Hi,

So, cutting to the chase here, it sounds to me like a mixture of 50% E-85 if you can find it, 50% regular gas, and your normal oil mix would be a good way to go???? (My closest source for E-85 is over 200 miles away, so I'm wondering if cutting it like this will result in a good mixture. I also don't want to modify my carb for a higher alcohol mix.)

Aeronut: Did you get the pm I sent? Please e-mail me.

Thanks,
AV8TOR

Why not 50% gas mixed with 50% denatured alcohol? Isn't denatured alcohol the same as E85 with a small amount of methonol added to the denatured alcohol? They are both ethonol arn't they ?

I cant seem to get the denatured alchol to blend correctly. But I havent tried very many diferent type of oil.

What oils have you tried?

Get a spray can nozzle that has a tube on it, like carburator cleaner. Use that nozzle & tube on a can of Ether base starting fluid. Bubble a small quantity of the starting fluid into the Gas/Alcohol mix, it doesn't take much. It will all go into a stable solution and the Ether will help ignition.

just try 50%gasoline with 50% methanol it works wonders and you dont have to modify your carb, get better transition respose, better idle and even on regular ignition more power and rpm's, thats the mixture I am using right now the thing is to use an oil that will dissolve in either methanol or gasoline (Klotz will do) or use a 50/50 of synthetic oil with castor then blend into gas at your favorite gas/oil ratio (I use 50:1 ratio which amounts to about 2.6 oz per galon or 2% oil)

Al right, you convinced me. My second Poulan 25 is coming tomorrow so I will give it a try. Three questions:

1. Where do I get methanol. I mean what kind of place do I need to visit to get some. Some ideas who is selling this stuff (not by barrels) in Sacramento area?

2. What is that Klotz oil. I mean what is the full name, how the bottle looks like, and where do I get it on Sacramento area?

3. I know the place that is selling Amsoil. Will it work? The guy in ATV store said, that Amsoil can be mixed with everything, but does it dissolve in methanol?

RysiuM

For methanol try racing shops or look in the yellow pages under high performance fuels (drag racers use it)
as for the oil its Klotz Thecniplate oil they sell it in the motorcycle shops or you can try VP's castor oil, Maxima K99 (wich is a blend of castor oil with synthetic) or something like that etc. When I buy VP's castor I mix it 50% with 50% Amsoil and it works great with the fuel mixture.

There is a gas station that sold Methonal on Power Inn road, right accross from the Home depot.

I can't remember the street but it is at the first intersection when you get off Hwy. 50 headed South on Power in Road

It's the only station on the right side of the road at the intersection.

I saw the pump when I was getting gas.

I just came from there. There is a Shell (next to Home Depot) and CHevron (across the Folsom Blvd). I didn't see methanol there.

However I found the racing store on H-wy 99 and Grant Line. They have methanol 2.99 a gallon from the pump. I didn't have container with me, so I will get some tomorrow. Unfortunately they don't have Klotz. Just Redline for methanol but it doesn't mix with gas. So I'm still looking for the oil.

RysiuM

Ok, so I did the test. 50% gasoline (87) 50% methanol, 3% Castrol racing oil. It disolves nice in gasoline and methanol. Very clear solution.

First I tried to flip the engine, it blew away my glow adapter. My neighbours thought probably, that I shot someone.

I made another adapter with small step preventing from blowing it up. I run the engine. Tuned for maximum rpm (same MA 16x8 clasic) 7710 rpm. So it gained about 300 rpm (with glow plug powered). I removed the power from the glow plug and rpm dropped to 7300 rpm. However it run smooth. I tried how low I can get. At 2500 rpm it started to run rough and eventualy died.

Next test was idle with glow powered. I was able to get to 1550 rpm, but when I opened the throttle the engine just died. I think I needed to adjust Low end on carb and open it a little for smooth run.

Next test was to start it by hand. Out of three times I was able to start it once. I believe again with right carb setting on Low end it can be started by hand.

CONCLUSION:

1. Better power with methanol-gasoline mixture - Myth CONFIRMED I gained 300 rpm that translates to about 1/3HP more.
2. Can run without glow battery - Myth BUSTED . It will not get reiable idle without on board glow battery.
3. Can be easier started - Myth CONFIRMED. With proper carb setting it should be able to start without electric starter.

However I noticed it takes a little more fuel - I needed to open Hi end about 1/2 turn. So plane may need a little bigger tank.

I didn't make my mind yet, what I am going to do. So far I have 0.5l of Castrol racing oil, i gallon of methanol and a lot of thinking.

RysiuM

There is still one more thing you'll need to do in order to get better idle, and that is you'll need to open the ventury openning to about 0.35 inch diameter the stock carb has to small of a ventury for the fuel demands, that is why it won't stay on while idling; just scrape the ventury hole with an xacto knife until you see that the diameter is a little bigger than the original hole,also gutt out the muffler and that would be your last modifications that you will need in order to have a smoother running, lighter engine, By the way the 25 FL engine likes to swing a 15x8 propeller but if you need a bigger diameter prop try an APC 16x4W prop and believe me you will have performance out of this baby!!!!

That's exactly the thing I don't want to do. It does not explain why it idles very well with glow plug heated. I believe it its not the fuel delivery problem but the glow plug doesn't stay hot below 2500 rpm.

I run it on aluminum muffler from whackerengines. I have already gutted the original muffler - it runs the same as the amuminum one.

I run 8300 rpm on MVVS 1.6 (26cc). 16 inch prop is the lowest I can get. This Poulan 25cc runs MA Clasic (it is like a swinging piece of 2 by 4) - with 15 inch prop I will probably get over 9k rpm.
Actually I bought APC 17x6 for this motor to try. I should get at least 7500 rpm on methanol-gas fuel.

RysiuM

Aug 05 Model Aviation column The Engine Shop by Joe Wagner has good information on Glow Plugs. Rossi, Fireball, OS ( & Enya?) glow plugs come in different heat ranges. Also, plug may not fire, even if glowing. Also, effect of moisture in fuel.

Aug 05 Model Engine News article Engine Maintenence by Dave Gierke: Demon Clean varnish remover is available from Cooperfuels.com.

Try an O.S. F (four stroke) plug thats the one that has worked the best for me it has to stays hotter for longer time at idle than normal plug because of the non-ignition cycle at exhaust

But how do you explain 300rpm drop when I disconnected the battery? This is full throttle. I guess I need hotter plug for this engine. I wonder if I want to play with glow plugs again. The reason I started to play with gas engines is to get rid of all kind of problems with glow plugs - to old, to hot, to cold, and so on. When glow plug is powered all the time I know it will fire the same as long as the coil is not broken.

I think I like the gas-methanol mixture tho. It is additional almost free power. Methanol for 2.99 a gallon is almost the same as gas, but when mixed 50-50 the fuel consumption is just a bit higher, but not 2:1 like with methanol only. The other benefit is possibility to start engine by hand. Then I will not need to carry heavy battery to the field. Just like my other gassers

I have the next engine ready (see the thread [link=http://www.rcuniverse.com/forum/m_3192059/tm.htm]Step by step converting Poulan 25cc FL trimmer[/link] ) and this one will be my glow-gas engine. The first one stays on magneto for my Wilga. Light glow-gas may find a way to Funtana 90.




RysiuM

I think you should use 2% oil (40-50:1 ratio), it helps with a cleaner burning and better idle

Ok, guys I was skeptical. But I just tried gasoline on glow and my Robin 24.5cc conversion engine runs great. I am using just plan regular (87 octane) and 50:1 Amsoil. The same as I was running with a C.H. Ignition. I was getting 7200 RPM on ignition on a Zinger 16/8 prop and got 7500 on the glow. I used an OS #F plug that I had laying around the shop. It started very easily by hand and idle and transition were great. I plan to run this setup on continuous glow for a few flights on my test airplane and will provide more feedback.

Do you power the glow plug all the time, or just for starting and then engine continues to run with battery disconnected?

RysiuM

"Do you power the glow plug all the time, or just for starting and then engine continues to run with battery disconnected? "

you still haven't absorbed the method by which a glow plug works in a glow-engine! .... there is a catalytic reaction between the methanol and the platinum in the element which keeps it hot..... no methanol, no catalytic reaction.... gas only or very low methanol content will require a battery to keep the plug lit....

[:-]

With gasoline you must power the glow plug 100% of the time. This is really no problem. Not much weight gain with a couple of 1800mah nicads wired in series. Still lighter than the mag or electronic ignition. I want to run this system for awhile to see how reliable the full time glow is. If the glow plug dies in flight, things might get interesting. One of the reasons we go to gas is for more reliablity.

When you say "a couple of 1800mah nicads wired in series", are you using 2.4V nominal for glow plug heat?

Bruce

Whoops. I meant parallel. Powering the plug with the nominal 1.2 volts. Just got through running a full tank of gas through the engine and I am still getting the same performance. I plan to fly the engine in the morning and will provide the results after I get home. I am still wondering what the down side is on this setup. It has to be the life of the plug. I will run the one I installed to failure to see how long it will last. Oh and one more thing, it likes to start backwards just like some of the 4 strokers and if you try to start it at anything above high idle it will bit you (ouch). I hand start it so an electric starter would solve that problem.

More tomorrow.

Thanks for the nice explanation. I did know that, but what the heck, I can read it again. My question was to clear things out, as for the last couple days we were trying to test what would it take to not power the glow plug.

Anyway, your test are quite consistent with my on Poulan 25. When I get back home to California (I'm in Jew Jersey on busines again) I will try my second Poulan running gas-methanol mixture for a little longer time just to see what is the milage on mixture compared to pure gas and what is the power gain. I have APC 17x6 that I will run on it.

RysiuM

It may be possible to hook up the 2 nicads in series. I think there is a 2 volt glow plug ...but not sure on that. The glow may be better...as long as the plug does not burn out!!!! Good Luck Capt,n