mogas/ethanol
 

I fly rv6 with a 0320 e2d in the NE .I believe most of the NE states now blend 10% ethanol ,can I run the fuel or do I have to modify fuel system. What does FAA say about experimental and fuels ?? Any help would be appreciated. :confused: Gary

Ethanol in mogas
 

The main issue with having ethanol in fuel is the effect it might have on any rubber and plastic within the fuel system. Ethanol can cause a lot of rubber gaskets, o-rings, and hose to swell and disintegrate if they are not rated to work with ethanol/alcohol.

To ensure your fuel system can handle ethanol, you'll need to check with the manufacturer of all the components from your fuel cap to your intake system if they have been tested to be compatible with ethanol. Fuel pumps, hoses, gaskets in the carburator, and o-rings are the main possible problem areas. Your RV fuel tanks probabably do not have a rubber bladder, but a previous owner may have sloshed with something that is not happy with alcohol.

This all assumes of course that your engine is rated for mogas.

Since your aircraft is experimental, the FAA has delegated responsibility to you to designate an appropriate fuel for your aircraft. If your POH/AFM does not include mogas as an approved fuel, I'm not sure if it is required to add this, or if Phase 1 testing is required. Those would be good questions for people that know what they are talking about, unlike me.

Vapor Lock
 

In addition to hose and gasket issues, the chance of vapor lock is significantly increased with fuel containing ethanol. Auto fuel STC's specifically prohibit the use of auto fuel containing alcohol for these reasons.

John

RV-9 wings / qb fus

I don't really intend to run mogas, but I'm very curious about the concern over ethanol in aviation fuel. Can anyone point me to some more reading on the subject? (preferably internet, of course)

Peterson Mogas STC
 

another good Mogas article
 

http://www.eaa.org/education/fuel/autogaspart2.pdf G

BTU per gallon
 

Just a reminder for those that snoozed during chemistry class, alcohol has less energy per gallon than gas (122,000 BTU/gallon for gas, 84,000 BTU/gallon for ethanol).
While this may not be an issue at 10% blends, fuels like the currently hyped E-85 with significant proportions of alcohol will reduce your range enough to notice, about 27 percent. Unless the carburator jets or fuel injectors are modified, takeoff power will also be noticeably reduced, but the power produced without mods may be OK for cruise flight.
I'm sure most of the serious mogas junkies already know this.

Has anyone noticed any kind of disclaimer or documentation on the gas pumps that the mogas contains 10% alcohol? Or are we going to have to do the test recommended by Petersen STC?

http://autofuelstc.com/autofuelstc/pa/ethanoltest.html

Here is another thread with some comments on this issue. Hecilopter has some interesting links on ethanol use.
http://www.vansairforce.com/communit...ead.php?t=8229

Proseal?
 

Is there any incident of proseal dissolving and clogging up the lines?