Duncman

I think I'll throw this out there and see what names I get called!!!! Just read an article in Model Airplane News by Clarence Lee and he recommended white gas, no ethanol and the octane rating will not be an issue with our small bore engines as flame propagation issues associated with large bore engines does not exist. He is an authority on the subject, any thoughts?

dirtybird

My Feedback: (5)

[QUOTE=Duncman;12047563]I think I'll throw this out there and see what names I get called!!!! Just read an article in Model Airplane News by Clarence Lee and he recommended white gas, no ethanol and the octane rating will not be an issue with our small bore engines as flame propagation issues associated with large bore engines does not exist. He is an authority on the subject, any thoughts?
How long ago did he write that?
My ZDZ 80 called for premium gas. I used coleman fuel until they started to ask $10/gal for the stuff. That is real low octane. That engine expert from the Netherlands claimed I would destroy the engine. Maybe I did. I sold it.

Duncman

dirtybird, that is one way to solve it, that's why I stick with new. Mr. Lee's article appeared in the July 2015 issue of Model Airplane News. $10.00 a gallon is better than $20-$30 for glow fuel but way worse than $3.29 gal. for pump gas. He claims the octane is not important in small bore engines. I've heard that elsewhere from our local folks and also have read it in other publications from other authors. Just interested in opinions.

ahicks

My Feedback: (2)

What is the objective/purpose of running white gas in preference to pump fuel? Overcoming the smell of pump gas maybe, or is there another reason?

pilotpete2

I just stopped at our local airport and just payed less than 5 bucks for a gallon of 100LL.
Pete

BarracudaHockey

My Feedback: (11)

A Fiji bottle with viton clunk line and a ceramic clunk (Wrong way builds these so you can just drop them in) are as bullet proof a fuel tank installation as you can get.

Propworn

My Feedback: (3)

I'm setting up a G38 for white gas now for a customer he lives in an apartment and does not want the smell of gas in his car or his apartment. Cost is not an issue. Only reason I can see for going this way.

Dennis

Duncman

I think the point Mr. Lee is trying to make with white gas is that you don't need the additional octane to get satisfactory performance and it doesn't have the 10% methanol that is becoming more and more prevalent. One of our pylon racers decided he would compete with gas rather than glow and standard pump gas didn't perform well for him so he tried 100 LL avgas, didn't give him any significant improvement in lap times so he switched all back to glow and now he is competitive. That experience got my evil mind to thinking "why not use glow fuel in a gasser"? That may not be that stupid an idea, same formula minus the oil mixture that dragsters uses, the main difference is our engines are not supercharge. I guess this early morning coffee has me thinking more than I should, I'll be quiet.

Truckracer

My Feedback: (19)

Duncman, you're making way more work out of going to a gas engine than is necessary! Most of your concerns are not founded in any facts I can think of.

Buy a quality engine of your choice, install the engine in a decent airframe, use a prop in the size range recommended for the engine, use accepted and normal fuel system components, use quality fuel and oil, start the engine, adjust the needles then go fly.

MTK

I've used avgas for 6 years now. I've learned a thing or two along the way....
Avgas is low lead, not unleaded. Spark plug will need cleaning every 10 gallons or so....about 120 flights of 15 minutes each for a 30cc class engine.
The correct mixture for the application will result in no significant gunk build up in the head and piston. Squeeky clean inside after 40 hours of operation
Avgas does NOT result in more engine power. Higher Octane number does not mean more power without engine modifications.
Premium autogas produces slightly more power than Avgas. (will turn the same prop at a couple 100 R's higher at full throttle)
Storage and shelf life is measured in years. I'm burning off the last of the 5 gal jug I filled two summers ago. There have been zero changes required.
No significant smell; whatever little there is, is actually pleasant
Current pricing puts Avgas at about 4$ at my local muny airport. Cheap, cheap but not as cheap as auto gas. To me that's the least of the concerns with gasoline
And last but not least, Avgas works great in our small mills. But do watch out for plug build up. The engine will run erratically (if at all) if the plug has bridged its element

Let me suggest you tell your friend to use an appropriate tuned system if he wants to race his gassie. A tuned pipe really extracts considerably more output from any of our small mills.

Glow fuel has both methanol and nitro methane, both of which add oxygen to the mix. Of course, glow fuel is burned at a rate of about 2 to 1 or more compared to gas which has advantages over gas. Nothing makes horsepower like timed ignition and "glow fuel", displacement for displacement. Dragsters are the epitomy of max output for a given displacement (mostly if not pure nitro methane).

vertical grimmace

My Feedback: (1)

Ok, so now that we have all of these other topics solved, and we are getting along with each other quite pleasantly now, how about we talk about OIL! lol JK, (we really should not)

lamarkeiko

My Feedback: (1)

Another question I have is on engine mounting, and the clearance between the firewall and the carb. I just received my new Hanger 9, 2 pc aluminum engine mounts. They have slotted rails, and with the engine mounted as far forward as possible, I will have a clearance of 15/32" to the firewall. The choke, when open is about 3/16". Is that ok? Should the firewall have a hole, say about 1' in dia. for more air to the carb? I hope this doesn't sound like too dumb of question.

Lamar

vertical grimmace

My Feedback: (1)

Yah, just get a Forstner bit, and punch a ho;e out in the firewall. Better yet, get a velocity stack that will go through. Then your carb will get static air from inside the plane. Beneficial in eliminating the chaotic swirling air from inside the cowl.

ahicks

My Feedback: (2)

Or just leave it as is. It'll run fine that way.

If you need convincing, open the throttle to just beyond half open. That's about where it will be when the engine is at full rpm. Now look at the throttle plate and take a stab at how much air you could possibly stuff through that opening.

Or, if it'll make you sleep better, go ahead with your plan for the hole.

That should open another discussion. ;^)

mustangman177

X2

Just bought one of these from WWRC and solved my engine surging prob. Was using a Hayes fuel tank.

Duncman

Truckracer, was just commenting on an article that Clarence Lee wrote on the subject and looking for some thought, you gave it. The only comment of fact was an observation made by several of us with a radar gun, certainly not scientific but still an observation, no intention otherwise. The other was simply a thought, nothing more.

av8tor1977

My Feedback: (6)

With all due respect to Clarence Lee, do not run Coleman Camp Fuel. It has an octane rating of around 50. Some engines can get by with it, others will burn up. I use it for a storage fuel, and just running my high performance engines briefly on it I can notice a definite increase in heat generated. It's just not worth taking the chance....

And just using it as a storage fuel, I have noticed that once mixed with oil it has a limited shelf life.

AV8TOR

dirtybird

My Feedback: (5)

Have uou verified that temperature increase in the air?
I ran a G45 for many years with no problems on coleman fuel.

lamarkeiko

Gizmo-RCU

My Feedback: (27)

I run Non-ethanol preminum which is available here in Idaho. One benifit is that If I have a small ammount left mixed in the can but not enough for the days flying I put it into one of my saws and mix a new batch. This the only gas I use in my two strokes especially larger chainsaws
and some saw Mfgs. call for this. I use synthetic oil at reccommended rates and all is well. I don't see any benifit from using white gas myself, extra costs is about all. Non-ethanol stores much better when the engine is left wet which I do on all of my 2 strokes.

My system works well for me and is no great mystery....My plugs don't seem to build up carbon and at about $3.00 ea. at the auto parts store (NGK CM 6) big deal! My carb and fuel soft parts don't "melt" down like I have had on older saws with ethanol!

In my view heat is your enemy, lean carb settings, over propping and lack of lubrication are will do more than anything to distroy these little engines.

acerc

Many things we do in our hobby is up for interpretation and opinion. Most that give advise don't actually know or are advising from a slighted perspective. Most manuals are written to give the best opportunity to an unknowing purchaser. Todays electronics do not have the issues of yesteryear, most oils are so far above yesteryear on abilities there is no comparison. So anyone starting out and asking questions are pretty much on their own because as with this thread the advice is so varied and so argumentative they would be better off learning the hard way without asking anything.
I am not going to say I know anything or don't know anything but rather this, here is(in video below) a brand new Valach 170. It is being broke in on a stand (supposedly a bad thing), it is being run with 25-1 mixture (only because of the bottom end/crankcase) third run and to date is at 40-1, all the electrical components are within 4 inches of each other (supposedly a bad thing), many things we do in our hobby is up for interpretation and opinion. I must be really stupid doing these things to a $2500.00 motor, right????
Cheers!!!


https://www.youtube.com/watch?v=wC_OvWXK5hs

https://www.youtube.com/watch?v=KiU0-nEW_jc

vertical grimmace

My Feedback: (1)

I look at it like this, essentially these engines are the same as what is in your chainsaw or weedeater. So I have no problem using cheap, low octane pump gas. The only thing that does not like it is the stopper tank. So I eliminated that, and I have never had a problem otherwise.

ahicks

My Feedback: (2)

I really wish I could believe this:

" Most manuals are written to give the best opportunity to an unknowing purchaser."

but my experience would lead me to believe it is slanted way more towards minimizing warranty dollars.....

MTK

Oh c'mon VG. An oil argument is good for the hair.
I prefer olive oil meself....from Crete....cold pressed, extra virgin. It has to be waylayed, parlayed and marmalade. But don't ask about its mixture. LOL

acerc

Not necessarily true, chainsaws and weed eaters have a heavier case, larger fins, and also funneling of the external air by way of a fan on the flywheel.

Both kinda have the same end result, if the purchaser follows the instructions.

That's funny right there!!

acerc

All I'm really trying to say is it must be really tough for a newbie when they ask a question get so many different and widely ranging answers.