RE: gas fuel with glo plug no ignition
 

Av8tor1977,
As I previously said, the runs with the OS 60 would only point in a direction and may not be directly applicable. This was more a "proof of concept" than anything else. There is no question that going down in oil content will have an effect on the performance and intuitively I would say that the idle would be improved. However, I'm not sure that I would go much lower than 50:1 on oil. Gasoline( even without the oil added) has a certain amount of lubricity while methanol has none.

We have a large group of avid combat flyers in our club and they buy methanol from a distributor. Last price was $2.63/gal in 55 gal drums. I just borrowed a quart from one of them.

You can get ether by using diesel starter fluid(John Deer seems to be preferred by the diesel guys). Adding ether was the subject of discussion in one of the topics in the "Everything Diesel" forum. Basically what they do is glue a 1/8" tube into the spray nozzle of the starter fluid can and connect it to a jar with a tube going down to the bottom. The lid of the jar has a vent. They then bubble the ether through the Kerosene/oil intermittently, allowing the bubbles to go down and the propellant to vent until the mixture volume comes up to a mark on the jar. After thinking about it for a while, I believe that ether would be a much better ignition aid than acetone. However the ether content would have to be determined carefully for, I suspect that you might get into pre-ignition(detonation) problems if the content was too high. Most of the diesel fuels run 1:1:1 castor oil, kerosene and ether respectively. Some use amyl nitrate and/or MEK peroxide(Catalyst for Bondo) as an ignition aide. Since the ether/oxygen reaction is more readilly catalized by platinum than by compression, detonation could be a problem.

If you want to try ethanol, just get some denatured alcohol from a paint store. It is ethanol with about 1% methanol added to make it non drinkable.

RE: gas fuel with glo plug no ignition
 

Ok, this has been pretty interesting. Has anyone tried the E85 blend (85% ethanol and 15% gas) fuel? Some new car mfg's are selling E85 compatible vehicles. Of course there are not ANY E85 refueling stations near me!

RE: gas fuel with glo plug no ignition
 

I've been following this disscussion with interest. I have an OS .90 four stroke that I was planning to convert to ignition and gas but if it can be done with glo, all the better. However, I'm not sure about lubrication. One of the main reasons for going to gas is because of the gunk that methanol, or rather the castor oil, leaves on the aircraft. If gas is used and 20% methanol could two stroke oil be used at say 25:1 or would this damage the engine?

RE: gas fuel with glo plug no ignition
 

I have a customer who runs an OS surpass on ignition..He has about 250 hours on the engine...He mixes his own fuel...He runs 10% synthetic oil..The bushing con rod needs the same oil ratio no matter what fuel is used..He gets away with 10% because he just flies around at 1/2 throttle most of the time...

RE: gas fuel with glo plug no ignition
 

RCIGN1 is absolutely correct about the oil content for four strokes. I have a Magnum 80 on ignition and gasoline that has about 50 hours on it with no problems on 15% synthetic oil. However, the glow engine carb setup is for metering methanol at a 6.5 air to fuel ratio. On gasoline, even with 20 to 25 % methanol, the needle settings between rich and lean are usually less than 1/4 turn. It is really sensitive. However you can take a spare needle and modify it to give you more adjustment latitude. The mod is shown in the attached drawing.

RE: gas fuel with glo plug no ignition
 

The SuperTigre carbs already have a loooong taper, should work well with gasoline, or maybe the thread size on the needle would be the same...Harry Higley used to sell SuperTigre replacemant needles...the needles were quite long and tended to vibrate open..We cut the needle close to the carb and soldered on a 4-40 nut..

RE: gas fuel with glo plug no ignition
 

Ok guys this is getting better every time, thanks. It rained this weekend so I didn't get a chance to try my weede with all the possible combinations, being a chemist by profession
I have some anhydrous ethyl ether, I will give it a try in a 5% mixture and include it on my table and see how it turns out, so to summarize the mixtures to be tried they will be as follows:
a.- Gasoline + oil (synthetic) 50:1 ratio.
b.-Gasoline 90%, methanol 10%, oil in a 50:1 ratio
c.- Gasoline 85%, methanol 15%, oil in a 50:1 ratio
d.- Gasoline85%, methanol 10%, Acetone 5%, oil in a50:1 ratio
e.- Gasoline 80%, metanol 15%, Acetone 5%, oil in a 50:1 ratio
f.- Gasoline 95%, ether 5%, oil in a 50:1 ratio
g.- Gasoline 85%, Methanol 10%, ether 5%, oil in a 50:1 ratio
h.- Gasoline 80%, methanol 15%, ether 5%, oil 50:1 ratio

I will develop a table for the fueld used vs the rpm's obtained, being that I live by the beach this readings will be at sea level and I wil be using a weedeater 18 cc engine with a 15x6 or maybe a 14x6 master airscrew prop.
Until then I will keep in touch hopeing that the weather conditions for this weekend are favorable, thank you all for your valuable information and lets see if something good comes out of this.

RE: gas fuel with glo plug no ignition
 

GO GO GO...

Great plan, and I can't wait to see the results. Thanks in advance!!

AV8TOR

RE: gas fuel with glo plug no ignition
 

Did anybody read the engine column in the new AMA Model Aviation??? Run your glow engine with 20% water and gain power.
Water most places is cheaper than gas:)

RE: gas fuel with glo plug no ignition
 

but wath does it realy means by running with water, glo fuel + 20% water? could it be done with gasoline? don't thionk so.

RE: gas fuel with glo plug no ignition
 

Actually years ago they made add on water injector systems for cars. It was supposed to give you more power and cooler running engine. I never bought one so I don't really know how well it worked. The information as I recall talked about a very fine mist injected in the carb throat. I have been thinking about when I get some time trying to build a system to try on a conversion engine. I think it might be interesting or it could turn out to be more work than it's worth, I don't know. Just my 2 cents worth of opinion. Ron

RE: gas fuel with glo plug no ignition
 

Hi,

I haven't seen the AMA article, so I can't comment on that. But I do know a little about water injection. The water, or water/alcohol injection, was first used I believe, on the World War Two fighters. It is used to combat detonation in engines with high compression ratios and/or being run with a gasoline of lesser quality octane rating than needed. You are right, it was offered and used for car engines for a time as well. The older cars were designed with higher compression ratios, and when the fuel quality started declining in the beginning of the "smog years", the water injection systems would sometimes help the situation.

Detonation is generally more of a problem in, as I said, high compression engines, and also in engines with large bores. Our little weedie engines have both small bores, and low compression ratios, so detonation is not a problem, even with today's crappy gasoline. Water &/or water/alcohol injection would probably be a waste of time and gain nothing. One interesting side note however, is that the engines run with the injection showed remarkably clean combustion chambers and piston tops, with virtually no carbon build up.

Hey aero nut, any luck with your tests yet????

Hope this helps,
AV8TOR

RE: gas fuel with glo plug no ignition
 

yeah, one of the 240Z i bought had a "suck through the carb" turbo with water injection... i even worked out a "stoplights per gallon of water" ratio until i finally replaced it wth an electromotive fuel injection system and intercooler...MUCH MORE POWER!!! no Z's to be found over here but i'm close to bringing one over...


dave

RE: gas fuel with glo plug no ignition
 

This is what I was thinking of. The gas/oil would tend to foul the glow-plug. Maybe the steam cleaner effect would help keep it cleaner

RE: gas fuel with glo plug no ignition
 

Thank you very much for your interest and support av8tor1977, I haven't had a chance to do the experiments do to the fact that I was out of town for thanksgiving holidays, so I planned on doing it this weekend but guess what? it rained again so I haven't been able to do so. I will make sure to let you know my results once I can fulfill this task, I am as eager and pumped as you are to find out these results because I am sure we can probably get something useful out this.
By the way, has anybody tried anything on this subject with their gas engines just for curiosity? please don't let this subject die lets keep trying and find out more results and answers from other R/C brothers.

RE: gas fuel with glo plug no ignition
 

Water does not mix with gasoline..ANY water is a gasser carb will cause immediate stopping of the engine since water does not burn..A few years ago at a race someone sabotaged on of the engines by putting water in the gas..When we took the carb apart there was a one drop of water in the chamber....Engine would not even start....

RE: gas fuel with glo plug no ignition
 

Yep water wont mix with gas, so one drop will plug a jet. But water will mix with glow fuel.

RE: gas fuel with glo plug no ignition
 

To what result??

AV8TOR

RE: gas fuel with glo plug no ignition
 

More Power, cheaper fuel. The article said 20% water and the engine would still run and made more power.

RE: gas fuel with glo plug no ignition
 

Why not run 50% and get WAY more power ?
Hey TK, ever touch a spark plug with your tongue and flip the engine over ? :eek:

RE: gas fuel with glo plug no ignition
 

Antslake,

You can get the water out by putting the jug in the freezer! The water (if any) will freeze out and form ice on the bottom first, and the water free fuel can then be poured out.

RE: gas fuel with glo plug no ignition
 

RC
I didn't write the store, its in the engine column in this month AMA mag. TO hard to get a good flip on the prop with your tounge on the plug lead, thats what OP fingers are for.[&:]

RE: gas fuel with glo plug no ignition
 

Hey, Kris^ said it was a good way to test for spark ...thought maybe he was on to something...:)

RE: gas fuel with glo plug no ignition
 

Half the snowblowers I used to get in to fix wouldn't start because of water in the gas. An ounce of alcohol in the tank would keep it in suspension and go through the engine. Those of you who own snowblowers, remember this trick.

RE: gas fuel with glo plug no ignition
 

AERONUT...

Good to hear back from you. I'm pretty busy with full size aviation and models on the side. I'm presently playing with a Kioritz 23.6cc hot rod engine that we are talking about in the thread Homelite 25 versus Kioritz 23.6. I am very interested in your results with the glow plug on gas idea however. If we could get this concept down to something workable, it would really be neat for the smaller end of this gas conversion area of our hobby. Good luck, and I look forward to seeing your results.

Thanks!
AV8TOR