Randy,

I flew for a couple of days on strait pump diesel and cetane boost & oil. I used a torch to start the engine. It was great till I tried it at below 55* F. and then I got a dead stick. I had to be really carefull of the plastic carb parts.... Now they are a bit blistered and burned looking but still work fine
If you try it you only need abut 30-45 sec. of preheat and spread the heat down to the crank area so the fuel can voporize. Don't go much above your spit bubling.

I am now able to start my engine by hand on 5% ether. So I'm wondering if I could start on straight diesel now as well.

The trick I use to start low ether is to choke it alot and what that does is raise the compression by filling the combustion chamber with liquid diesel and then it starts but you have to keep choking it alot till it warms up. It works! Just be really carefull if using the electric starter. You have to be a little closer to hydraulic lock than is comfortable.

The other cool thing about low ether fuel is that it doesn't kick hard so you can use all four fingers on the prop at once. I have been doing this for a while on my 12x6 MAS and it hasn't wacked my fingers yet. (try at your own risk)

Hmmmm, my mention of castor and lean runs sparked a bit of interest.

As far as I know, correct me if you know different..... all commercial model diesel fuel uses castor as the lubricant. Why should that be ? The manufacturers of our diesel fuel are hooked on the smell of castor ? Nooooooo, I don't think so.

The model diesel can place high loads on some parts of the engine, which are already operating at high temperature and with a somewhat hit and miss lubrication method.

To save typing I will use the following.....

QUOTE

Now for the castor oil question. NO model diesel engine maker recommends anything but castor oil for lubricant. I must have written this topic up more than a hundred times: in magazine articles, replies to readers, and in SMALLnet:

Castor oil is the ONLY -- UNIQUE -- commonly-available lubricant which becomes MORE viscous with heat. And the place that this extra viscosity ("film strength" is another way of expressing that) is vitally needed is NOT between the piston and sleeve, but at the wrist pin.

The wrist pin area is CRITICAL in all model engines, because every erg of mechanical energy that the burning fuel transmits to the piston has to be transferred via the wrist pin. It's the most heavily-loaded part of the engine -- and almost the hottest, because of its location so close under the piston crown.

Yet the lubrication the wrist pin receives is almost accidental. There's no "free flowing" fuel/air mixture within the piston's "underside cup". And an oscillating bearing is the hardest kind to keep lubricated. Unlike rotary bearings, where lubricating films tend to remain in place and renew themselves, oscillating bearings squeeze their lubricant out.

UNQUOTE

There is more but that should suffice. The other site that strongly advocates the correct amount of castor is the Diesel Combat site that has been quoted before, these guys know what they are doing and have a wealth of experience.

So..... castor is GOOD, castor will protect our engines, if we are looking for a substitute then it has also got to be good. Castor would be my first choice - we KNOW it works - but it won't mix well, or at all with paraffin without ether being present. The hunt is on for a substitute that we can PROVE works well, long term. If we run non-ether fuels then the penalty seems to be that we need increased compression - maybe not a lot - but still more than with an ether based fuel... thus the wrist pin ( gudgeon pin in the UK ) is under even higher stress.

Chevy is doing remarkably well with his used sump oil. I am glad he reported back again 'cos I have been wondering how his engine was "bearing" up (pun not intended). It's nice to see that he has got a mix that is working and has seen some hours use.

I can easily revert to used sump oil as I run a diesel car, however I would prefer something a bit cleaner ! I also want a fuel mix that doesn't need a propane torch to heat the engine first.

Olive oil may or may not do what I want, until I give it several hours running I don't know.
However, the guy who used non-ether mixes with modified veggie oil years ago cautioned me.
He seems to remember reading somewhere that olive oil as a lubricant created more carbon and lacquer deposits.

Whoooooaaaa, doesn't that sound like castor ??? More carbon deposits and lacquer sound very similsr to me !

Stewart.... you mention olive oil being used as a substitute for castor during WW1, have you any info or know of any sites online with more information. I have been trying to find information on using olive oil as a lubricant but without any success.

Reg

Reg there is no need for a propane torch if you run 5% either or one can per gallon of JD starting fluid.

I have been doing a huge amount of flying since my first posting on my Black Brew. I'm loving it! I think I'm going to go out right now.

I still feel that the operating temps in my diesel aren't getting high enough to need the protection of cator oil. The wrist pins of automotive diesels have similar issues exept they DO have pressure lube flowing to them.

As far as the aurgument that commercial fuel suppliers use castor: I say that is just tradition and that there is not alot of science or new inovation going on with diesel fuels. One of the commercial suppliers told me I couldn't use pump diesel..... The commercial suppliers seem like long time hobbiests- not like Chevron or anything. PAW's haven't changed in 40 years. It doesn't seem like there has been much new inovation on fuels in 40 years either.

I have been told that all the old time spark engines ran with 90 wt mineral oil gasoline mixes.

By the way used engine oil has been filterd tens of thousands of times. If it isn't clean enough for a model airplane then you should have drained it out of your car a long time earlier!

Hi Randy,

Welcome aboard and many thanks for your comments. Especially thanks for the answer to, "why bother, kerosene is cheap and available". And about torching your engine to get it going on a low ether mix. Maybe not necessary. Just use a high ether prime and a half dozen prime runs should get you into the temperature range you need for a start. I use a prime mix of 50% oil and 50% ether.

About lubricating oils.

Much of my work with engines has been 1/2A. When you think of 1/2A, I think that naturally you think of Cox engines. Cox engines, (and only a few others) are unique in that the wrist pin isn't a pin at all but a ball socket. This ball socket is, what I call "shrouded". Shrouded by the piston. Another engine that has this shrouded issue is the VA engine, both the original split case and the latter MK2, which is a true and nearly only true, 1/2A ABC engine. The VA is unique in that the wrist pin is supported by a carrier that is threaded on the outside. This is then screwed into the threaded interior of the piston. You're given shims to apply on top of the carrier to adjust the length of the overall piston/rod assembly. You can see that you can make very fine adjustments to engine timing this way. This is likely why VA did it this way as both are primarily used in contest work, free flight and combat.

So what does this have to do with castor? Cox recommends that you use only their fuel for a good reason. It's an all castor formula. And VA also insists that you use an all castor fuel.

Cool Power is known to be a good fuel but it's an all synthetic and has only 18% oil. Yet I've been running it in Norvels for many years with perfect satisfaction. Excellent power, superior throttling and never a problem with rod wear.

BUT, use Cool Power in a Cox engine or a VA and your piston pin/socket wears out pretty quick. The issue with the shrouded pin/socket is that you get very little fresh lube circulating in this area. With a conventional wrist pin arrangement, on the down stroke, crankcase pressure tends to feed a little lube into the minute clearance between the pin and the piston. You have to have SOME clearance and all you need is a tiny amount for effective lubrication. In turn, this flow of lube allows some of that to work its way into the pin/rod interface. Picture a 1/2A doing 18K and you can see that a lot of fresh, circulating oil can happen.

So castor IS a superior lubricant, in my opinion, but not just because it protects against a lean run. I will concede though, that lean run protection was needed and put to good use on early technology engines using cast iron pistons and steel sleeves. These most often had tight fits that needed to be carefully wore in. In this case, where the piston and sleeve grew at the same rate with heat, a lean run could easily damage an engine before you managed to get on the throttle to save it. ABC style engines behave differently, as we all know. Having said that, and despite *****g the needle on many an older style engine, I can't recall ever "frying" an engine.

Many times, you hear that you should set your needle a little rich to prevent damage "if you got off a little too lean". This really IS good advice for freeflight and controline but during contest work, maximum power is the norm. So you risk frying an engine if you did get off with an overlean setting because you were stuck till the tank ran dry, the timer went off, or the engine seized. In that case, the unique characteristics of castor serves us well. But what the hell, most times we DO have a throttle and can save the engine before we ever hurt it.

In my dabbling with oils and fuels, I have REALLY bashed this poor, old Norvel .15. So far, only the rod bearing surfaces have seen any wear. Wear so bad in fact, that on one run the wrist pin actually suffered galling. But the piston/cylinder assembly is just fine with good compression seal still evident. The crank to case clearances have also held up well although by now, a bit of slop had prompted me to install brass bushing.

The brand/quality/grade of castor is important. Most everyone, except me, just knew that kerosene won't blend with castor without the help of ether. Well, Klotz's Benol will,, as long as the temperatures are reasonable. Last year I decided to simplify fuel mixing by making up a no ether mix with the percentages adjusted so that adding just this much ether gave me the exact percentages I wanted in the final mix. That strategy simply worked, I had no idea that it shouldn't.

I suspect that in most cases, we don't really NEED the superior qualities of an all castor mix. Especially, I think, in modern, ABC style diesels. On the other hand, back a while I spoke with a rep from Klotz. A right nice fellow and naturally, he thinks that Klotz makes the absolute best oil in the universe. He laid claim that their all synthetic is all you need and in fact you can run oil fuel ratios as low as twenty or thirty to one. I would dearly love to be hired by Klotz to prove this. With engines provided by them, of course.

It sounds like the modified olive oil has some of the properties of castor and some of the properties of a synthetic. If that could be proved though, and if Klotz made such an animal, how hard would it be to convince enough people that olive oil,,, jeez, OLIVE OIL??? was something that they should try in their six thousand dollar dirt bike, or snow machine?

But you never know. Maybe Morgan Fuels is reading this right now and six months from now, they'll come out with a fuel that performs as well as a castor mix but with all of the desireable properties of a synthetic.

Today I ran a PAW .061 RC on my Black Brew after flying the .40 stick at the field for a while.

The PAW did start by hand but it was hard. It started great with the 1/2 A Sulivan starter but I managed to blunder and bent the rod a bit. I straitened it by hand and it ran fine again[8D]

Starting by hand on my brew was hard and you have to be realy carefull with the starter.

It ran great and idled well and then came back up to speed well. Unfortunately I didn' have my tach. with me.

Treven.

Today it was 5 degrees below zero with overcast and occasional flurries. No matter, I made a clamp to fit the Norvel .15 to simulate running at normal temperatures. First, a run was made with stock, 40/40/20 fuel to establish base settings for the CR and needle. The engine ran well with no sign of distress due to the temperature.

Next I tried to get a start on 100% Biodiesel. Tried and tried and tried. Using a 50/50 ether/oil prime, I got healthy, prolonged burst of 5 seconds or so many, many times but no go,, no matter what. It appeared that the engine WANTED to run but at a crucial moment, it ran out of ether fumes and quit. Next I added Amsoil cetane booster in increments from 1/2% to 4%. I got more prolonged prime bursts of up to 15 seconds but that was it.

Next to try was 20% kerosene and 80% Biodiesel. After much effort, I had a run. It took nearly a dozen, healthy, prime runs. The compression was turned out a small bit from the previous attempts. The needle was turned out a full 2 turns. But it was ROUGH. Then I added 1% Amsoil CB and we had a much smoother run. The needle was turned in a half turn and the compression screw out an eighth of a turn. Lots and lots of smoke, BUT the power was on par with a stock fuel as well as an all kero/castor fuel. The needle WAS turned out by a full one and a half but the power was there. So are we burning ANY Biodiesel? I suspect so and I'm hoping to do an exhaust oil collection test as soon as I can. Soon to be posted to YouTube, note how sensitive the compression was. At the end, I turned it in a bit producing a sag. Taking it back out brought up more power but then, a sudden flame out. This was typical. I'm speculating that poor atomization of the thicker mix is the culprit.

Somewhere it was speculated that MotoMaster's cetane booster was mostly Stoddard solvent. Pennzoil's Gas Mileage Improver has that listed as a prime ingredient so I tried some at 2% on an all kero/castor mix. Nope, something wrong. Didn't work. Notably, none of my calls to any of the manufacturers about their ingredients has ever prduced a response by phone or email. Maybe I'm wrong but I can't blame them for not wanting to elaborate too much about their products.

But, I just came cross these good folks.

http://www.renewablelube.com/

What do you know. It had to happen. They make a soy based, cetane booster along with veggie based lubricating oils.

I've emailed them for more information about the use of their products in our engines.

Yes, my own PAW .06 was also tolerant of non traditional fuels. Who would have thought? Neat.

And here,

http://www.freepatentsonline.com/4561862.html

we have someone who patented a unique diesel mix with alcohol and beta-nitroalkenes as cetane boosters.

Andy, are you saying it was 5 deg below F. not C.?? Wow, what happend to fall?? I'm not going to tell you the temps here

I can imagine if it was that cold that the biodiesel would be pretty viscous and not want to vaporize. You blocked the cooling fins but the crankcase was prabably really cold still so that wouldn't help vaporizatdddion.


I got my .061 PAW to run about 4,400 to 11,400 rpm on a 7x4 MAS. It would max out at 12K fully leaned but that didn't produce the best running.

Any body know the thrust of a 7x4 at 11K?

Morning,

Andy, is that Pennzoil mileage improver a Gumout Product? I haven't been able to find a MSDS for Pennzoil mileage improver or Gumout for that matter but I have found a couple for similar "cleaning and mileage improver" products. They seem to contain a lot of stuff other than Stoddard Solvent, for example xylene and acetone. Give WD40 a try, we know from it's msds that is primarily stoddarard solvent 60 to 100% in fact.

Interesting your comment on your biodiesel. In effect you made B80 biodiesel 80% biodiesel + 20 percent mineral diesel/kerosene. Your observations where almost exactly what I observed when I was using the B20 pump Biodiesel. There was a lot of oil coming out of the exhaust as it wasn't really burning all that well.

Interesting the link you provided to the company in Ohio marketing the soy based bio lubricants and fuel addivitives. I note that the cetane boost product is available in 1 gallon and larger quantities; that would be many life times supplies! (if it works).

I don't imagine our testing will convince any of the die hard F2C team race fliers to deviate much from their their fuel norms but it sure has been educational what with all the twists and turns this thread has taken. I note the comments regarding the modified Olive Oil and patiently wait for more test results and comments. I did a quick search of the net and wasn't able to find any reference to Olive oil being used as an engine lubricate; it might be there but I never found the right rock to look under.

I have another .15 size engine that I can use for some testing weather and time permitting. The old PAW's are still waiting their rebuild (winter project) .

cheers, Graham in Embrun near Ottawa Canada

I contacted Renewable Lube about their two stroke lubes a while back when I posted the link here. I didn't catch the cetane booster, probably because of the gallon purchase. The shipping on a quart of two stroke was more than the lube, so I never ordered.

Graham,
I did many hrs seaching for info on vegi oils(wished ied saved more of the info and links)
The only reason I can see to use soybean oil for makeing automotive lubricants is price, olive oil is wayyyyyyy more expensive. initial commercial tests with vegi oils used mineral oil additives with limited results. More recent tests/products are useing additives that have been specifically developed to get the best out of the base oil.
Now my reasons for modding the olive oil , I chat online to a bio chemist , I had told her of the priocess we had found to mod the cheap vegi oils , she confirmed this was the correct thing to do . Later I asked what vegi oil other than castor would make the best lubricant, without hesitation she said olive oil as thick as i can find, and also to increase the glycerine used in the modding process as olive oil is very low in saturated fats (the glycerine increases saturation level of the fats in the oil). Im no bio chemist but she is (she runs a gov lab with 15 other chemists/technitions) so i figured she was right. My test runs with the modded olive oil indicated the viscosity was suffient in the test motor (based on mechanical noise with both castor and olive oil lube)
But as I have said previously the required viscosity required for reliable opperation is engine dependent. I'm a motor mechanic and diesel fitter and am pretty good at identifying sources of mechanical noise and weather its normal or too harsh.
I can only say in the motor tested the olive oil was ok to use, the fuel blend was 20% oil 20% ether , 60% kero., the motor was hand started- started easily useing a normal prime technique, needle needed to be screwed in about 1/3 turn and compression down about 1/4turn from running regular old english mix.
Stewart

It's nice to know for sure that the process is correct. I guess the rest is trial and error to get the right viscosity.

Greg,
Ive only made the 1 batch of modded olive oil, next batch I will try an even greater quantity of glycerine as there was very little sediment after the simmering process( it was less than when useing the cheap blended vegi oil). The olive oil was noticeably thicker after modding, but not as thick as castor.
If previouse users of the modded cheap cooking oils have not experianced any undue wear , then I cannot see any problems with the olive oil.
When doing the modding , 1 must consider the overal cost of the olive oil and the amount of glycerine used , as the qty of glycerine goes up the added benefits will decrease, so an acceptable cost/performance must be decided on.
My test blend was on the short side of lube oil at 20% , but I did this to see if the viscosity was high enough - it seems to be. I didnt note any difference in the running temp or noise of the motor so I can only pressume the lubrication was adequate, only long term will tell if the gudgeon pin is suffering.
Stewart

There are quite a few glow fuels that are only synthetic. Some engine manufacturers recommend only synthetic. Why is there a need for castor in glow engines and not in gasoline engines which run hotter with less oil? If synthetic is OK for glow which run hotter, why not diesel? Many car, heli, and four stroke fuels are pure synthetic. YS says you can run full synthetic and they make the most power of any four stroke, certainly they are demanding of the lubricant. Diesel fuel costs enough, as it is, synthetic oils would raise the price. I'll concur that castor oil protects the engine from mistakes, but is it absolutely necessary?

People don't like to change. They like castor in their glow fuel, and the same kinds of things that perpetuated the ether requirement of diesel fuel push for the supposed need of castor oil. I haven't put a huge amount of time on synthetics in my diesels, but I'd take one of my NIB four stroke conversions and try it, because I'm 90% sure it works just fine, but I won't use an oil which doesn't publish it's properties. So far the only synthetic I trust is Klotz R50 and Maxima K2. Some lube manufacturers are very clear about the properties of their lubes, some are not. I contacted Redline about the viscosity of the two stroke oils and got a "yeah they are in that range" answer, so I won't be using their product.

What temperature does castor's viscosity begin to increase? What temperatures are actually attained within the engine?

This is a site I found searching for info on castor oil, have a look. http://www.groshea.com/caschemprodcats.html

I would think that if other vegetable oils can be processed to make good lubricants someone would be doing it. The only one that I know of is Renewable Lube, and they aren't that popular because I had never heard of it until it came up in a google search.

Yes cost is a consideration. I have not analyzed cost of making a lube, but I can't imagine it will be cheaper than buying a quart of castor or synthetic off the shelf if you factor in time. Time is important to me, usually if I can buy it, it's cheaper to me. If it can't be purchased easily and there are other benefits making it is better. I wish I had access to a viscometer.

I have to say that a huge thread about DIESEL FUEL and ETHER that pertain only to DIESEL ENGINES best belongs in the DIESEL foum IMO. I think it is ashame to bury it here where 99.9% of the stuff is GLOW or GAS related. The poor diesel forum is slow enough without this thread there will be very little reason to check it more than once a week or so. I wouldn't have ever found this thread here.

Treven

Perhaps all of the traffic noted in the Everything Diesel forum has attracted their attention and the RC Fuels forum having even less traffic is their way of trying to spread the traffic around. (ie advertisters)

In which case I think they should also change the title of the Everything Diesel forum to Almost Everything Diesel.


cheers, Graham

Yes, because fuel isn't a very important part of Diesel engines

Maybe the commercial suppliers who get $27 a gallon are getting worried?

No testing today. We looked after our grandchildren, twins a boy and a girl just 1 year old. It will probably take several days to recover !

Thanks for the comments Stewart, interesting to note that a bio-chemist advocated olive oil as a substitue for castor and also that the "modification process" is valid.

Why try to find a vegetable oil substitute ? I did a round trip of some 80 miles yesterday to my "local" hobby shop to find that the litre of castor oil I ordered had not been delivered to them !

I can order online but the postage costs bump the price up considerably. I will try a local pharmacy and see if I can get some there.

It is much easier to pop into the local supermarkey and get the olive oil and the ingredients for modifying it straight off the shelf, and it will work out somewhat cheaper as well. I had looked at 2 stroke oils and apart from high cost for a good oil I had no way of determining what an oil had in the way of additives... some mineral oils will cause combustion problems when used in our engines.

I hope to get some testing in but the weather is forecast for rain for the next few days, I will try if I get a break in the rain. In order to facilitate testing of the fuel using olive oil as a lubricant I have made a good size tank out of an old yeast container. This has a push on lid which I can remove to fill the tank while the engine is still running. This way I should be able to put a lot of running time onto the engine with minimum messing about.

Chevy..... your comments about the used oil being well filtered are spot on. My car is going in for an oil change shortly and I may keep the drained oil in case of future need ! I am impressed with the success you are having with your fuel mix. If I was tempted to follow suit, or even if I use non-ether mixes regularly, I would look at a method of easy starting. What about another small fuel tank with a Y connection to the the main fuel feed line and a way of stopping flow from the small tank ? This way the small tank could be filled with an ordinary 30% ether fuel mix, this could be used for starting (hand starting if you prefer) once the engine has run for a few seconds it should then be hot enough to turn off the small tank and let the engine then run on the non-ether mix... saves doing a number of primes and short bursts to get the engine hot....

I remember from years ago fishing boat and tractor engines which ran on TVO... tractor vapourising oil... which I assume was kerosene. The engine was started from a tank containing petrol. Once warmed up and running well the fuel line was switched from the petrol tank to the tank containing the TVO. This method gave easy starting and the ability to then run on a more economical fuel.

A scout around the web shows that there are a number of companys around the world doing research on veggie oil lubricants. They are looking to take advantage of declining oil resources and steadily increasing prices as the oil runs out. There is a site in India which mentions research into coconut oil.... Andy may be just behind them in research

I reckon that over the next few years we will be seeing far more about the use of various vegetable oils and additives for engine lubrication.

I also reckon this series of posts belongs in the diesel forum, if necessary copied to this one as well.

One last comment for Stewart...
I made a batch of olive oil using a 1/2 litre bottle of oil. I added 15 cc's of glycerine and there was a bit of sediment this time. I seem to remember you used 20cc's in a litre of olive oil and there was no sediment. My mix equates to 30cc's in a litre and this would seem to be too much if it is the glycerine dropping out as a sediment. My previous mix, using the same brand of oil but less glycerine didn't have any sediment.... seems like I may have found the limit ! The other thing that occurs to me.... with the cheap cooking oil there was quite a bit of sediment, yet using olive oil and more glycerine and washing up liquid gave no sediment suggesting that more glycerine is utilised when modifying the olive oil. The olive oil is using the glycerine more effectively ?

From what I can find online about olive oil it may be as well to use a cheaper oil. I have used virgin olive oil, which is the most expensive, whereas refined olive oil may well be as good for our purposes.
The virgin oil commands a higher price because of its superior taste. Not intending sucking the exhaust outlet I reckon a less superior taste and cheaper price would be better. The deciding factor will be if the viscosity is the same or not. If this oil works out on long term tests then it will be very nice not having the sticky deposit that castor leaves on everything. I noticed, when testing the olive oil mix a few days ago, that the exhaust was running pretty clean, the cheap veggie oil, and also castor, gave a black exhaust deposit.... the olive oil didn't seem to do this.

From my recent adventures trying to buy some castor I reckon the olive oil will work out cheaper than castor... even without taking into account my fuel costs or postage costs.... and that's if I continue to use only the best virgin olive oil.

Reg

Treven,

Hmmm, 27 dollars a gallon? I WISH. As I stated, five years ago it was 60 dollars, freight extra. Dave was embarrassed about it, (not his fault) so he gave me a sample to play with. Forever grateful to him, that sent me on my way to diesel heaven.

Sorry, no, that was 5 below Celsius. Just barely tolerable with the wind and snow and bloody cold on the hands when adjusting. Despite the cold, the fuel mix didn't seem all that "heavy". I suspect though, that warmer temps might not make much difference. Indoors, the mix is clearly much thicker than normal. I have a possible mechanical fix but that means major engine rework. That WILL happen but has been deferred to winter workshop time.

Graham,

Don't know about Gumout but I've given up trying to get any kind of useful information out of additive manufacturers. Again, I don't blame them but a shame. WD40 up next for sure. We''re not likely to alter anyone's fuel mixing strategies if they're engaged in serious contest work. We're just having fun dabblin" and discoverin" as GWB might say.

If you have a .15, I'd be most interested in how it performs in comparison to the Norvel. Reviewing some of the earlier runs on the Norvel .15, I note that even when using a stock, high ether mix, my power is down some 1000 RPM. Don't know what to make of that except that I'm now using a different carb with a smaller bore barrel. I'm going to stick with this setup to try and keep the later results more consistent. Try a 10 X 4 Grish on yours, let me know. They're not common, I can send you one if you like.

Greg,

Re Renewable Lube. Missed that, sorry. And what of a veggie cetane booster. How would THAT work? I emailed them and am waiting for that elusive response.

Stewart,

I'm going to try the veggie oil process soon, hopefully. But with a twist. Remember coconut oil? Highly saturated. Lots of oxygen too. See the link.

http://web.searca.org/elibrary/adss%..._biodiesel.pdf

They talk about using it as a 1% additive. Maybe a biodiesel additive that is superior to Amsoil cetane booster? Even at say 5% it'd still be affordable, I'm speculating. And how about a coconut oil lube?

I've emailed the authors and hope we get a reply. These folks have no direct commercial interest, it seems so we might get lucky.

Reg,

With the need for only 20% content, and with the hassles of getting/ordering/buying good castor, making your own lube oil looks better and better all the time. A guy could just take a weekend off to make up a gallon and be set for some five gallons worth of diesel fun. Just make it another part of this fascinating hobby. With the way the hobby is going these days, buy and fly, we have the distinction of making our own d*mn fuel, if you please.

So, we seem to be edging toward something TRULY radical. Biofuel lubricated with Bioil and supplemented with a Biocetanebooster. Geez, I feel like hugging a tree.

About viscosity. I'm not great on the molecular level so this may be a little bit off the mark but the reason I've got a thing for a no lube fuel is this. Kerosene has a low viscosity but some lube qualities. Ether has a VERY low viscosity and NO lube qualities, (I'm assuming). Put the two together at say, equal parts and what do you get? A very low viscosity solution with very low lubricating qualities. So to make up for that, you have to add a lube with substantial viscosity. So,, what if you have a good, clean, biodiesel fuel that is an oil, after all, to start with. It'll have considerable lubricating qualities I would think, despite the process to make it a fuel. After all, kerosene is also considered an oil as in fuel oil etc. So we have a viscosity problem with biodiesel. Would that be the ONLY issue? What if we found an additive that contributed to lowering the viscosity to that of a "normal" fuel? Yes, we've covered that ground but I'm just explaining my reasoning. This thread is very long and that answer might be somewhere but in a scattered form. Can anyone summarize?

The recent run of a no lube fuel with my own biodiesel and kerosene was an improvement over the ether/bio mix. A leaner setting, more power and less oil out of the exhaust. I won't try measuring the exhaust oil yet, not till I can see a dramatic improvement. Recent research has revealed that if you need to "wash" your biodiesel fuel, then your process is not the best. Even there, a wash can be OK but it should only be needed to be done at the most twice. I had to do it five times and I still had some cloudiness in the mix that never completely settled out. And a test of the Biodiesel I was given, (the ether mix) showed that it wasn't fully processed to the max as well. I'm going to try again to make up a more refined mix. Lots of time now, now that the weather has closed in. No heavy snow yet but bloody awful cold.

Andy,

IMO the reality is that 2 stokes need viscous oil to keep them alive. They always have. I don't think you can work around that. You can with a 4 stoke or a 2 stroke with a blower but then you have a compicated real engine.

Treven.

I had a chance to do some more testing with the olive oil lubricant today.

To recap... engine is a PAW 2.49, control line model with no silencer.

Fuel is 2parts of kerosene to 1 part of modified olive oil. This is then used to dilute a 30% ether mix down to 10%. There is 2.5% 0f "ignition improver" added. The ignition improver is based on 2-ethylhexyl nitrate and is available as a fuel additive for diesel cars.

First job was to run the engine on ordinary commercial 30% ether diesel fuel. I needed to do this to establish the compression and needle settings with "normal" fuel. I have run this engine on fuel with olive oil as a lubricant but not on normal diesel fuel since I originally bought it off E*ay.

When the settings were established and the tank run out I filled with my olive oil fuel mix as described above. The engine started easily with just a quick choke to get fuel to the carb and then a quick spin with the starter. The engine runs well on this mix although it revs up and down for 2 or 3 seconds until the temperature comes up, it then settles down to a steady run.

After changing to the olive oil mix I found the compression needed to be about a 1/4 turn more than with the 30% ether mix, the needle was not far from the same place, maybe a touch out. After a minute the compression could be backed off a bit more.

Next.... using the same olive oil fuel but with some more ignition improver added, this was a guess I just put a bit more in and didn't measure it. Would it make any difference ?

Yes it did... the compression could be backed off to just a bit more than when using the 30% ether mix.... looking good !

Last run of the day... I tipped a bit more ignition improver into the tank and crossed my fingers !

The engine again ran well and this time the compression was similar or very close to when using 30% ether

So where am I now ? Well, the engine is still intact and shows no discernible wear and is quiet when running... if you can call a PAW running flat out with no silencer quiet !!!

The ignition improver, which uses 2-ethylhexyl nitrate is definitely working and is offsetting the lower level of ether. I need to do it more scientifically now and measure the amount I add, I am thinking in terms of 10% initially.

PAW on their website state that 2-ethylhexyl nitrate can be used as a substitute for the isopropyl nitrate normally used in UK model diesel fuel.... so it is a recognised additive that is known to work. All you have to do is find the automotive diesel fuel additive that is based on it...[]


What have I achieved so far....
I have got a fuel with only 10% ether and using mostly olive oil as a lubricant running at nearly the same settings as a normal 30% ether mix. This would turn my 1 gallon of expensive commercial fuel into 3 gallons of a lot cheaper fuel. With the 10% ether content it should be no problem to use castor oil instead of olive oil and enjoy the bigger safety margin of using castor.

The engine emits plenty of oil but is far cleaner, no black exhaust deposits and easy to wash down.

I finally managed to trackdown some castor today after trying 2 pharmacies. I was surprised how viscous the stuff is, far more so than I expected. I can finally see what the stuff is like

Reg