westwind77

I'm going to be running a Zenoah G-26 and was curious what fuel octane I should be burning? I have the option to run anything from 87-93 with 10% ethanol or to run high octane AV fuel with lead. I thought I read the high octanes are not good for these, is that true? This is just for recreation & fun, no racing. Thank you!

blizard05

Many of us , run camp fuel

mistycreekboats

My Feedback: (1)

I run Marine gas (no ethonal) think its around 86 / 88

Always mix bit of your gas / oil in a glass jar first and shake. Some oils & fuels don't get along and will seperate quickly. Do a test and let it sit to make sure it doesn't seperate from fuel.

Zoom Zoom

Randy

westwind77

Is there a particular reason for that? Just to avoid the ethanol?

I did ask around and found a lawn care shop that will sell 'normal' octane fuel with no ethanol, decent bit more expensive, but it is not like it is burning a ton of fuel anyway. I wonder if that is the way to go. Avoid the possible too high octane fuel with lead, and avoid the ethanol normal fuel.

mistycreekboats

My Feedback: (1)

They run camp or Coleman fuel because of no smell like gas.

Randy

MTK

Higher octane up to 100LL aviation gas doesn't hurt these engines. They run fine and don't need much on the needles; maybe a slight tweak. I prefer using avgas because of lack of smell and long shelf life. Buy at any muni airport

There is also pure gas and marine gas which contain no alcohol and many have had success running these gasolines. They are not available everywhere tho. Check online for pure gas for availability in your area

There is racing gas at around 110 octane but I don't believe this stuff will work well in these small gassies. The burn may be too slow to be useful.

Rocketman612

My Feedback: (85)

+1 Avgas

No smell and much better shelf life. All my engines DA,DLE and Zenoah's love it.

Pete

Justaddwata

My Feedback: (3)

Don't fall into the trap of thinking high octane will make your engine perform better - it does not - and certainly of no benefit with a zenoah.
A good read - http://www.nicoclub.com/archives/gas...ane-myths.html

I run camp fuel whenever possible. Camp fuel is very low octane and low odor. Has a long shelf life and burns very clean. You will not be able to read plug color using camp fuel as it does not color the plug - if you need to tune try regular unleaded and get the tune right - then switch to camp fuel if you like - no adjustment needed.

More important than octane - use 8oz of oil/gal. You will get more performance with plenty of oil in marine use. If you try 50:1 your motor will not last!!

geeter

My Feedback: (110)

Why not buy true fuel avail, at lowes or Home Depot.? Already has the oil in it and is ethonal free and 91 octane. It's 40-1 ratio so if you need 32-1 just buy a little bottle of synthetic and mix in 1/4 oz per quart of oil. No gas smell either. It's cost is around 5.00 per quart though. I run it in my 20 cc valley view engine. I use 32- 1 mix but can go to 40-1 after break in . There is no advantage in 40-1 except a little less oil. Better off staying with 32-1 these smaller gas engines need good lube so they run right. Cheating on oil will only cost ya in the long run. Hey just say'n what I use. Good luck....RON

Lifer

My Feedback: (1)

8 ounces of oil to the gallon? Isn't that a 16-to-1 ratio? Sounds like a bit much.

westwind77

Thanks for the responses so far, learning a lot! My manual recommends at 32:1 mixture (4oz to 1G). I see ACE also carries the TruFuel in both the 40:1 and 50:1. I have a feeling I am going to either run the 100LL or the TruFuel as I can pick that up a minute down the road from my house (and add a little extra oil)....which leads me to my next question.....is there a specific brand/type of oil you like to run? I see the TruFuel runs synthetic oil so I would have to match that if I add some.....however if I run the 100LL and add my own oil is there a reason to run the synthetic vs say the TWC-3 marine 2 cycle oil? Thanks!

eaglen2fb

My Feedback: (41)

Pump Gas 87- 89 octane with 10% ethanol i have been using it for years The key is use a good name brand two cycle oil Like Husqvarna or Stihl chainsaw or even Klotz oil. Those oils are design to work under a load in harsh conditions and ran at 50:1 ratio .People tell me all the time that the carburetor diaphragms will dry up that is true but its not because of the ethanol its just with age Walbro and Tillotson recommend to put a carb kit once per season meaning every 12 month which no one that i know of does, I have carbs that are five to ten years old and never touched them and i attribute that to running a good grade 2 Cycle oil.

westwind77

I think I have my final solution and want to run it by the experts here! I am going to run the TruFuel....but want to run the 4-Cycle fuel and ADD my own oil (like the Stihl or Husqvarna as mentioned above). Since the bottles are already 32oz all I have to do is add 1oz of oil, and done. Does anyone know of a reason I should not run the 4-cycle fuel and add my own oil? I like the piece of mind knowing that I added the correct amount. Amazon sells a case of 6 for $35 w/prime shipping.

eaglen2fb

My Feedback: (41)

4 Cycle fuel has Nitro and castor oil the Nitro will eventually corrode the bearings in the engine and the castor oil tends to gum up the engine would not use that At all. 50:1 is 2 1/2 ounces per gallon.

geeter

My Feedback: (110)

I think the last thread was a bit off. Your talking about 4 cycle nitro fuel. We're talking gas engine 4 cycle fuel without the oil content and no ethonal either. Yes I see nothing wrong with 4 cycle gas. And adding your own oil. You can use whatever you want then. All true fuel has synthetic oil already in it at 40-1 or 50-1. But that is another way to go. I like stihl ultra oil......RON

geeter

My Feedback: (110)

Yeah lifer that 16-1 gas oil mix is way to rich. Whoever uses that could have a smoke plane ..... Without a smoke system on board LOL. And a very carboned up plug and cylinder.

pkoury

My Feedback: (7)

87 octane with ethanol pump gas and Stihl ultra oil 50:1, one 2.6oz bottle per gallon of gas. I get a gallon of fuel for about 6 bucks.

jharkin

My Feedback: (2)

Its a G26. They are built like tanks and will run on just about anything. Simple answer is read the manual, run regular with somewhere between 32:1 and 50:1 of any good quality two stroke oil.

There is very little difference in energy content between fuels. Higher octane blends burn slower and this helps prevent detonation in high compression engines with aggressive timing. The Zenoah is timed for regular so as mentioned above anything higher (premium, race gas or avgas) will actually reduce power slightly.

Its also been proven they run just fine on Coleman camper fuel (a.k.a white gas) which is 55 octane naphtha. Showing that the octane rating really is not critical at all. the benefit as mentioned is it doesn't smell. the downside is its $10+ a gallon so you might as well be paying for nitro. I say dont bother unless you keep your plane in the living room.

Some guys run a100LL AVGAS claiming its cleaner and last longer. It does last longer, but that has nothing to do with ethanol, it is because it has less additives and is refined better for a more consistent vapor pressure (important so your Cessna doesn't experience vapor lock at 12,000ft). You aren't flying a 360 cubic inch 4 stroke lycoming powered Cessna at 12,000ft... you running a 1.6ci two stroke in a boat - so again not worth it unless you have a need to keep your gas 2+ years before you burn it. Downsides - its expensive and you will be breathing lead fumes.

Some guys will tell you to avoid ethanol. Al the scare is blown way out of proportion. It does not cause gumming (its acutally causes less gumming than old gas since the ethanol is a strong solvent/detergent) and the rubber parts in modern engines have been tethanol safe for years.

Some guys will even tell you ehtanol causes water problems... But what do we do to solve water problems? We add dyrygas. Go read the label and see what the active ingredient is in drygas

The premixed gas in a can is like bottled water. Stick something in a can with a flashy label and people magically forget they can get it elsewhere for free/cheap.

I run 87 octane E10 pump gas mixed 32:1 with Penzoil air cooled two stroke mix (conventional). This is the most popular fuel mix in the ultralight community - these guys trust their life on it and its cheap, runs me about $3 a gallon oil included right now. Ive been running this mix over 10 years on my DA, both my heli Zenoahs (that run 12-13k rpm sustained), my chainsaw, and my weedeaster. Havent killed an engine yet.



So once again, save your money, run straight regular from the pump with 32:1 and be happy about all the cash you saved.

Lifer

My Feedback: (1)

Someone made a reference to marine 2-stroke oil. I believe that is the wrong oil to use as our engines are air cooled, not water cooled.

Can someone else pipe in on this, please!

stegl

Pump gas hasn't had lead in it for many many years with the exception maybe of aviation fuel. Lead is still used in av gas because without it , it would raise hell with the valves, valve guides and valve seats. The cost to revalue and reseat aircraft engines would be horrendous . AND then the engines would require recertification because of the changes.
Some of the higher octane pump gas may not have methanol in it and will be martked on the pump.
Most two stroke marine oil is TCW3 ( or similar) rated as it doesn't leave oil float on the surface of waterways. I believe it desolves in the water....... Pretty much all new marine engines now are 4 stroke because of that.
About the main thing leaded aviation gas will do is leave more deposits on the spark plugs. If Coleman white gas works , use it.

For oil mix , 2 stroke synthetic that is JASO FC or better FD rated are excellent. Some kerosene and jetA burning turbines use it as it can run ar very high temps before burning or carbon in up.

big issue with methanol in gas is that some of the rubber gaskets in carb/pump systems are not combatable with the gasket material as it causes them to swell. This may be on older engines. I would think that the newer ones have the newer methanol combatable material for gaskets and seals.

ok enough , the information is here ... Take your pick....lol

MTK

The recommended 32:1 works just fine. Use only good quality 2 stroke oil. Many use Pennzoil, Stihl Ultra synthetic, Redline synthetic and there are a couple other great oils, at anything from 30:1 to 50:1. I've used Bel Ray MC1 motorcycle racing synthetic from the start 6 years ago, at 50:1, and have had outstanding performance. I use the same mix for break in and after. Any of these oils work well in toy airplane land.

One thing to know regarding avgas, top end rpm will be slightly reduced (200-300 rpm) compared to premium auto gas. It makes no practical difference in my application (Pattern aerobatics) since I never use full throttle anywhere. But this might make a difference to you. Nevertheless, the great number of positives outweigh this small negative by a wide margin....FWIW 2U

Ron Olson

My Feedback: (1)

I've been running Coleman fuel for a few years now with 8 oz. of Honda HP-2 in them. Seeing how Honda is not selling it anymore I'm going to switch to Lucas which I found at O'Reilly's which for me is across the street from Wal-mart where I get the Coleman fuel at. I recently tore down a 6 year-old engine at it looks like the day that I got it.
Ethanol will ruin the diaphragm in the carb, one of the many reasons why I switched away from gasoline.

mysteryrc

1 gallon Coleman fuel + 8oz quicksilver

geeter

My Feedback: (110)

yeah lifer, twc oil shouldn't be used in air cooled engines save it for your jet ski or outboard.there are plenty of air cooled oils out there to choose from. either synthetic or the regular stuff.

westwind77

Thanks everyone! I just ordered a case of the 4-Cycle TruFuel and will swing by my local landscaping shop to pick up some good oil.

Should I run a richer oil mixture during break it, manual makes no mention to do so, just reduced throttle as with most break in periods?

Ethanol has been a nightmare for marine industry (which I have been in for decades). Anything newer is 'ok' but anything pre-ethanol or with carbs has issues. I have seen everything from complete fuel line failures where it 'melts' from the inside and clogs carbs/injectors as it was not ethanol resistant to large below deck poly tanks breaking down and clogging injectors after x amount of hours run time. Obviously anything produced today is designed to deal with e10 without a problem, but most people are not in that boat, pun intended.

Thank you to everyone for your insights!