust/over/on the engine as when I run a higher castor oil mix (25% to 30%) which for the most part has some black/dark brown colour but equally or more just a nice honey colour.

Out of curiosty I richened up some of the test runs to see how low the engine idle; not an idle as you would get with a throttle but a slobbering rich run, about 2800 rpm and reasonably steady but did require a bit more compression and when I leaned it out I had to back off the compression again. This was not suprising in light of my other observations.

Conclusions:

B20 biodiesel has potential but not on it's own but as mix with standard kerosene or ether or both. It is too viscous and won't easily ignite. We could probably use less oil in our fuel when using diesel or B20 biodiesel but what is ideal mix? Further testing will answer that to a better degree. Still to try is similar mixes of B20 biodiesel with higher % of Amsoil Cetane boost, 5% - 10% ??

As we have seen from Andy's and other results, a little bit of ether can go a long way. Those old 30% + mixes of ether certainly help with the hand flip start. Perhaps we won't find that optimum mix with ZERO % ether but we have found that fuel with small percentages are very usable and that is progress.

Anyone have any ideas on determing an objective measure of fuel mixes lubricity?

I wonder if we where to wrap the cylinder head in some fashion to reduce the cooling fin area if we might not see an improvement in less sensitive needle/compression adjustments. In other words retain more heat to aid in the engines ablity to run.

All in all very interesting and educational.

cheers, Graham

RE: Substitute for Ether
 

I think this is raw fuel. Probably the biodiesel portion of the mix. The extra oily running also points to this. I think running the engine hotter may improve burning of biodiesel fuel.

RE: Substitute for Ether
 

Kelly, Graham,

Wonderful input. We need MORE of this. Yeah, retirement,, I WISH. Long story but I can still run engines. Anyway, the fishing trip was a dud. Left early this AM only to find a heavy drizzle when we got there. So we thought we would sit it out. Two hours later, we gave up. By the time we got home, (1.5 hours) the *&%#@ rain stopped. So, just after lunch, I got busy.

Ran the mysterious, glow energized contra-pistons. That can be seen here. http://www.youtube.com/profile_videos?user=hopeso

The glow energized diesel didn't quite work out. The glow did NOT assist in a cold start, we still needed to overcompress to get the engine going. A large disappointment but it was fun making the device. I learned a lot from that, and I think that there might be a much better way to make a diesel head than we're accustomed to seeing.

If you look closely, you'll see that the element is gone in the flat CP. The plug burned out and I extracted the filament. I'll run this piece again and this will allow us to see if it was really the element that gave us a slightly better idle and acceleration.

But the interesting thing was how well the engine ran on glow with a turbo plug. Was it just increased compression? I faced down a stock button and while there WAS an improvement, it wasn't dramatic. This inspired me to finally make a proper turbo button.

But this IS a diesel forum.

Pictured is the device with the flat bottomed CP and the glow CP to the left.

Below that are four copper discs that have suffered serious failure, likely for the reasons Kelly describes. These were installed UNDER my standard diesel head. The head had been set from the last run on no ether. In that case, the CP was two washers worth, deeper into the carrier. The discs clearly took up this clearance to a degree as an instant start was accomplished on the no ether mix. However, as the engine warmed up, the CP had to be backed off. This would have been OK and may have allowed some sort of hot zone in the bottom disc but I went too far and had to cinch it down again. Then I went too far again and had to tweak it out again. It finally settled down and I had a very good run with power nearly on par with the ether mix. Idling was quite good and transition was slightly improved.

So I shut her down, let it cool completely and had a go at another cold start without touching the CP. Unfortunately, there was no start. No way, no how. Only over compressing would allow a start on no ether fuel. The copper discs didn't help at all. And with that much tweaking, the engine started to mis-behave. Setting the compression became erratic. Something had happened pretty quickly and a look revealed that the bottom three discs had fractured. Good thing I stopped because the bottom disc was in danger of falling into the engine. OK, at least we tried.

Kelly's suggestion that a hot spot on an insulated CP may be the answer. From .15 and up. the Norvels won't allow for a conventional CP because of the head design. That'll have to be tried on the .074 and the .06.

Good work Graham on the Biofuel. Here's a thought. Biofuel lubricates as well as burns. In your case you used a blend. How about the pure stuff and with that, you get all the lubricating you need all by itself. Now, we just need it to self ignite. As Kelly mentions and my own test on the Amsoil synthetic proved, these oils do seem to reduce the cetane rating and combustibility. But with the apparent very high cetane rating of pure biodiesel, why won't they just self ignite? Could it be that with the use of an electric starter, they will? Or maybe they will with just a bit of ether. Or lots of cetane booster. Or a little of both. Here we would have a mix that burns completely with NO oil exhaust residue. Now would THAT not just be the cat's whiskers.

RE: Substitute for Ether
 

For what it's worth, I just stumbled upon this :

"The addition of ignition improvers like IPN (Iso-propyl-nitrate) or Amyl-nitrate allows the engine to run at lower compression settings without loss in performance, and achieve higher rpm as well.
For racing, IPN may replace part of the ether, or even all of it, and the oil content may be much lower by adding extra kerosene. Beware: The engine then runs much hotter, is harder to adjust, and MTBF is greatly reduced.
Be warned: Engines are easily fried this way."

http://mvvs.nl/
click on "Diesel engines"
In the write-up about the MVVS .15 D

RE: Substitute for Ether
 

Hi Andy,

Beryllium copper may not fatigue under the stress but it's expensive.

RE: Substitute for Ether
 

Andy,

Now that was a wonderful set of tests! I’m impressed with how well the engine runs currently, on a No Ether Fuel.

If you take a close look at the copper disk it if very evident that a great deal of heat was concentrated on that first disk. The distortion is a good indicator as well as the coloration changes to this heating.

I think the thin disk idea is a looser, but it seems to show that a hotspot is a valid concept:

I have two ideas to present:

Idea #1

It occurred to me that your CP button is already terminally isolated from the side-walls of the head by the two o-rings.

How about putting a copper tip on your current CP. If you machined off about 0.200 inch from the tip of the CP and added an insulated tip of copper then you’d have a nice “hotspot”.

I think you need a copper disk about 0.150” thick and a 0.050” thick thermal insulator sandwiched between the copper disk and CP button for a starting point. The stack could be held together with one small screw from the backside. The thickness of the copper disk could be altered to affect the size of the “thermal flywheel” effect. If you see too much heating then this disk could be changed to a thinner disk and just reinstall the CP and turn it in a bit more for testing. You could make a set of disks going from 0.050” up in thickness to perhaps 0.300” thickness using steps of 0.050” per increment to evaluate the entire range.

Idea #2

Your CP with the glow plug installed has some very interesting possibilities.

Since you can now adjust the ignition timing of a glow engine with extreme ease, you now have an entirely new type of engine with many benefits.

First things to remember (a general review of known concepts but still worth mentioning):

The reason for using diesel is the fact that you can adjust the timing to match the required propeller of your desires. If you want to swing a large diameter prop for good 3D performance especially on our little ½ A motors then a diesel really pays good dividends. You can tailor the torque curve to your needs, which is really important, but not easily achieved with just a standard glow engine.

Now after watching your movie of the diesel engine using a glow plug and glow fuel I realized yet another application.

Now you have a hybrid glow/diesel engine: Well not really, just a glow engine that will burn what we are now trying to make a “No Ether Fuel”. The only catch is you need some methanol to keep the plug glowing. If you use Morgan’s Cool Power oil, it will mix methanol with (Coleman stove fuel, gasoline, kerosene, bio-diesel, BBQ lighter fluids etc together and hold it together). I have run a 50/50 mixture of methanol and Coleman fuel in my Tower .75 engine, if I could have been able to adjust the timing with a Glow plug/CP then I could swing a really big prop very slowly. Just the fact the Cool Power mixes these two is very nice. Now Amsoil Saber oil will not do this at all. I tried many times with no luck.

Okay, I hear some say “well it is not a diesel engine now”. Okay that maybe true, but what you’re after is the ability to adjust the timing to swing that big prop with a tiny little motor.

The good point to remember is now you don’t need any type of Cetane Booster, the mixture maybe closer to a normal glow mix allow for a better fuel metering match with your standard carb. The CR maybe less for starting since you use a glow plug for light off and the methanol will hold the glow.

It is very easy to find BBQ lighter fuel or Coleman fuel and Methanol is easy to, or just mix some of your glow fuel with Coleman fuel and add some Cool Power oil to make it mix and mount up that larger prop. You can adjust the Energy density of the fuel by increasing the heavy fuel content like Coleman allowing you to run increase flight time. Bio-diesel and Kerosene could be use too.

I have tried this methanol/ Coleman fuel in my gasser engine (Converted Ryobi engine) with the use of a glow plug adapter. It works fine, but fuel metering is affected as the alcohol content increases since Gas engines us a carb intended for gas, which requires a different fuel air ratio. Glow carbs are fitted to some Gas engines to help this matter, but since we are starting with a glow engine then it is a better fit. Needles will become more sensitive, but it works.

I summation: Your GlowPlug/CP idea has many uses and allows for very large selection of fuels and perhaps a much better idea than a pure diesel engine. This mixture will light off with a glow plug and still burn heavy fuels and with the use of your GlowPlug/CP idea the timing can now be adjusted as required for that large prop. Plus it runs really clean if you use only Cool Power oil. No expensive Cetane Booster are required which makes for a easy fuel to build. This then becomes a true Multi-Fuel engine.

Fantastic Work Andy!

The Gas engine guys want to rid themselves of heavy Magnetos or expensive ignition systems, but still want the fuel economy of a gas engine.

For more details about Gas to glow:

The Gas engine conversion Forum : gas fuel with glo plug no ignition

http://www.rcuniverse.com/forum/m_1267448/tm.htm

Looking forward to the next series of test.

Kelly