Can the IO540 run mogas?

[propsync]

I happen to run into this article today which leads me to believe pipistrel is attempting to gain lycoming certification to run certain engines on mogas.

http://www.flyingmag.com/aircraft/pi...MjYxNTg5MTU4S0

[pierre smith]

Yes, if it's 8.5:1 compression....same cylinders and pistons as a O-360.

We used to taxi our Pawnees up to a gas station in the '70's, working off roads and buy mogas. They had the 230 horse, derated
O-540's.

Best,

[propsync]

Noted, thanks!

[ppilotmike]

In order to do this, wouldn't you have to protect your fuel tank interiors somehow? I thought the mogas causes corrosion in the tank and lines, no?

[N941WR]

Originally Posted by ppilotmike

In order to do this, wouldn't you have to protect your fuel tank interiors somehow? I thought the mogas causes corrosion in the tank and lines, no?

If the FAA approves MOGAS for aviation, it will not be the same stuff you get from the pump at your local gas station. It will more than likely be ethanol free and won?t have the other additives you get in your pump gas. Thus you will have no problems with corrosion. If corrosion is a real fear or not, I don?t know.

[Vlad]

Originally Posted by ppilotmike

I thought the mogas causes corrosion in the tank and lines, no?

No if you burn it fast and do not let it sit in the tanks

[paul330]

Is the question WILL a 8.5:1 IO540 run on Mogas or is it APPROVED to run Mogas?

As I understand it, the IO540 is not approved even though it has the same compression as many 360s that ARE approved. See Lycoming SI1070. In Europe we now have unleaded Avgas (UL91 or 91/96UL) which is approved for many 540 models.

The issues with Mogas are well documented but in summary:

- it is cut with higher vapor pressure for auto use which can lead to vapor lock. The VP is not consistent and changes with the seasons.
- it us getting near impossible to obtain Mogas without significant percentages of ethanol. As you mention, ethanol can attack various components unless you make some mods. Also, there is an issue where any water in the tank tends to bond with the ethanol in preference to the gas and drop it out of solution. You therefore lose your anti-knock agent (short version!)
- The stuff you get at the gas pumps is not subject to the same quality controls as Avgas.

Having said that, I believe your experimental rules allow you to use it and I know there will be endless posts saying how wonderful it is...... And, yes, there are various ways to mitigate many of the issues. What you need is a US equivalent of our UL91 - but it's an environmental bonus and only a very small financial one.

[9GT]

Did a 2.4 hour Phase 1 testing flight last week in my IO-540 V4A5 RV-10. Left tank 100 LL, right tank pure 90 octane ethanol free "Recreation Fuel" a local gas station started selling recently. Took off and landed on the 100 LL and put 1.8 hours on the right tank at altitude's up to 9500' msl. The engine ran great and virtually no noticeable differences showing on the engine page. The Lycoming tech guys at the Lycoming presented engine dis-assembly/re-assembly seminar at Airventure I attended a few years ago stated the engine would be very happy running mogas. Next time up I'll do some more testing but liking that the rec fuel is more than a $2 per gallon savings.

[propsync]

Originally Posted by 9GT

Did a 2.4 hour Phase 1 testing flight last week in my IO-540 V4A5 RV-10. Left tank 100 LL, right tank pure 90 octane ethanol free "Recreation Fuel" a local gas station started selling recently. Took off and landed on the 100 LL and put 1.8 hours on the right tank at altitude's up to 9500' msl. The engine ran great and virtually no noticeable differences showing on the engine page. The Lycoming tech guys at the Lycoming presented engine dis-assembly/re-assembly seminar at Airventure I attended a few years ago stated the engine would be very happy running mogas. Next time up I'll do some more testing but liking that the rec fuel is more than a $2 per gallon savings.

According to the article, it appears as pipistrel is looking for lycoming to certify the gas for use so that would be a leap.

[smokyray]

Originally Posted by propsync

I happen to run into this article today which leads me to believe pipistrel is attempting to gain lycoming certification to run certain engines on mogas.

Tom,
I ran Non-Ethanol 91 Octane in my Harmon Rocket's 10.4:1 IO-540 C4B5 for 5 years. I currently run it in my 8.5:1 RVX. It's available all over FL and other parts of the USA. http://pure-gas.org/ Works great and is $.4.20 a gallon here. Ethanol's big issue is retaining water within the fuel, hence using Non-Ethanol.
In 25 years of MoGas RV flying, I have found it to run as well or better than 100LL with less plug fouling on the Mag side. My Electronic Ignition plugs never foul, regardless of fuel. There are lots of tips and pointers out there, I just use three.

1. Longer summer run-up (vapor lock prevention in summer)
2. Additives, Marvel Mystery oil, CD3. Optional, but work well.
3. Don't let it sit in the tanks for long periods.

It's the way of the future IMHO...
V/R
Smokey