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Engine basics => Engine set up tips => Topic started by: bob whitney on April 23, 2020, 09:51:07 AM
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too windy so fly this morning so did some fuel testing.
using a PAW .061 ,I ran my reg mix 20%oil 50/50,35%ether,45%Kar.2.5%DII. steady RPM was 10.950 7/4 prop
mixed up a new batch with 2%centane booster and no DII. the only diff should be at top end this should only affect top end if at all
it started fine ,had same 10.950 RPM and ran steady ran the tank out.
thinking I should mix up a batch with no C/B or DII and see what happens.when the wind lets up I will try the same thing in the 35 D in my Big Job
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Hello Bob:
I have using Amsoil CB at 2% with the same mix as you for many years. It works very well.
In the 80’s, I obtained all of the ether that I wanted for FREE. The good old days! Now, running a Diesel is not as much fun!
Be well,
Frank McCune
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god we could almost start a new post on the good old days as compared to today
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The stories would never end. And some of them might even be true. y1
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stuff we were given back in the 50's and 60's we cant even afford to buy today
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2.5 DII seems a little high to me. Are you jacking that up because of the small displacement?
McSlow
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NO S?P
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the diesel not being cowled in cools down once in the air .the extra DII lets it run a little harder so it do sent drop off
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the diesel not being cowled in cools down once in the air .the extra DII lets it run a little harder so it do sent drop off
Bob, you're giving away your secrets! ;D
DII == "heat in a can"
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Bob,
Interesting with the AMSOIL Cetane improver. From data sheets the main component is 2-Ethylhexyl nitrate (see attached excel file). This has an autoignition temp of 266F (130C). It seems to burn rather then detonate which allows higher percentage. Maybe could do high percent an no ether?
Best, DennisT
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Where do you get this stuff? ???
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Where do you get this stuff? ???
Many truck stops, as well as via Amazon.
Contrary to Bob's unique way of spelling "-) , Look for "Amsoil cetane boost"
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Bill, your job is never done. got mine at O'REILLY's H^^
Bill, on the bottle it is spelled AMS OIL wont let me spell it all together
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Bill, your job is never done. got mine at O'REILLY's H^^
Bill, on the bottle it is spelled AMS OIL wont let me spell it all together
Uncross your eyes, Bob! ::)
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Anhydrous Ether is available on Ebay. Expensive at close to $100/L. Makes ~ 3L of diesel fuel.
Is there a less expensive source?
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I've used an Aussie product called Diesel Fuel Booster made by local company Nulon. It is basically a Cetane booster, like the AMSOIL product, the active component being 2-ethylhexyl nitrate, at 10%-30%. This is the component we need which controls the ignition of our diesel fuel. Previously, when available, the 2% of so of ignition improver was Amyl Nitrate or Isopropyl Nitrate. (Any of those "Nitrates" seem to do the job, but most are now off the market thanks to the junkies). Without it, the engine can be prone to pre-ignite, so the DII smooths out the ignition of the Ether and prevents diesel-knock.
The remaining ingredients are glycol at >10% and Naptha Petroleum at >60%. So, whereas in the old days we used 1.5%-2% "straight" ignition improver, the products of today that contain the important ingredients are virtually all kerosene. If we were to use 2% of a product such as this (or the AMSOIL Cetane booster), then the actual active ingredient we want is at a total of only 0.6%, hardly enough to make any difference.
For those using these "truck" diesel Cetane boosters, can I ask, are you using 1.5%-2.5% of the entire product? I figured that if the Nitrate component needs to be at 1.5%-2.5%, then we need a whole lot higher % of the product in our fuel to add enough DII to make the difference needed.
So, I simply factored in the 70%-90% of the remaining ingredients as part of the kerosene, reducing the added kerosene proportionally. At this, I ended up with the correct % of the Nitrate product.
Having said all that, I'm only working through my own theory. I've tried it on several bench runs. Seems to run ok. In flight? I have no idea.
Hope I haven't baffled too many.
Rod.
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Mike,
One possible source for non-racing fuel is "Starting Fluid". In the spreadsheet I posted there is a sheet that list various brands of starting fluid and approximate % of ether. The best right now is John Deer Starting Fluid, it has 80%+ ether. Other brands will work, simple mix with brands that have at least 40% ether is to just mix it straight from the can with 25% oil (Klotz, castor or 40 SAE mineral oil). For fixed compression engines like the DRONE Diesel, mix the John Deer SF with the oil and go fly.
Best, DennisT
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We don't have the John Deere starting fluid out here, but I have found that "Master" (US brand) has %50 Ether, so considering most of the remainder is Petroleum Naptha, I plan to do as Denis suggested and mix it straight with oil.
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Olden,
How did you do with the starter fluid /oil mix? What % and kind of oil did you use? This has been done by others, just need to get SF that is fresh and has most of its ether in it. Might need to spike it with a bit of Amsoil or other cetane improver.
Best, DennisT
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Hi Dennis. Everything I have said about the starting fluid is pretty much speculative because I haven't run out of my previous mix of diesel fuel as yet. I had a guy find me some pure Ether a while back, at huge $$, so I mixed up 33% ether, 33% castor oil and the remainder in Jet-A1 plus the cetane improver (diesel booster) as mentioned in my previous calculations. This fuel seemed to start and run pretty well in the majority of my diesels on the bench. I just go on the traditional blend of 1/3 each component, although 33% oil is pretty heavy going and modern diesels regularly recommend 25%.
I have a can of the Master 50% Ether starting fluid and plan to test my theory once my existing fuel supply runs out.
On another note, I found an interesting clip of an OS FS-48 diesel which is started on standard Ether based fuel from an external tank, and once warm it is switched to the on-board tank containing Etherless fuel. Very interesting to see it running so nicely without Ether.
https://www.youtube.com/watch?v=0Mp0nmCRKHc