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MOGAS vs. 100LL and Availability

I know this conversation has been had before, but it looks like its been 10+ years since a thread was updated. I am in the process of purchasing a recently completed RV-12is. Concerned about 100LL usage (increased oil change intervals, wear on the engine/gearbox, etc.) Certainly would prefer to use MOGAS but the availability might not make that possible on a consistent basis. Since the airframe has been flying for a decade now would be nice to get the thoughts of you folks who have been operating them.

Thanks!
 
In the Mogas camp here.

Previous owner did 170 hours on Mogas in SC since 2012.

I've talked to a couple of performance guys that make big bore kit's and cams for Rotax 912ULS and 912 UL's, and to a "T", all of them have said that even with running Decalin, the lead gets under the ring seats, and in the clutch in the gearbox for the prop gets clogged up also with lead. 600 Hours vs 1000 hours for the gear box.

It can be run... but it would be my last choice, Rotax has stated that the 912 is designed from scratch to run on Mogas, not Leaded fuel.

I prefer running full synthetic Mobil 1 4T Racing motorcycle oil 10w-40. It's not really compatible with 100LL, and I prefer the extended oil and filter changes with the Full Synthetic motor oil. So I do what I need to to keep the tank filled up with unleaded Mogas. YMMV, this is what works for me.
 
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Yes, MOGAS is not widely available at airports so you will probably have to use 100LL on cross country trips. At home though, most people pick up 91 or higher octane fuel at a high volume gas station and refuel the plane themselves. There is a right way and a wrong way to do this though so do some research on it here. :)
 
There’s no economic incentive for the fuel industry to ditch lead since it’s such a minuscule portion of their operation. The efforts from Swift and Shell to create an alternative are stalled. It may take a nudge from the EPA, which could come soon if the blue team wins in November.
 
Jon, can you direct me to the location of this info. New to the Rotax. The RV-12is I will be purchasing was recently finished. Will be nice to start it off on the best path for success which sounds like MOGAS at this point.
 
Off topic question, sorry:

But why... if the nozzle of the pump is metal, and the tank you're filling is metal, and you're presumably making contact between the nozzle and the tank... would you need to have the tank on the ground?

Never understood this even when fueling planes either. Seems to me like a separate ground wire is redundant if you're making contact between the pump (which will itself be grounded) and the airframe. Is it maybe to prevent a spark on first contact? That's the only thing I can think of.
 
Off topic question, sorry:

But why... if the nozzle of the pump is metal, and the tank you're filling is metal, and you're presumably making contact between the nozzle and the tank... would you need to have the tank on the ground?

Never understood this even when fueling planes either. Seems to me like a separate ground wire is redundant if you're making contact between the pump (which will itself be grounded) and the airframe. Is it maybe to prevent a spark on first contact? That's the only thing I can think of.

IF your hose has a bond wire in it, and, IF you keep the fill nozzle in constant contact with the tank neck. you may be ok. What happens when high volumes of fuel flow through a rubber hose is static electricity is created, it has to discharge and jumping to the plane at the filler neck can ignite the vapor that is in that area. In reality the fuel transfer rate we have is so slow the chance of building enough charge is slim. BUT it never hurts to error on the safe side.
 
Any issues with type of cans? (i.e. red plastic vs. metal) Also, any concerns about contaminates being introduced in the process of transferring MOGAS from the station to the container and eventually airplane?
 
In my plane (not an RV) on a long cross country where MOGAS availability is an issue, I may carry a couple of small EMPTY fuel cans and use the crew car to get 91 octane. I use 2 1/2 gallon cans because they fit easily. While this isn't for everyone, it works for me. It gets me an additional hour and that makes quite a difference. Plus one can make multiple trips to the gas station. Probably worth pre-planning with the airport on the crew car if you are going to count on this.
 
1000 hours and 8 years of flying Car gas 80% of the time. I found a little water in one preflight sample and have never found anything significant on my gascolator screen at annual. For those of us who flew for years on AVGAS car gas is viewed with a skeptical eye at first, but if you think about it how many times has your car died due to fuel contamination? I have confidence it’s car gas in my 12.

In contrast in 35 years flying my Cherokee I have had AVGAS contamination twice.
 
MOGAS vs. 100LL

I use mogas in my RV-12 whenever I fuel at my home airport. I have 4 5 gallon cans, and I put 4 gallons in them. I am an old man and lifting 4 gallons is easier than lifting 5 gallons. And I have a rule that I always land with 5 gallons or more.

But when I go on a cross country, I almost always have to put in 100LL. So I carry Decalon in the airplane and use it with 100LL. I wish I could use mogas all the time, but it just is not available on most cross countrys.
 
It’s been over 10 tears and 1000 hours since we’ve used 100LL.

When planning cross country use the Mogas websites or AirNav. Call ahead to be certain of mogas availability.

We carry 5 gal fuel bags and filter funnel. They are light and take little space.

If no airport mogas, look for airports near a highway, stop there and use courtesy car. Explain why you want mogas. Give the FBO a nice tip for use of car.

It takes planning, but cross country on mogas certainly can be done.

Jim Butcher
Europa Rotax 914
 
Some folks have put in an Aux 6.5 gallon fuel tank and electric fuel pump to augment their XC range on their RV-12s. It does cut into your gross weight by adding about 60 pounds behind the pilot, so it does affect what else you can carry.

Works fine if you're flying solo cross country with light baggage cinched in on the passenger seat side.

If you keep your fuel consumption rate down by flying 8000-10,000 ASL or above at 5200 rpm or less, 4.5 hours at cruising is very easy to do, with plenty of reserve.
 
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There are some less used airfields next to truck stops that the airport guides don’t list as having mogas. Chiriaco Summit L77 is a good example. I think Grand Canyon Caverns and Amboy, CA are similarly located. I do love the looks I get when I land at L77 and walk over to the gas pump with my 5 gallon can!😝
 
There are some less used airfields next to truck stops that the airport guides don’t list as having mogas. Chiriaco Summit L77 is a good example. I think Grand Canyon Caverns and Amboy, CA are similarly located. I do love the looks I get when I land at L77 and walk over to the gas pump with my 5 gallon can!��

I'd think if there are cars available short term at FBO's, I'd use them to fill up, and explain to the FBO that the motor in my LSA plane is made by a snowmobile and personal water craft engine manufacturer, and it has a gearbox and clutch that gets destroyed by 100LL.

Trying to get a little beta on getting Mogas in Page AZ and if anyone has done it, would like to try, once I get my license, to visit Monument Valley in the winter, in the RV-12. Mesquite NV might also have possibilities or Cedar City, UT. Kayenta, AZ 0v7, looks promising too.
 
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I flew my Cherokee up to Cal Black Memorial (U96) near Monument Valley two years ago. The couple who maintain the airport were so happy to see another face they followed me around chattering about everything that crossed their minds. They were 50 miles from the closest berg and looked like shut-ins!😝
 
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