Why glow fuel? What is it? Why doesnt it burn like normal gas does, there is always all that residue! And why stick with it, why not just use gas? If anyone can explain it and the history and background on it, I would greatly appreciate it..

all of the slime is from the 20% oil that our engines need because the conrod is bushed and dosen't have bearings. The bigger gassers have bearings and can use less oil. And second, gas motors produce less power than a glow motor of the same size, and they are heavy.

Glow is used because of it is simple uncomplicated operation, Light weight, very powerfull. Gas can't be used in a glow engine because it burns at a differant speed, does not react to the platnum glow plug the same as Glow fuel. would require an ignition system. Gas does not burn as clean.

Esanger,

Glow fuel is nitro methane and oil, some are made with synthetic oils some are castor and synthetic blends ,and the original was all castor,

it is used because the only way that a glow engine lubricates is from the residual oil, much the same way as a chainsaw does with 4 stroke oil, or a boat motor that requires mixed fuel,

If you have ever been to the drags those cars burn nitro, it burns at a very fast rate when compressed , and that in a glow motor amounts to the high rpms that these little motors produce.

on the other hand gasoline burns at a much slower rate, and requires the spark from a magneto or battey to continue burning ,

and fuel being suppied in much larger quanities to produce a very significantly reduced power per cycle than does glow fuel.

the advantages of gas over glow fuel is cost ,,,,,, a much longer stroke in the engine , making it possible to swing a much bigger prop.

the advantages of glow fuel are , less weight both in fuel and engine , a much higher rpm range , and smaller engine size making it much more versatile in plane size.

Hope this helps a little .

Correction to above, glow fuel is METHANOL and oil, with a percentage of nitro-methane mixed in from 0% to about 30%.

Opps , your right, Mtthomps ,thanks for the correction.

Highlander

Some more pro's for gasoline:

• more flight time for the same size fuel tank. (power at a MUCH lower RPM, so fuel lasts longer)
• More realistic sound.
• No oily residue to clean off the plane.
• Less field equipment - no starter or battery to lug around if you flip-start by hand.
• Less affected temperature changes.

Theres pros and cons for both, with the invention of small cheap(ish) cdi ignitions there is no reason you cant convert a glow engine to 2 stroke gas and it's quite popular to do so in some types of competition flying.
But there are other considerations such as some of the plastics and coverings that are used have been developed with glow fuel in mind and will deteriorate real quick with 2 stroke gas.
Runing 2 stroke gas tends to make the motor run hotter (due to the less lube) and some motors need a "special" liner and/or piston, with the electrics of the gas engine there are more problems with moisture.

So its realy horses for courses

Glow fuel, even zero nitro, has several advantages over gas. It only needs a glow plug for ignition, it produces more HP and gives the engine far more internal cooling. A downside is much higher fuel consumption and higher cost than gas.

Try gasoline in your glow engine. IF it starts, it'll quit as soon as you remove the glow plug igniter. Gasoline burns much cooler than glow fuel and will snuff out the glow plug.

That's not quite right, gas just doesn't react with the glow plug coil to keep it red hot. Only methanol can do that.

Gas in fact liberates more heat per pound than methanol does but when you have the correct mixture then you're burning a lot more methanol. That's where it gives the extra HP and the extra fuel consumption.

Amazing how many accurate and inaccurate responses are posted in this response. Some are just downright silly...

Glow Fuel: Accept it or buy a larger airplane that can be flown with an expensive gas engine or try electric.

The history is that modelers in the 1930s and 40s flew ignition gas engines which were not reliable due to having to use spark points and having poor batteries compared to today. They did not have electronic ignition modules. And small planes were difficult to fly as they had to carry a coil, condenser and battery pack for the ignition system. With the advent of Ray Arden's invention of the glow plug all of the onboard ignition gear was tossed out and no one had to adjust timing to get an engine to run. This invention liberated the hobby and is one of the handful of great advances in model plane flying. But as old modelers will tell you, the downside then was that their planes fell apart as the glues, dopes and plastic tanks could not withstand the alcohol fuel. When these problems were solved no one looked back.

Dave Segal

Forgot to charge the ignitors last night and the starter battery is low and then came in and read this thread. Well why you all are discussing the merits gas and glow, To heck with it I think i am going to go flying anyway.

I am a little burned out on pylon practice and the screaming Nelsons so I,ll just grab the Kerswap old timer with the Rivers 2.49 diesel (thats a .15 to most of you) and the half pint bottle of some sweet smelling lamp oil spiked with some Amyl Nitrate for body and a pinch of either for flavor. At the field I won,t bother with a bunch of support gear just some rubber bands and perhaps a ESV for checking the flight batterys. So I will just squeeze in an ounce of the sweet brew, Open up the compression screw and flip a few times then screw the compression on down flip and she ticking over. But its hard to tell you see because without a muffler its quieter than many electrics. OK the launch and you know this thing goes up at a deck angle that will make the 3D fanatics envious. All because of that big old club that the little Rivers is so happy with.

Yup this is relaxing! and gas, glow or electric are not the only games in town. You know I don,t thank I am going to bother with charging the ignitors or starter tomorrow either.



John

Ok, who forgot to charge the CO2 tank?

(No, I don't fly CO2 powered RC, but I know it's been done)

Oooooo...nice engine if it's one of the originals Some day I'll have to get some diesel fuel and try out my ETA Elite.

Its a Mk11 Silver Streak tuned version that I purchased new from the old Reginald Denny hobby shop in Hollywood about 1961 and how they happened to have it I,ve no idea.

Originally I used it in a variety of controlline ships and a couple of early rudder only RC ships and recently it has been living in the Kerswap with just a servo controlled pinch off for the fuel.

It is my only Diesel but has been my most delightful engine over the years of several hundred.

I am not familiar with your ETA but if you have not used it yet do get it in something you,ll probably not be sorry.

The ETA Elite is the engine that took over from the Oliver Tiger as engine of choice for team racing way back when. I got mine second hand so long ago I can't remember when! I've only ever put a few drops of fuel in it (borrowed some) and it's the only diesel I've ever felt that will give a kick just from turning the prop over

For a good explanation of glow plug function go to http://www.fly-imaa.org/imaa/hfarticles/engines.html and click on "glow plugs".

Dave Segal