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None ethanol fuel

B

backcountry

Well Known Member
The only non-ethanol fuelsupplier I know here in the south side of the Houston area is Buckys.
Previously, they supplied both 87 and 92 octane. Presently they now only supply one grade 90 octane.
Has anyone had any experience of operating with this fuel?
Rotax 912ULS specification is 91 octane. Fuel suppliers tries to error on the high side to guarantee the rated fuel theysupply..
I guess you could mix the fuel with ethanol 93 octane or just run the engine at a lower power setting.
I tried to stay away from ethanol and lead additives much as possible.
 
You know you can contact the fuel distributor directly & buy in bulk, right? The guy near me sells 93-octane ethanol-free for what I paid for 87-octane ethanol-free at the local gas station. The only issue is the 300-gallon minimum.
 
I have 1500 HOBBS on my io540 RV10 now. It has EFII System 32 and i typically run with 88 to 94 non ethanol. My valves and cylinder show very clean. I replaced #2 cylinder at 1200 HOBBS, but looking back, I should have simply lapped the valve.

I also have an RV14 w/thunderbolt and i only run AVGAS in it. Even though the motor only has 70 TT, the oil isn’t much cleaner than my 1500 hr RV10 IO540 at oil change time.
 
Keep it simple and safe, Run the fuel specified in the engine manual for your engine.
Don't over think it! Run 100LL with a touch of decalin, Vans has been doing it for years
in their RV12s.
 
When I bought my -12 (already flying) back in 2021, I was coming off an aviation hiatus of 20 years. Before that my life consisted of Jet A and the word Rotax meant you might die behind it (tongue in cheek) ;) Fast forward 20 years to 2021.

I emailed Vans directly as all the airport experts were on me about not running clear fuel and were ruining my happiness. I figured, why not ask the guys that designed it.

Here's the answer I got and it has worked just fine for the last 400+ hours. When on the road I use 100LL with Decalin. I agree with jetguy... keep it simple, fly and have fun. I'm not pushing anything in particular, just trying to provide more info. Cheers!



"On Tuesday, September 14, 2021, 01:11:09 PM PDT, Support <[email protected]> wrote:


Russ



We almost exclusively run standard auto fuel with ethanol in our factory demonstrator.



The RV-12 has been designed from day one with the use of up to 10% ethanol being approved as the Rotax engines allow this and in most cases is preferred. The fuel system has also been designed in a way that vapor lock should also not be a problem. The only times I have seen vapor lock present itself is in the spring time when temperatures are rising but service stations are still exhausting some winter blend fuel reserves. Or a plane has sat for a few months having been filled in the winter time with winter blend and holding over into the spring/summer. Another reason one may get a vapor lock is if the pilot/owner installs a on/off switch for the pump or pulls the fuse in flight. The fuel pump constantly running ensures good circulation of fuel back to the tank preventing the chance of vapor lock.



Sterling"
 
Jetguy said:
Keep it simple and safe, Run the fuel specified in the engine manual for your engine.
Click to expand...
Rotax specifies unleaded 91 or higher with less than 10% ethanol.

Personally I now reside in a high humidity locale so less ethanol is better. The station where I purchase the 93 octane "less than 10%" unleaded has never had more than 5.48% ethanol via testing over a three month period. Thus, even on the highest test day that leaves under 2% worst case scenario when blended with 14 gallons of non-ethanol.

When I know that I will be burning through the entire tank in one flight I don't mess with non-ethanol at all.
 
Jetguy said:
Keep it simple and safe, Run the fuel specified in the engine manual for your engine. Don't over think it!
Click to expand...
I agree with that part! 91E10 is approved by both Rotax and Van's.

The official word from Van's in SB 13-3-21 is:
We recommend that RV-12 owners use premium auto gasoline without ethanol if practical, per the Rotax operating instructions. 100LL is approved but requires a different and more laborious maintenance schedule for the Rotax. Given the lack of issues with our company airplanes, and in the current fleet, we believe that 10% ethanol premium car gas is preferable to the use of 100LL, provided appropriate precautions are taken and the operator is aware of the potential issues.
Click to expand...
 
Jetguy said:
Keep it simple and safe, Run the fuel specified in the engine manual for your engine.
Don't over think it! Run 100LL with a touch of decalin, Vans has been doing it for years
in their RV12s.
Click to expand...
To some degree this advice is contradictory to itself. I agree 100% about running the fuel specified. The engine manual for the 912is does not recommend the use of decalin, it never has. There was a period of time where the documentation included a note that they have not observed problems from the use of additives but a recommendation was not made. In the current documentation that note has been removed and Rotax no longer references additives at all. If you keep it simple and run the fuel as specified, it's straight 100LL and follow the appropriate service intervals. Decalin is conventional wisdom, but it is not specified by Rotax.

Removing the note is a recent change to the documentation so I have included the operators manual and appropriate fluids SL here.
 

Attachments

The engine is fine with 10% ethanol but the airframe may not be. I ran into this years ago with a 912 powered a/c. The owner couldn't understand why he had multiple fuel leaks after he started using 92 octane auto gas with ethanol. For years he had been using 100LL (uncertain Decalin)
 
sansoneservices said:
The engine is fine with 10% ethanol but the airframe may not be. I ran into this years ago with a 912 powered a/c. The owner couldn't understand why he had multiple fuel leaks after he started using 92 octane auto gas with ethanol. For years he had been using 100LL (uncertain Decalin)
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You are correct the metal in the engine may be able to handle ethanol quite well however seals, o-rings, fuel tanks, and other materials will be damaged, if not compatible.
I have an STC that allows auto gas in my C-172 except ethanol is not allowed. If ethanol is used in this Aircraft, it could be quite expensive with seals beginning to leak all over the place and that would be quite expensive.
On our field here we had early model Bonanza with an auto gas STC and accidentally received ethanol in a fill up and the results were horrible causing leakage all over the place, fuel cells and so forth.
I’d say be careful knowing all components need to be compatible with ethanol not just the engine itself.
 
backcountry said:
The only non-ethanol fuelsupplier I know here in the south side of the Houston area is Buckys.
Previously, they supplied both 87 and 92 octane. Presently they now only supply one grade 90 octane.
Has anyone had any experience of operating with this fuel?
Rotax 912ULS specification is 91 octane. Fuel suppliers tries to error on the high side to guarantee the rated fuel theysupply..
I guess you could mix the fuel with ethanol 93 octane or just run the engine at a lower power setting.
I tried to stay away from ethanol and lead additives much as possible.
Click to expand...
I have been using non-ethanol 92 grade fuel in my Rotax 912iS engine from the south side of Houston for a few years.
The oil stays clean longer and no carbon deposits.
 
FYI: simple test for ethanol..
hobby test tube, Mark it @1/3 with a felt tip marker, fill with water to your mark, fill the remaining 2/3 with fuel and shake. The water quickly settles at the bottom and if it's ABOVE your mark that's the ethanol that combined with water.. Most of us already know this, just wanted to mention how quick and easy it is. OFTEN I find pumps dispensing ethanol when labeled ethanol free... You can also figure the percentage of ethanol with marks on your test tube for 10% and 5% ... or you can buy a test kit from one of our aircraft suppliers
 
sansoneservices said:
FYI: simple test for ethanol..
hobby test tube, Mark it @1/3 with a felt tip marker, fill with water to your mark, fill the remaining 2/3 with fuel and shake. The water quickly settles at the bottom and if it's ABOVE your mark that's the ethanol that combined with water.. Most of us already know this, just wanted to mention how quick and easy it is. OFTEN I find pumps dispensing ethanol when labeled ethanol free... You can also figure the percentage of ethanol with marks on your test tube for 10% and 5% ... or you can buy a test kit from one of our aircraft suppliers
Click to expand...
Thanks - indeed I'm aware of this test, and I've done it many times to confirm that fuel from a particular source is "ethanol free". The challenge is that you have to do it each time, which means pumping a bit, mixing it with water, going in to pay, waiting for the water and the fuel to do their thing, and then if all is ok, pumping, and paying again.

I've seen cases where someone "guaranteed" that their MOGAS had no ethanol, but for some reason my fuel cap o-rings swelled.... 🤔 This doesn't happen with 100LL or UL91 or MOGAS with no ethanol (or other undesirable aromatics).

What would be nice is something like a pH strip that immediately changes color if it detects ethanol.
 
rv8ch said:
Thanks - indeed I'm aware of this test, and I've done it many times to confirm that fuel from a particular source is "ethanol free". The challenge is that you have to do it each time, which means pumping a bit, mixing it with water, going in to pay, waiting for the water and the fuel to do their thing, and then if all is ok, pumping, and paying again.

I've seen cases where someone "guaranteed" that their MOGAS had no ethanol, but for some reason my fuel cap o-rings swelled.... 🤔 This doesn't happen with 100LL or UL91 or MOGAS with no ethanol (or other undesirable aromatics).

What would be nice is something like a pH strip that immediately changes color if it detects ethanol.
Click to expand...
Yes a strip of some sort would be great. My wife is a nurse, supplies me with free needles for quickly filling the test tube to the mark. The gas eventually eats up the seal
 
rv8ch said:
I've seen cases where someone "guaranteed" that their MOGAS had no ethanol, but for some reason my fuel cap o-rings swelled.... 🤔 This doesn't happen with 100LL or UL91 or MOGAS with no ethanol (or other undesirable aromatics).
Click to expand...
I wonder if it was winter fuel loaded with aromatics, such as butane.
 
Rotax now suggests using their XPS oil instead of adding Decalin to 100LL. XPS replaces Aeroshell Sport 4.
 
docjjrmd said:
Rotax now suggests using their XPS oil instead of adding Decalin to 100LL. XPS replaces Aeroshell Sport 4.
Click to expand...

This reads like you think Rotax somehow associated the Sport 4 with Decalin and the use of leaded fuels. This is not the case, but maybe you mean something else.

Service intervals with both oil products are the same, and in neither case was an allowance made for the use of any scavenging additive with leaded fuel.
 
N8DAV8R said:
This reads like you think Rotax somehow associated the Sport 4 with Decalin and the use of leaded fuels. This is not the case, but maybe you mean something else.

Service intervals with both oil products are the same, and in neither case was an allowance made for the use of any scavenging additive with leaded fuel.
Click to expand...
Sorry if it came out that way. XPS was developed with leaded fuels in mind and when used, negates the need for Decalin as an additive. The release of XPS coincided with the change in documentation you posted above. You are correct in that service interval is the same for both oils and use of 100LL requires a shortened interval.

From the XPS data sheet
"APPLICATION
Formulated for Rotax powered aircraft using leaded or unleaded fuel. Not recommended in automotive applications with catalytic after treatment systems.: This oil is only tested and released for use with a specified range of ROTAX® aircraft engine types. For further information which type of oil to be used for your engine type see our current relevant Service Instruction SI-915 i-001,SI-916 i-001,SI-914-019,SI-912-016,SI-912i-001 Selection of suitable operating fluids for Rotax Engine Type 916 i (Series), 915 i (Series),912 i (Series), 912 and 914. Our shelf life recommendation is 5 years in an unopened container stored in a temperature and humidity controlled environment."
 
docjjrmd said:
Sorry if it came out that way. XPS was developed with leaded fuels in mind and when used, negates the need for Decalin as an additive. The release of XPS coincided with the change in documentation you posted above. You are correct in that service interval is the same for both oils and use of 100LL requires a shortened interval.

From the XPS data sheet
"APPLICATION
Formulated for Rotax powered aircraft using leaded or unleaded fuel. Not recommended in automotive applications with catalytic after treatment systems.: This oil is only tested and released for use with a specified range of ROTAX® aircraft engine types. For further information which type of oil to be used for your engine type see our current relevant Service Instruction SI-915 i-001,SI-916 i-001,SI-914-019,SI-912-016,SI-912i-001 Selection of suitable operating fluids for Rotax Engine Type 916 i (Series), 915 i (Series),912 i (Series), 912 and 914. Our shelf life recommendation is 5 years in an unopened container stored in a temperature and humidity controlled environment."
Click to expand...

I think a lot of that copy from Rotax is meant to get people comfortable for the use of synthetics and leaded fuel at all. With the Mobile 1 debacle from the 90s it has a giant stigma in aviation...so it's a big deal for Rotax to endorse a synthetic fuel in an application where there will be lead.

It's odd to me that this somehow get construed as though Rotax was recommending Decalin before. That's the implication I think we should be careful about because Rotax has never suggested it no matter what oil you were using.
 
N8DAV8R said:
I think a lot of that copy from Rotax is meant to get people comfortable for the use of synthetics and leaded fuel at all. With the Mobile 1 debacle from the 90s it has a giant stigma in aviation...so it's a big deal for Rotax to endorse a synthetic fuel in an application where there will be lead.

It's odd to me that this somehow get construed as though Rotax was recommending Decalin before. That's the implication I think we should be careful about because Rotax has never suggested it no matter what oil you were using.
Click to expand...
I don't doubt that is true. And yes it seems if Decalin was gospel for some users yet never tested or suggested by Rotax.
 
dbhill916 said:
I've never heard of XPS. Thanks for the info. Who stocks it?
Click to expand...
The three Rotax parts suppliers. It is a Rotax product. So Lockwood, Motive Aero, and Advanced Powerplant Solutions are your choices. Not unreasonable in price and because only 3 or so liters is used at a time not a bank breaker
 
dbhill916 said:
I've never heard of XPS. Thanks for the info. Who stocks it?
Click to expand...
Rotax distributors. I got some from Lockwood for my engine’s initial 25 hours, and plan to switch to Aeroshell at first oil change (less expensive and more widely available than XPS).
 
csmith3603 said:
I have been using non-ethanol 92 grade fuel in my Rotax 912iS engine from the south side of Houston for a few years.
The oil stays clean longer and no carbon deposits.
Click to expand...
Can you provide me the supplier of the non-ethanol 92 octane fuel on the south side of Houston. That would truly solve my problem.
 
I suggest you buy Mogas from a Top Tier supplier… I have been buying 93E10 from Costco now with over 1000TT on my 12. Costco is a Top Tier supplier. No problems…. I was on a business trip once and sat next to petroleum engineer on the flight… he was telling me how discount refineries use “slop” oil to distill auto fuel. Slop oil is culled from the interface of different oil products in a pipeline. Might be sending kerosene followed by heavy crude. Where the two products intermix is culled into a slop tank and less reputable refineries used it to make auto fuels.
 
Piper J3 said:
I suggest you buy Mogas from a Top Tier supplier… I have been buying 93E10 from Costco now with over 1000TT on my 12. Costco is a Top Tier supplier. No problems…. I was on a business trip once and sat next to petroleum engineer on the flight… he was telling me how discount refineries use “slop” oil to distill auto fuel. Slop oil is culled from the interface of different oil products in a pipeline. Might be sending kerosene followed by heavy crude. Where the two products intermix is culled into a slop tank and less reputable refineries used it to make auto fuels.
Click to expand...
I’m no chemical engineer, but I don’t understand the issue with using slop. The raw product needs to be distilled and meet the applicable standards to be sold. Are you saying these entities are deliberately selling product that does not meet spec?
 
mstrauss said:
I’m no chemical engineer, but I don’t understand the issue with using slop. The raw product needs to be distilled and meet the applicable standards to be sold. Are you saying these entities are deliberately selling product that does not meet spec?
Click to expand...
seems to me that top tier gas has more additives like PEA to help keep your combustion area cleaner.
 
Not sure if it is the same all over the country, but the 2 Costcos I shop in PA get their 93 provided by Sunoco and usually get at least one fill a day of fresh fuel. I also test it and it is usually 2-4 percent ethanol.
 
backcountry said:
The only non-ethanol fuelsupplier I know here in the south side of the Houston area is Buckys.
Previously, they supplied both 87 and 92 octane. Presently they now only supply one grade 90 octane.
Has anyone had any experience of operating with this fuel?
Rotax 912ULS specification is 91 octane. Fuel suppliers tries to error on the high side to guarantee the rated fuel theysupply..
I guess you could mix the fuel with ethanol 93 octane or just run the engine at a lower power setting.
I tried to stay away from ethanol and lead additives much as possible.
Click to expand...
See pure-gas.org for a list of 17,733 sellers of ethanol-free fuel in the US. From the map there you appear to have quite a few sellers around Houston. Generally, wherever boats are popular, you will find retail sellers of real gasoline. Note that ethanol may not be pumped through pipelines due to its corrosive nature, therefore all fuel terminals have ethanol-free fuel. They mix it there with ethanol and ruin it. Try contacting your local terminals and fuel distributors to see if they will get you what you need. It is the best aviation fuel for piston aircraft. 70% or more of legacy piston aircraft can operate with it under an inexpensive STC whcih in most cases is nothing more than a sticker. All modern aircraft powerplant manufacturers design their engines to operate on ethanol-free, lead-free fuel, so yes, it is an excellent aviation fuel. Rotax is the world's largest producer of aircraft engines and they strongly recommend operating their engines on autogas, of the correct AKI rating, of course.
 
[email protected] said:
See pure-gas.org for a list of 17,733 sellers of ethanol-free fuel in the US. From the map there you appear to have quite a few sellers around Houston. Generally, wherever boats are popular, you will find retail sellers of real gasoline. Note that ethanol may not be pumped through pipelines due to its corrosive nature, therefore all fuel terminals have ethanol-free fuel. They mix it there with ethanol and ruin it. Try contacting your local terminals and fuel distributors to see if they will get you what you need. It is the best aviation fuel for piston aircraft. 70% or more of legacy piston aircraft can operate with it under an inexpensive STC whcih in most cases is nothing more than a sticker. All modern aircraft powerplant manufacturers design their engines to operate on ethanol-free, lead-free fuel, so yes, it is an excellent aviation fuel. Rotax is the world's largest producer of aircraft engines and they strongly recommend operating their engines on autogas, of the correct AKI rating, of course.
Click to expand...
Yes, I also have an STC for for my C-172. So I use none ethanol in both. The C-172 only needs 80 octane so it has more option but I try to but the higher octane so I can use it in both aircraft.
91 non octanes are playing with the hard t.com Find.
 
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