Oils for use in diesel fuel
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I've seen the subject only touched on a few times, but I have wondered since Kerosene is petroleum based, what would be the repercussions of using a petroleum based oil in diesels? Castor is universal I know, just curious why petroleum oils aren't used. Anyone with some insight on this?
I'm fine using castor, but I've wondered if regular two-stroke oil for gasoline engines would work and if so any better than castor..?
I'm fine using castor, but I've wondered if regular two-stroke oil for gasoline engines would work and if so any better than castor..?
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Iseem to remember from long ago that a difference between petroleum and 'bean' oils could be observed by how they reacted on exposure to heat. Petroleum oils, on a metal plate heated from below, thinned and ran FROM a hot spot. In the same test, a 'bean' oil thinned and ran TOWARDS the hot spot.
There's also the idea that most automotive petroleum and synthetic oils may run at lower temperatures than we expose our oils to.
The only cooling we offer our oils is a combination of external air cooling and a chilling spray of fresh charge early in the compression stroke. Engines with an oil sump use it in part as a cooler for the load-bearing oil. We don't have that privilege.
In Dave Gierke's excellent series in Flying Models in the 1970's, he found a few results of interest to this query. Synthetic oils were fairly recent for us. Castor was nearly universal. Engines run hard and under high RPM and load often reached head & combustion chamber temperatures around 500°F. Castor oils can barely survive there; synthetic oils then available gave up at 10°F or more lower temperatures. Hope they've improved that since then... I
n any event, the tendency to flow towards a hotter area, and the quality of retaining ability to lubricate at elevated temperatures sound like positives for castor oil in our engines.
We've read excellent descriptions of the molecular differences between the oils made from recent plant products and "natural" or synthetic oils made from long dead dinosaurs. The molecular differences may explain it...
Sorry it got juggled around - thought I'd lost it from the thread, but it got in...
There's also the idea that most automotive petroleum and synthetic oils may run at lower temperatures than we expose our oils to.
The only cooling we offer our oils is a combination of external air cooling and a chilling spray of fresh charge early in the compression stroke. Engines with an oil sump use it in part as a cooler for the load-bearing oil. We don't have that privilege.
In Dave Gierke's excellent series in Flying Models in the 1970's, he found a few results of interest to this query. Synthetic oils were fairly recent for us. Castor was nearly universal. Engines run hard and under high RPM and load often reached head & combustion chamber temperatures around 500°F. Castor oils can barely survive there; synthetic oils then available gave up at 10°F or more lower temperatures. Hope they've improved that since then... I
n any event, the tendency to flow towards a hotter area, and the quality of retaining ability to lubricate at elevated temperatures sound like positives for castor oil in our engines.
We've read excellent descriptions of the molecular differences between the oils made from recent plant products and "natural" or synthetic oils made from long dead dinosaurs. The molecular differences may explain it...
Sorry it got juggled around - thought I'd lost it from the thread, but it got in...
Last edited by Lou Crane; 11-23-2015 at 01:43 PM.
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Chris, Excellent! Thanks!
My first (successful) contact with diesels was in the USA in the late 1940's or very early 1950's, at about age 10 to 12. OK and McCoy .049 diesels first appeared. Both sold 'diesel' fuels, which worked quite well in their engines.
By the time I was noticing the content of model engine fuels, most. of course glows, castor had "long since" come to dominate - as you point out.
I do recall mention, in Model Aviation and Aeromodeller, of various other fuel oils, many being varieties of Castrol. I hadn't realized that many were petroleum-based. Thanks for filling that in.
Other item about castor oil - it apparently was a most desirable choice for WW1 aircraft engines, until -some time back then - a disastrous, wide spread castor bean crop failure occurred. Racing automobiles continued despite the cost increase.
At least one world-famous driver - Tazio Nuvolari - became seriously ill, possibly terminally, from years of breathing castor-vapor laden exhaust. Many WW1 pilots had complained of at least diarrhea from that exposure, too.
((edit: I don't know how the date order in these posts got scrambled. This one was written Tuesday AM, 24 November, US Mountain Time Zone...))
My first (successful) contact with diesels was in the USA in the late 1940's or very early 1950's, at about age 10 to 12. OK and McCoy .049 diesels first appeared. Both sold 'diesel' fuels, which worked quite well in their engines.
By the time I was noticing the content of model engine fuels, most. of course glows, castor had "long since" come to dominate - as you point out.
I do recall mention, in Model Aviation and Aeromodeller, of various other fuel oils, many being varieties of Castrol. I hadn't realized that many were petroleum-based. Thanks for filling that in.
Other item about castor oil - it apparently was a most desirable choice for WW1 aircraft engines, until -some time back then - a disastrous, wide spread castor bean crop failure occurred. Racing automobiles continued despite the cost increase.
At least one world-famous driver - Tazio Nuvolari - became seriously ill, possibly terminally, from years of breathing castor-vapor laden exhaust. Many WW1 pilots had complained of at least diarrhea from that exposure, too.
((edit: I don't know how the date order in these posts got scrambled. This one was written Tuesday AM, 24 November, US Mountain Time Zone...))
Last edited by Lou Crane; 11-24-2015 at 08:49 AM.
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Actually its only relatively recently that castor became 'universal' for fuels-regardless of type [by recently I'm referring to a period 'pre-synthetic' era....] and that wasn't until the glowplug era began in 1947. Why? For the simple reason that castor was the ONLY readily available oil that would mix with methanol-and no other reason. The fact that it turned out to be a vastly superior lubricant for model engine use was entirely coincidental-and an unexpected bonus! The use of castor in diesel fuels did not become commonplace until the mid to late 1950s-prior-and indeed well after that-many proprietary fuels used a mineral oil based lubricant. Castor was-and is still-a premium priced product-and it was not uncommon for fuel suppliers to offer two diesel fuel ranges-an 'economy' range blended with mineral oil-and a 'premium' range with a castor base. In the UK ED, Frog and Kielkraft did this-possibly Mercury as well....
Furthermore-castor and kerosene don't mix--at all (anybody doubting this is welcome to try the experiment!)-it is only the presence of ether that stabilises the 3 components into a homogeneous mixture. [I should qualify this statement by saying that STANDARD castor will not mix-many of the current types-such as Klotz Benol, have been chemically modified so are no longer standard castor-some of these will mix].....so castor would not have been a natural first choice for diesel fuel when commercial fuels were being developed-the exact opposite of the situation with glow fuels.
Actually mineral oils work quite well for most sport diesel uses-and have the advantage of being cheaper, creating less mess on the model, and less stickiness-and whilst they may thicken in storage-do not tend to set rock hard in an unattended motor like castor does. Scale modellers find mineral oil based diesel fuel an advantage as it does not attack the often fragile paint finishes used for realism on such models-especially of early aircraft which had doped finishes that do not reproduce well with modern two part paints such as epoxy and polyurethane.
Hard contest usage-such as team race-with its requirement for extreme needle settings and low oil content fuels may well dictate that castor (or some of the extremely exotic synthetic oils) is absolutely required-but for routine sport flying use mineral oils are quite adequate-provided (as with ANY fuel)-there is an adequate amount to begin with....in the past I've used Castrol 2-stroke oil, outboard motor oil, and chainsaw oil-in diesel fuel with no ill effects-nor any particular advantage other than economy. If you are in a position to make your own fuel, you have this choice-if you are stuck with commercial blends then you have little option but to accept what's on offer. AFAIK there are only about 3 commercial suppliers of diesel fuel in the US, two in the UK, one in NZ-and i have no idea what the situation is in Europe and Australia! You also have to think in the context of diesels being a tiny tiny proportion of IC model engine use worldwide-and the overall market rapidly reducing under the onslaught of electrics-so the demand is going going to reduce in the forseeable future.
ChrisM
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Furthermore-castor and kerosene don't mix--at all (anybody doubting this is welcome to try the experiment!)-it is only the presence of ether that stabilises the 3 components into a homogeneous mixture. [I should qualify this statement by saying that STANDARD castor will not mix-many of the current types-such as Klotz Benol, have been chemically modified so are no longer standard castor-some of these will mix].....so castor would not have been a natural first choice for diesel fuel when commercial fuels were being developed-the exact opposite of the situation with glow fuels.
Actually mineral oils work quite well for most sport diesel uses-and have the advantage of being cheaper, creating less mess on the model, and less stickiness-and whilst they may thicken in storage-do not tend to set rock hard in an unattended motor like castor does. Scale modellers find mineral oil based diesel fuel an advantage as it does not attack the often fragile paint finishes used for realism on such models-especially of early aircraft which had doped finishes that do not reproduce well with modern two part paints such as epoxy and polyurethane.
Hard contest usage-such as team race-with its requirement for extreme needle settings and low oil content fuels may well dictate that castor (or some of the extremely exotic synthetic oils) is absolutely required-but for routine sport flying use mineral oils are quite adequate-provided (as with ANY fuel)-there is an adequate amount to begin with....in the past I've used Castrol 2-stroke oil, outboard motor oil, and chainsaw oil-in diesel fuel with no ill effects-nor any particular advantage other than economy. If you are in a position to make your own fuel, you have this choice-if you are stuck with commercial blends then you have little option but to accept what's on offer. AFAIK there are only about 3 commercial suppliers of diesel fuel in the US, two in the UK, one in NZ-and i have no idea what the situation is in Europe and Australia! You also have to think in the context of diesels being a tiny tiny proportion of IC model engine use worldwide-and the overall market rapidly reducing under the onslaught of electrics-so the demand is going going to reduce in the forseeable future.
ChrisM
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Thanks for your input, fellas. If I were to try mineral oil in my fuel (I do mix my own), what is the best kind/viscosity to use? I've seen 70wt oil mentioned in other threads, but only in regard to vintage diesels such as the Drone and others of the era. Would a 2-cycle oil intended for air cooled gasoline engines fit the bill or would a heavier weight engine oil like the 70wt be more appropriate?
I saw outboard oil mentioned by you ffkiwi, would the air cooled variety be better suited since the engine temperature of a water cooler engine is lower?
I saw outboard oil mentioned by you ffkiwi, would the air cooled variety be better suited since the engine temperature of a water cooler engine is lower?
Last edited by 1QwkSport2.5r; 11-23-2015 at 03:31 PM.
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This is one area where I can't give you a definitive answer-since my experience using them is limited to the three examples i mentioned above-again I was running these in sport diesels, in a FF and vintage operating environment-so we're talking big props, lowish revs and relatively short runs. I would think your aircooled outboard oil would be a sensible place to start. I do recall having misgivings using the Castrol 2-stroke oil (I've still got the container out in the garage with about 200mls left in it-out of the original litre! Obviously I used 80% of it-so it can't have been that bad in practice!) as it seemed rather thin (certainly in comparison with castor)-but on reflection no thinner than many current synthetic oils-but in the regime I was operating in, there seemed to be no ill effects. Whether that would be the case in a contest situation running flat out on a small prop I couldn't say. In a C/L situation you can hear the motor harden up and 'go hard' if it overheats-you might not be so fortunate in an R/C model further away-and possibly at part throttle.
One thing is certain though-the oil viscosity will have some effect. I recall the chainsaw oil being thicker than the generic Castrol 2-stroke.....and chainsaws are usually operated under some of the most diificult conditions for a 2-stroke engine-poor cooling, very heavy loads-so I guessed the chainsaw oil would be a bit better for the job. FWIW I used it all-so for some reason I must have preferred it to the Castrol oil. [this was back in the mid to late 80s-I was a poor PhD student so my model flying was done on the cheap....as much as I could achieve it]
As a striking example of the viscosity effect-for nearly 20 years (1992-2010) I was the main organiser for the NZ FF World Cup events-held at Omarama in the SI. Supplying FAI fuel is one of the tasks you have to do as contest organiser-it is mandatory not optional. This was no big drama-for F1C it's simply 80:20 methanol:castor. Ca 2002 the FAI amended the rules to allow synthetic oil as well as castor.....so now I had to organise two types of FAI fuel (plus 25% nitro for F1J!)...but of course had no idea what the appropriate ratio of castor based vs synthetic based FAI fuel should be. I simply guessed and got 3/4 of the total castor with 1/4 the newly sanctioned synthetic blend-both still 80:20 as per the rules.
As it turned out-I very nearly ran out of the synthetic mix-all the F1C fliers wanted it-and nobody wanted the old style castor mix. When I enquired as to why-they all said it was 'better'.....further questioning elicited that they were getting about 1000rpm more on the synthetic blend-so no wonder they all wanted it. [this may well have been the first occasion the new fuel was used at international level-I'm pretty sure the rule change only came into effect in 2002-and our event was one of the first on the calendar] Since the two fuel mixes are exactly the same differing only in the type of lubricant not the proportion, I can only attribute the increased rpm to the 'thinner' fuel-in other words lower viscosity. I don't think you can claim that the synthetic oil was a better lubricant per se than the castor-but the mix would certainly have atomised better-and perhaps the resultant charge would have had less inertia.
Anyway-all I can suggest is you do a bit of experimentation-and that may pose a few problems unless you can source smallish amounts of oil for cheap-or as a sample. I do not think there is currently any comparative data out there regarding the use of mineral oil in modern diesels-and specifically in longer running R/C engines. There is some loss of rigour in any case-since to be truly systematic you would need to operate identical engines on the different fuel lubricant options-there is quite a lot of anecdotal evidence that using synthetic oil in an engine previously 'conditioned' to a castor lube can sometimes lead to a loss of performance...and realistically you'd need to run a number of tankfuls of each fuel type....and you'd ideally still want a control using castor and another with synthetic as a base reference....
Quite a lot of work-and again (in an R/C sense)-how applicable? Routine sport flying (10-20 minute flights, most of which is at part throttle) can hardly be compared to R/C pylon racing in terms of engine usage-nor with 3-D flying or R/C aerobatics-but if you want to embark on some serious testing-the field is wide open.....and the results will add considerably to our collective knowledge base. In any case-diesel fuel is expensive-compared to other types-so any research that potentially leads to a reduction in fuel cost, has to be worth doing...
ChrisM
'ffkiwi'
One thing is certain though-the oil viscosity will have some effect. I recall the chainsaw oil being thicker than the generic Castrol 2-stroke.....and chainsaws are usually operated under some of the most diificult conditions for a 2-stroke engine-poor cooling, very heavy loads-so I guessed the chainsaw oil would be a bit better for the job. FWIW I used it all-so for some reason I must have preferred it to the Castrol oil. [this was back in the mid to late 80s-I was a poor PhD student so my model flying was done on the cheap....as much as I could achieve it]
As a striking example of the viscosity effect-for nearly 20 years (1992-2010) I was the main organiser for the NZ FF World Cup events-held at Omarama in the SI. Supplying FAI fuel is one of the tasks you have to do as contest organiser-it is mandatory not optional. This was no big drama-for F1C it's simply 80:20 methanol:castor. Ca 2002 the FAI amended the rules to allow synthetic oil as well as castor.....so now I had to organise two types of FAI fuel (plus 25% nitro for F1J!)...but of course had no idea what the appropriate ratio of castor based vs synthetic based FAI fuel should be. I simply guessed and got 3/4 of the total castor with 1/4 the newly sanctioned synthetic blend-both still 80:20 as per the rules.
As it turned out-I very nearly ran out of the synthetic mix-all the F1C fliers wanted it-and nobody wanted the old style castor mix. When I enquired as to why-they all said it was 'better'.....further questioning elicited that they were getting about 1000rpm more on the synthetic blend-so no wonder they all wanted it. [this may well have been the first occasion the new fuel was used at international level-I'm pretty sure the rule change only came into effect in 2002-and our event was one of the first on the calendar] Since the two fuel mixes are exactly the same differing only in the type of lubricant not the proportion, I can only attribute the increased rpm to the 'thinner' fuel-in other words lower viscosity. I don't think you can claim that the synthetic oil was a better lubricant per se than the castor-but the mix would certainly have atomised better-and perhaps the resultant charge would have had less inertia.
Anyway-all I can suggest is you do a bit of experimentation-and that may pose a few problems unless you can source smallish amounts of oil for cheap-or as a sample. I do not think there is currently any comparative data out there regarding the use of mineral oil in modern diesels-and specifically in longer running R/C engines. There is some loss of rigour in any case-since to be truly systematic you would need to operate identical engines on the different fuel lubricant options-there is quite a lot of anecdotal evidence that using synthetic oil in an engine previously 'conditioned' to a castor lube can sometimes lead to a loss of performance...and realistically you'd need to run a number of tankfuls of each fuel type....and you'd ideally still want a control using castor and another with synthetic as a base reference....
Quite a lot of work-and again (in an R/C sense)-how applicable? Routine sport flying (10-20 minute flights, most of which is at part throttle) can hardly be compared to R/C pylon racing in terms of engine usage-nor with 3-D flying or R/C aerobatics-but if you want to embark on some serious testing-the field is wide open.....and the results will add considerably to our collective knowledge base. In any case-diesel fuel is expensive-compared to other types-so any research that potentially leads to a reduction in fuel cost, has to be worth doing...
ChrisM
'ffkiwi'
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Thanks for your input, fellas. If I were to try mineral oil in my fuel (I do mix my own), what is the best kind/viscosity to use? I've seen 70wt oil mentioned in other threads, but only in regard to vintage diesels such as the Drone and others of the era. Would a 2-cycle oil intended for air cooled gasoline engines fit the bill or would a heavier weight engine oil like the 70wt be more appropriate?
Add a touch more, up goes the comp!
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Chris M - thanks much for your added wisdom. My angle I'm looking at is possibly using a non-synthetic mineral (Dino) oil either on its own or in combination with castor to see what happens. Castor is roughly $30/gal shipped to my door from my last vendor. Mineral oil for 2-stroke gas engines is roughly $12/gal. I'm not really concerned with saving a few dollars so much as is it worth trying and possibly using long term in a possible cost cutting measure. Will using Dino oil risk damaging the engine any more than using castor? I suppose the viscosity card comes into play here. I'd be looking at using a 20% oil content minimum for some ABC/AAC type conversion diesels. I would still use castor oil in any lapped of bushing crankshaft engines.
Chris W - duly noted on the oil weight in relation to the CR. Perhaps this could be of use to thicken fuel using say regular 2-stroke oil?
Chris W - duly noted on the oil weight in relation to the CR. Perhaps this could be of use to thicken fuel using say regular 2-stroke oil?
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I found some good reading about 2-stroke oils. Good reading. It looks as though API-TC is the better oil to use in an air cooled higher performance realm as opposed to the normal TCW-3 offerings. http://www.sea-doo.net/the-late-grea...ebate/2015/04/
I'm still on the fence on whether I want to go down this avenue, but it's a road of learning a few things which is great IMO.
I'm still on the fence on whether I want to go down this avenue, but it's a road of learning a few things which is great IMO.
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Chris M - thanks much for your added wisdom. My angle I'm looking at is possibly using a non-synthetic mineral (Dino) oil either on its own or in combination with castor to see what happens. Castor is roughly $30/gal shipped to my door from my last vendor. Mineral oil for 2-stroke gas engines is roughly $12/gal. I'm not really concerned with saving a few dollars so much as is it worth trying and possibly using long term in a possible cost cutting measure. Will using Dino oil risk damaging the engine any more than using castor? I suppose the viscosity card comes into play here. I'd be looking at using a 20% oil content minimum for some ABC/AAC type conversion diesels. I would still use castor oil in any lapped of bushing crankshaft engines.
Chris W - duly noted on the oil weight in relation to the CR. Perhaps this could be of use to thicken fuel using say regular 2-stroke oil?
Chris W - duly noted on the oil weight in relation to the CR. Perhaps this could be of use to thicken fuel using say regular 2-stroke oil?
I think your angle is worth pursuing-diesel fuel is expensive simply because two of the three major components are expensive-ether and castor (or synthetic if that is the lube selected)-now there is no substitute for ether (in the role it plays in the fuel)-but the lubricant offers some possibility for reducing the cost-and the cost differential is quite striking. The only issue would be coming up with the best choice of mineral oil-and there is such a wide range available that it would be a near impossible task to determine the 'best' one (and every possibility that there might not be a 'best' one-just a suitable class and grade)-its a bit like soap-virtually any soap might clean your clothes-but an awful lot of testing might be required to determine the best one....!
The other thing to consider is we operate our engines in an environment unique to aeromodelling-no other two strokes use fuel with as much lubricant as we do (the model car people are running about half the lube level we do.....and look how often they wreck engines!)-and more conventional two strokes are running at 5% or even less....BUT they are running engines with white metal or race bearings, steel rods (usually) and frequently needle roller big and little ends. And one assumes that modern two stroke oil technology is centred around the requirements of this style of engine technology-in terms of formulation and additives. The latter may be EP enhancers, detergents, polarity modifiers etc etc-are they advantageous for model diesels? Probably not....and even less likely to be so at the levels of lubricant we use. I doubt they will have any negative effects in our engines-but they must certainly add to the cost of the basic product...but then you run into the problem of how much demand there is for a simple no additive two stroke oil of XXX? grade.....the old bugbear of supply and demand raises its head again...
So I venture to suggest that an ordinary or economy brand of two stroke mineral oil is likely to be the best compromise point for starting the investigation-then you need to decide what engine you're prepared to sacrifice. Ideally it should be one you can get still get spares for-in the event things do not go well, I would expect the effects to be most noticeable in the rod bearings to begin with as these are the most highly loaded.
We know mineral oil based diesel fuels were is widespread use historically-but at a period before R/C was mature-so extended engine runs of 10 -20 minutes would not be common-and typical running times in C/L models would have been 2-4 minutes at best-quite a lot shorter-plus there were no effective throttles on diesels back then (with a very few exceptions such as the Taplin Twin) so the effects of throttling would not have been considered. This is where the data is lacking-and the only way to find out is by actual testing.
Provided you keep the oil levels up to what is considered normal (20-25%) I see no major issues is going ahead....and I would personally be happy to use such a fuel in a bushing engine-after all that's certainly what people were doing in the 50s and 60s. Again whether things work out OK will depend a lot on your flying style and type of model. If your flying is vintage and sport radio I would have no reservations-if you're into pylon racing, I can see perhaps that you might discover the limitations....but is pylon racing any harder on the engine mechanically than diesel team racing? I simply don't know.....one is known for the frequency with which engines blow up (especially rods!), the other uses the most highly developed and exotic engine materials and runs as hard and as lean as it is possible to get...
ChrisM
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Here is how a model diesel engine machinist and enthusiast and in Holland makes his fuel. Lubricant is 50% castor oil 50% synthetic air cooled two stroke oil.
For myself, I have never bothered with two stroke oil in my diesel fuel. Where I am top grade two stroke oil costs more than castor oil.
https://www.youtube.com/watch?v=PKMVpklGt2c
For myself, I have never bothered with two stroke oil in my diesel fuel. Where I am top grade two stroke oil costs more than castor oil.
https://www.youtube.com/watch?v=PKMVpklGt2c
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Here is how a model diesel engine machinist and enthusiast and in Holland makes his fuel. Lubricant is 50% castor oil 50% synthetic air cooled two stroke oil.
For myself, I have never bothered with two stroke oil in my diesel fuel. Where I am top grade two stroke oil costs more than castor oil.
https://www.youtube.com/watch?v=PKMVpklGt2c
For myself, I have never bothered with two stroke oil in my diesel fuel. Where I am top grade two stroke oil costs more than castor oil.
https://www.youtube.com/watch?v=PKMVpklGt2c
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You fellas are really awesome. Thanks so much for posting your wisdom. Around here, good 2-stroke oil is on-par with the price of castor oil with some of the cheaper varieties being cheaper by half or so. I have one engine I could "sacrifice" though parts are hard to get for it. I might try a quart of fuel as a test, but I'm not sure I would do it full time since castor isn't that badly priced. I have a good base of info to go on, so I may do some testing next spring when it warms back up and the snow melts.
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I have used castor oil sold for cosmetic use (soap making) in my diesels and have been very impressed. I like it much more than he now withdrawn Castrol "M". It is pure and de-gummed.
With free shipping in the US this looks a good deal.
http://www.ebay.com/itm/CASTOR-OIL-G...8AAOSwpDdVbdiQ
With free shipping in the US this looks a good deal.
http://www.ebay.com/itm/CASTOR-OIL-G...8AAOSwpDdVbdiQ
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I have used castor oil sold for cosmetic use (soap making) in my diesels and have been very impresosed. I like it much more than he now withdrawn Castrol "M". It is pure and de-gummed.
With free shipping in the US this looks a good deal.
http://www.ebay.com/itm/CASTOR-OIL-G...8AAOSwpDdVbdiQ
With free shipping in the US this looks a good deal.
http://www.ebay.com/itm/CASTOR-OIL-G...8AAOSwpDdVbdiQ
Last edited by 1QwkSport2.5r; 11-24-2015 at 07:37 PM.
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This has nothing really to do with oil specifically, but really my question pertains to needle settings/fuel mixture. Do diesels suffer from the same issue with the air temp having a large effect on fuel mixture from one day to the next (like 80F today to 40F tomorrow)?
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This has nothing really to do with oil specifically, but really my question pertains to needle settings/fuel mixture. Do diesels suffer from the same issue with the air temp having a large effect on fuel mixture from one day to the next (like 80F today to 40F tomorrow)?
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The high zinc stuff is supposed to be a lot better in full size diesels, no clue how it would do in a model diesel. Probably fine I suppose, but it would make the fuel awfully thick.
My question still bequeaths me - are diesels as sensitive to needle settings as glow engines with temp/humidity changes? Could I in theory run on my last settings when it was 50F in say 30F and not need to worry about compression and needle settings? Or would I want to start the engine a few clicks richer than the previous run setting and re-set compression?
My question still bequeaths me - are diesels as sensitive to needle settings as glow engines with temp/humidity changes? Could I in theory run on my last settings when it was 50F in say 30F and not need to worry about compression and needle settings? Or would I want to start the engine a few clicks richer than the previous run setting and re-set compression?
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The way Zinc protects high duty valve trains sounds interesting
The same high loads are in our diesels
For a glow no , the zinc might foul a glowplug motor ( element )
The same high loads are in our diesels
For a glow no , the zinc might foul a glowplug motor ( element )
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Saying that about mineral oil
I would only use castor
as its a traditional as flying a 1.5
If its not the whole thing I dont like it
The mess
Fuel soaked plane
The blood
The chewed up engine
and the terrible mess when my friends crash my plane
I would only use castor
as its a traditional as flying a 1.5
If its not the whole thing I dont like it
The mess
Fuel soaked plane
The blood
The chewed up engine
and the terrible mess when my friends crash my plane
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What happens is that the plate was coated with castor oil in the fist place (as in it was originally there) and lingered through polymerisation in a different lacquer based form.
Not that a wet section had flow towards a hot dry section, but castor is more polar and is attracted to metal more than any other oil and will stay put for longer.