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SB 13-3-21 Ethanol in Gasoline

Is anybody clutching their chest on this one? I've got 600+ hours now, all on COSTCO av fuel with no issue. I fly 2x week minimum and just put new hoses on. I did not see anything new to worry about but am curious if anyone is changing their fuel regime.
 
Does anyone knows of non-ethanol 93 octane fuel located south side of Houston Texas?
Bucee’s used to have it however they lowered their octane to 87.
 
Rotax fuel

If you have a 912UL you can use 87 octane or higher and if you have a 912ULS use 91 octane or higher.

Good luck
 
BP

For what it's worth: someone told me some years ago that after further investigation only BP puts very little ethanol in it's gasoline - I buy BP 98 for my bird since then (Europe, ULS engine)
 
For what it's worth: someone told me some years ago that after further investigation only BP puts very little ethanol in it's gasoline - I buy BP 98 for my bird since then (Europe, ULS engine)

You can buy inexpensive ($10USD) test kit to determine % alcohol in auto fuel...
 
I use Costco premium exclusively except when on trips. Every 6 gallon jug is tested for alcohol content, it always runs between 6-8%. On trips if I can find auto gas close to the airport I always test it before pouring it in. The plane during my ownership has flown 725 hours in the past 35 months, a little north of 3000 gallons. I am based in SoCal with typically very HOT summers. Only once I suspected a situation similar to vapor lock and can't be positive. I always purge the fuel system with the electric pump before starting. I believe that is very important to pushing the heat soaked fuel out and keeping cooler fuel in the lines to the carburetors.

I have my Dynon set to alarm me if the fuel flow drops below 1.8 GPM. If I was to get this alarm it would mean a potential vapor lock situation. In testing (on the ground) at full power and turning the fuel valve off the engine will run for 15 - 20 seconds. In theory if I got the low fuel flow alarm I would have 15+ seconds to make a plan for landing, that's a lot of time in an emergency.
 
For what it's worth: someone told me some years ago that after further investigation only BP puts very little ethanol in it's gasoline - I buy BP 98 for my bird since then (Europe, ULS engine)

Depending what "very little" is, it may not be any better, according to this source anyway - Fact Sheet | The Consumer and Fuel Retailer Choice Act

The plot is vapor pressure of gasoline vs alcohol concentration, with a reference line of pure gasoline at 60kPa.

15% Ethanol is actually slightly better than 10%.
 

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For dummies like me, which VP is better?

Depending what "very little" is, it may not be any better, according to this source anyway - Fact Sheet | The Consumer and Fuel Retailer Choice Act

The plot is vapor pressure of gasoline vs alcohol concentration, with a reference line of pure gasoline at 60kPa.

15% Ethanol is actually slightly better than 10%.

For purposes of a Rotax 912, is higher or lower better? Thanks.
 
For purposes of a Rotax 912, is higher or lower better? Thanks.

It's not so much the ethanol. Ethanol is bad - don't get me wrong - less is more, by sticking with PM it is usually less normally anyways...but imho - It's the winter gas blend vs summer gas blend. RVP.

https://www.eia.gov/todayinenergy/detail.php?id=11031

Many RV12 owners run a blend of 100LL and winter premium auto gas, shift to pure premium auto gas when summer blends hit.

Putting the higher pressure aux fuel pump in helped me a lot with fuel pressures - i think it became a kit standard a few years back.

Also the Rotax 912 engine driven pump is subject to the 5-year replacement time frame too - even the new pumps.
 
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