Van's Air Force
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Ethanol free gas
- Thread starter VETE76
- Start date
AK4x4
Well Known Member
It works
Lycoming IO-360-B, E, L, & M series engines are approved for operation on unleaded fuel. The fuel needs to be 93 AKI conforming to ASTM D4814-09b, see Lycoming SI 1070S table 3 for specific details & other approved models.
Lots of info in the forums of folks successfully running unleaded fuels and its positive side effects. (no lead sludge, no lead on plugs or valves etc.) Use caution when designing the fuel system as auto fuel can increase the risk of vapor lock, especially with winter blend fuel moving into warmer weather. Also unleaded fuel doesn't store long term very well, so use it up! Good luck, Russ
Lycoming IO-360-B, E, L, & M series engines are approved for operation on unleaded fuel. The fuel needs to be 93 AKI conforming to ASTM D4814-09b, see Lycoming SI 1070S table 3 for specific details & other approved models.
Lots of info in the forums of folks successfully running unleaded fuels and its positive side effects. (no lead sludge, no lead on plugs or valves etc.) Use caution when designing the fuel system as auto fuel can increase the risk of vapor lock, especially with winter blend fuel moving into warmer weather. Also unleaded fuel doesn't store long term very well, so use it up! Good luck, Russ
Paul K
Well Known Member
I don't have long term data but I have been burning 91 to 93 "boat gas" in my IO 360 for the last 100 hours. I ran it in one tank and 100LL in the other tank during the test. Switching back and fourth between types, under all conditions, I couldn't detect any changes while recording all engine data and having it reviewed by an engine guru. I would have thought there would have been some measure that was different but no.
I even ran the engine in the dangerous "red box" area of operation and there was no difference. The lower octane didn't cause any temp spikes or detonation indicators.
The only detectable difference I could find is harder hot starts, mostly on hot days. Other than that, absolutely no difference other than about $2/gal. If I burn 8 gal/hr, that saves me $16/hr. If I run it for 1000 hrs, I save enough to rebuild the engine if needed.
Please don't take any of this as advice or gospel. It is just the way I choose to go. Do your research and make your own choices.
Data:
ECI IO 360 built from kit
8.5:1 pistons
Dual P mags
Silver Hawk Fuel injection
Cold air induction
Normal run 50LOP, WOT, 2350 RPM
Final note, not that it matters but there are planes at our airport that have never tasted lead and they are running fine, one has about 1700 hrs with no issues ever. Owner plans to run it as long as possible and only rebuild on condition, as needed, not per TBO. There are also a couple of Very expensive complex birds on the fields that have been run by the book and have both just had top ends rebuilt. Go figure!
I even ran the engine in the dangerous "red box" area of operation and there was no difference. The lower octane didn't cause any temp spikes or detonation indicators.
The only detectable difference I could find is harder hot starts, mostly on hot days. Other than that, absolutely no difference other than about $2/gal. If I burn 8 gal/hr, that saves me $16/hr. If I run it for 1000 hrs, I save enough to rebuild the engine if needed.
Please don't take any of this as advice or gospel. It is just the way I choose to go. Do your research and make your own choices.
Data:
ECI IO 360 built from kit
8.5:1 pistons
Dual P mags
Silver Hawk Fuel injection
Cold air induction
Normal run 50LOP, WOT, 2350 RPM
Final note, not that it matters but there are planes at our airport that have never tasted lead and they are running fine, one has about 1700 hrs with no issues ever. Owner plans to run it as long as possible and only rebuild on condition, as needed, not per TBO. There are also a couple of Very expensive complex birds on the fields that have been run by the book and have both just had top ends rebuilt. Go figure!
BruceEicher
Well Known Member
Price vs hassle
At two dollars difference "boat" gas sounds appealing. Though I find as much as a $1.50 price difference from one filling station to another destroying most of the savings. (you can pay AV fuel prices at some dockside resorts).
I am going to take a drive by a few stations and check my local prices.
Here's a website to locate such stations.
http://pure-gas.org/?stateprov=OR
One local airport is working on "pure gas" that I know of. But I bet it will be over $5...
Are others getting the fuel at their airport?
Or how are you moving it? Cost of such?
Plus my hangar condo association has rules against storing large fuel containers...
The more I think about it, and write this, the less is saved...YMMV
At two dollars difference "boat" gas sounds appealing. Though I find as much as a $1.50 price difference from one filling station to another destroying most of the savings. (you can pay AV fuel prices at some dockside resorts).
I am going to take a drive by a few stations and check my local prices.
Here's a website to locate such stations.
http://pure-gas.org/?stateprov=OR
One local airport is working on "pure gas" that I know of. But I bet it will be over $5...
Are others getting the fuel at their airport?
Or how are you moving it? Cost of such?
Plus my hangar condo association has rules against storing large fuel containers...
The more I think about it, and write this, the less is saved...YMMV
Sam Buchanan
been here awhile
My O-320 160hp is very happy on non-ethanol 93 pump gas. Been flying 100% auto gas for over a year and haven't found any service issues. The engine runs cleaner and the belly of the plane doesn't have lead deposits on it anymore. All gas is filtered through a Mr. Funnel as it goes into the wing tanks.
I was pleasantly surprised to find $3.35 auto gas last week at our local source. That is a huge savings over the 100LL on the airport.
rv7charlie
Well Known Member
160 hp O-320 fixed pitch on 93 octane e-free mogas for at least 5 years. Plugs never foul; subjectively, engine actually seems to run better. As mentioned earlier, the biggest caution is 'winter' gas in hot weather (fly a lot).
I've occasionally seen 93 octane only 50 cents/gal cheaper than avgas, and I still run it because it keeps the engine cleaner and running better.
It might be worth mentioning that there are people on this list that are running e-gas with no ill effects. The only component in the fuel system that is known to be e-gas vulnerable is the (very) old mechanical fuel pump; the diaphragms slowly deteriorate with ethanol. However, according to the mfgr, all newer mechanical pumps have e-gas safe diaphragms. Some very early versions of fuel tank sealant *might* be vulnerable to auto gas in general. I've had some leaks in my 1992-completed RV-4, but that might just be poor build technique (the tanks had leaks prior to running mogas, too). They were old enough that Van's was still recommending 'slosh' sealant.
The newer sealants' data sheets indicate that they are safe for just about any fuel we're likely to run in a piston engine.
Charlie
I've occasionally seen 93 octane only 50 cents/gal cheaper than avgas, and I still run it because it keeps the engine cleaner and running better.
It might be worth mentioning that there are people on this list that are running e-gas with no ill effects. The only component in the fuel system that is known to be e-gas vulnerable is the (very) old mechanical fuel pump; the diaphragms slowly deteriorate with ethanol. However, according to the mfgr, all newer mechanical pumps have e-gas safe diaphragms. Some very early versions of fuel tank sealant *might* be vulnerable to auto gas in general. I've had some leaks in my 1992-completed RV-4, but that might just be poor build technique (the tanks had leaks prior to running mogas, too). They were old enough that Van's was still recommending 'slosh' sealant.
The newer sealants' data sheets indicate that they are safe for just about any fuel we're likely to run in a piston engine.
Charlie
Bill Boyd
Well Known Member
Not in Virginia
There is a specific disclaimer that the off road tax refund is not available for aircraft unless owned and operated by the commonwealth.
- because so much of my road use taxes is devoted to aviation infrastructure, I pay this tax gladly. Said no one, ever.
There is a specific disclaimer that the off road tax refund is not available for aircraft unless owned and operated by the commonwealth.
- because so much of my road use taxes is devoted to aviation infrastructure, I pay this tax gladly. Said no one, ever.
