What are your thoughts on this? I can make a gallon of 0% nitro for a fourth of the price of regular 5% nitro fuel. Just methanol and castor oil. Is it worth it?

I have mixed my own fuel for many years with success. Mainly because I like to run big glow engines (moki / Mark 180 or 210). these are 30 or 35 cc glow engines and will burn over 2 ounces per minute. they run fine on 0 percent fuel, although I usually mix up 5% nitro. The small glow engines (e.g. OS .46) will also run on 5% but not as nice as 15%. For the big glow engines I can run a little less oil (15% instead of 18 or 20%) which also keeps the cost down. Oil and Nitro are the expensive bits in the mix.

I intending to make 0% nitro for a .46 OS 46AX ABL, as getting some nitro where I live is really complicated. Is this a bad idea?

After we run our top fuel hemi dragster we have to chance the oil, it looks like chocolate milk from the nitro contamination. I wonder if my glow 46 would run on it?[sm=eek.gif] Im willing to try it.

O.S. two-strokes tend to prefer 10% to 15% nitro to run at optimal efficiency. Super Tigre and Magnum/ASP are often mentioned as 2-strokes that run wonderfully on 0% or 5% nitro fuel. I fly a Magnum XLS .52A that loves 5% nitro fuel.

It might be possible to tune your .46 AX to run fairly well with 0% fuel if you use a really hot (O.S. A3, e.g.) glow plug, but I don't really know for sure.

I have been using home brewed 0% nitro fuel for many years without any problem in OS MAX 46 FX and TT PRO 46. 20% castor and 80% methanol. No problems whatsoever. The plugs that I use are OS #8 and OS A3.

Cheers

Your motor oil will not mix with nitro, however castor oils will. Thought many dragsters have used castor oil or castor motor oil mix?

Do it. Yes it is worth it. Needle adjustments will be more sensitive is all.

I don't want to give away my age but I've been mixing my own 20% castor zero nitro fuel for 50 years now and so far I've never found an engine that won't run perfectly well on it. Most engines can be modified to run even better by raising the compression but it's not really necessary. Take the advice given by others about using a hot plug but most are using these anyway even with nitro. If you're used to using fuel with a fair amount of nitro then the needles will seem more sensitive but this is mainly because the engine won't use fuel as fast (longer flights on the same size tank) so the needle needs to be wound in more for a proper tune and less movement is needed to go from rich to lean.

Don't use less than 20% castor with zero nitro because with the low fuel consumption it needs this amount to flow enough oil through the engine.

Thats excellent news. Could I ask to the ones who mix their own fuel with 0 nitro, at what altitudes are your fields? I ask this because my field is at 2600m, about 7800ft over sea level so that is gonna definitely drain some power from the engine as there is a considerable less amount of oxygen up here compared to sea level.

There's a whole forum on mixing your own fuel in the engines section.

Have a look.

Thats right, thanks I hadn't noticed.

I am at 700 ft with no experience at high altitude. No Nitro fuel works OK for me.

cool. is the nitro contamination unburned nitro or is it exhaust byproduct? also what kind of oil are we talking about? I always wondered why glow engines use castor instead of dinosaur oil. mebbe you could take your top fuel byproduct and mix in some alky and have a good glow fuel.

Car oils aren't used because they don't mix with methanol. A lot of synthetic oils used in 2 strokes like chainsaws or whatever don't mix either. Castor is the best lubricating oil of any to use in our engines.

see, now i learned something. thanks.

"is the nitro contamination unburned nitro or is it exhaust byproduct? also what kind of oil are we talking about? I always wondered why glow engines use castor instead of dinosaur oil. mebbe you could take your top fuel byproduct and mix in some alky and have a good glow fuel."



I was just kidding about the oil nitro thing. The reason it looks like chocolate milk is because it doesnt mix with the 70 weight motor oil . Top Fuelers are running so much fuel through the engine with some extremely open bottom end tolerances that a lot of unburned fuel blows by the rings into the crankcase. The fuel pump on one of these things puts out like 22 gallons a minute. When it is running it is a lot like a glow engine running rich with all the unburned fuel spitting out the exhaust into my face as we try to tune it for the track conditions. The most fun you can have with your nose burning and eyes watering that I can think of. Hope to run Indy next month. Jeffie

gotcha. i always thought it was fun to watch em timing the engine in the pits and then watch when they switched from alky to nitro and see the crowd run away crying, noses running and coughing. great fun. now on the other hand, you guys that do it all the time i can't believe you don't wear a respirator for that copule minutes tuning the engine. I always loved top fuelers.

Buy a glow engine, convert it to diesel and run it on biodiesel. You can make biodiesel with veg oil, methanol, and lye....very cheap.

I have never mixed my own fuel. I just brought a ST 4500 and want to start. Can you tell me what I will need? I also have a few Moki 2.10's so I'll probably use it for those also. Thanks.

You need methanol and oil. Methanol can be purchased at "speed" shops (go-kart, boats, dirt bikes, etc.) Oil must be compatible with methanol, so usually must be ordered on-line. I get mine from Morgan fuels. two gallons at a time. You can also use castor oil. But if you go to a store thay sells oil (such as motorcycle shop, lawn mower shop, etc.) it is unlikely that they sell oil that will work with methanol. At least that's what I have discovered here (St. Louis).

You can also add a few drops of food coloring to mek it easier to see. And I add a drop of armor-all as an anti-foam agent. Usual mix is 80% methanol and 20% oil. For the large displacement engines you have you can to to 85% methanol and 15% oil.

Diesel model engines don't run on pump diesel or its substitutes. They are not true diesels because they burn a homogenous fuel air mixture supplied by a carburetor instead of fuel injected directly into the cylinder after the compression stroke is finishing.

Model diesel fuel is a mixture of kerosene, ether, and castor oil and a small amount of amyl nitrate. Some of these ingredients are very hard for individuals to buy in the U.S. because they can be used as drugs (amyl nitrate) or are used to manufacture methampetamines (ether).
Commercial model diesel costs just as much or more than glow fuel does and if you think glow engines are messy and smelly, wait 'till you try diesel.