FlyingArcher

FlyingArcher

Well Known Member
Hello,

I'm currently analyzing the opportunity to buy a used Lycoming O-320-E2A engine, and a question just popped: is this engine able to run with 100LL gasoline, or is it limited to its specs that indicate 80 octane gas?
If limited, is there any conversion process/parts to be able to burn 100LL?

The reason I'm asking is because this engine has been removed from its initial airframe in 1976 and safely stored since then.

Now, I've just read this article on Lycoming web site:
http://www.lycoming.textron.com/mai...keyReprints/general/lowCompressionEngine.html
but I'd like to have other builders comments if possible.

Thank you, and Merry Christmas to all of you
 
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Dan:

I am running an 0320-E2D in my 6A. You can run 100LL with no problem, but I recommend that you

1) Use TCP, which is a lead scavenger. I use 1oz/10 gallons of fuel.

2) Lean your mixture while taxiing as well as in cruise, even below 5000'.

Doing these two things will help to eliminate lead fowling, which is the main problem with running 100LL in our engines that were designed for 80.

Hope this helps. Bonne chance!

Joyeux Noel

Regards,
 
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Works fine on 100 LL

Daniel,
I have that same engine in a Cherokee. It runs fine on Auto gas or 100LL AVgas. Lean before taxiing if you use 100LL.
 
2nd on leaning. Lean aggressively.

Get a copy of the data certificate for the engine. Has lots of good info.

If you run on other than 100ll, make sure you don't have any issues with elastomers in the fuel system with respect to reformulated gasoline.

Got a -E2A on my -8 and it does just fine for me using 160-hp pistons and 100ll.
 
I have the O320E2D in my 68 Cardinal, When I started flying it 15 years ago I was always fouling a plug or two. I was told to lean aggressively on the ground , and go with the REM37BY plugs. Since changing to the above I have flown for years with out a fouled plug. Just overhauled the engine with 2400 hours tt on it last year. Tore the engine down and found it to be in great condition. Had a major done and went with highcompression pistons. Runs great.
 
Thank you

I'm always amazed by the quality and accuracy of the answers on this forum. There are so many knowledgeable people willing to share their experience, I hope I'll be able to give back something once I'm more experienced as a pilot and as a builder.
In my case, I can tell that VAN's owes one to this forum, because a big part of my decision to go with an RV-9A instead of another kit was motivated by the assurance that I would always find help and support here. I'm part of a builders team at my aeroclub, where we are currently building a Jabiru J-400 4-place composite kit, and I can tell you first hand that it's very difficult to find valuable information either from the manufacturer or from other builders.

Thanks again to you, and to Doug Reeves for keeping this site alive.

Oh, by the way, I think I've found my perfect Christmas gift with this engine I was looking at :)
 
Caveman said:
Daniel,
I have that same engine in a Cherokee. It runs fine on Auto gas or 100LL AVgas. Lean before taxiing if you use 100LL.
Click to expand...
Hi Joe,

You mention running on Auto gas. Could you please expand a bit more on this topic, like information on which grade you use, how often, precautions, etc...
Here in France, autogas is about 40% cheaper than 100LL, so you caught my attention here. If I hadn't found this very nicely maintained O-320, I was seriously considering a Jabiru 3300 mostly because of operating costs.

Regards
 
FlyingArcher said:
Hi Joe,

You mention running on Auto gas. Could you please expand a bit more on this topic, like information on which grade you use, how often, precautions, etc...
Here in France, autogas is about 40% cheaper than 100LL, so you caught my attention here. If I hadn't found this very nicely maintained O-320, I was seriously considering a Jabiru 3300 mostly because of operating costs.

Regards
Click to expand...
Although not flying my 80 octane engine yet, my experience with auto fuel is that you can run regular unleaded, as long as it meets the minimum octane rating of the STC under which you operate. (No STC is required for a homebuilt in the US.) For the J-3, Stearman, T-6, UPF-7 and Travel Air 4000 we used to fly at Bi-Plane Adventure Tours we used Exxon regular unleaded aka 87 octane. At overhaul time the engines came up clean, very clean.

Just remember to avoid auto fuel with alcohol additives.

Note, you can always go up in octane but not down. (Even in your car, regardless of what Click and Clack might say. It all has to do with compression ratios. High compression = High octane, Low compression = Low octane.)
 
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Use with Caution

Hello FlyingArcher,

I'm not sure of the legalities of using Autogas in France. Here is the States there is an STC available for certain aircraft / engine combinations. This is a very controversial subject and many people including Lycoming recommend against using auto fuel. Do your research before listening to me or anyone else on the subject. I am but one data point.

For what it is worth I once experienced vapor lock in a 172 using autogas. :eek:

That being said I flew the Cherokee over 700 hours with no issues at all relating to auto fuel. On some cross country flights I used 100LL when autofuel wasn't available.

http://www.autofuelstc.com/

Is a good place to start your research. The EAA also has lots of info. Do a Google search as well.
 
Joe, Bill,

Thank you for your answers.

About legality of using mogas here, a homebuilt is not concerned as it gets a special airworthiness certificate called CNRA (which by the way inspired your Experimental status half a century ago) where the builder is in charge of defining almost everything, as long as Civil Aviation authorities give an approval.
Things would be different for certified airplanes, of course, unless they get STC'd.

Now, my concern is more about the restriction to use gasoline containing alcohol. The fact is that oil companies MUST by the law include an always higher percentage of ethanol in the fuel delivered at the pump in France, so there is no way to avoid ethanol other than using 100LL :(

Anyway, I'm just at the beginning of this wonderful adventure of building an RV, and I have plenty of time to think about this before burning the first drop of gasoline, whatever it be.

Cheers, and Happy Holidays
 
FYI: Octane ratings are different in Europe and the US. I can't remember the formula for conversion. Additionally, you'd have to check for additives in the fuel to make sure it is safe to be ran in your system.

Bonne Annee!
 
FlyingArcher said:
Now, my concern is more about the restriction to use gasoline containing alcohol. The fact is that oil companies MUST by the law include an always higher percentage of ethanol in the fuel delivered at the pump in France, so there is no way to avoid ethanol other than using 100LL :(
Click to expand...
Bummer!

Ethanol, in any quantity is a knock out. It absorbs water, which can freeze at altitude, which can cause you all sorts of problems.

In addition, it can deteriorate the rubber seals in the fuel system (carburetor).

I would stick with 100LL until you can find a source of "clean" auto fuel.

Best of luck with the build
 
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