Fuel type used????

[waterboy]

Good information in all of these posts, very informative so you can make a good decision about how you want to run your engine.

Holy crap though, these posts are like a Ford vs Chevy, box anchor vs any other anchor, Yamaha vs Rotax, etc.

I'll just wave the flag on this Friday afternoon and y'all be safe on the water this weekend whatever your burning!!!

 

[JetTech72]

For the Rotax supercharged engines I would not pay extra for NON-Ethanol gasoline as the powerpack uses Automotive components, O2 sensors, Fuel pump, injectors, etc... all designed to operate on E10. This is not a mid 90's carburated engine.
I would definitely pay a little extra for higher octane (91+), especially in the middle of the summer when air & water temperature are at there highest.
Rotax supercharged engines, as many high performance engine, use knock sensor to monitor combustion happiness & protect the engine. Therefore the management system will drop the ignition timing if knocking events are being recorded, thus resulting in easily 300 rpm drop.

As far as 93 octane fuel being low on ethanol, this will vary from location to location, but from experience it's normally the opposite as Ethanol alone has an Octane rating of about 100, thus giving a natural octane booster to the gasoline.
Last time I measured our local gasoline supplier, the 93Oct averaged 10.3% Ethanol.

 

[swatski]

Great discussion!
Unfortunately for some of us, especially here in Midwest, we may not have access to non-ethanol fuel. Impossible to get it around St. Louis, for one.
And that is where a point-counterpoint discussion can be really helpful to sort through the options one faces.

One think I wonder about is exactly what happens when gas gets "old". Or - does it? Water/fuel separation in EtOH fuels is one thing and it happens, obviously, but is there more to "old" fuel problems than that?

 

[Big Shasta]

Great discussion!
Unfortunately for some of us, especially here in Midwest, we may not have access to non-ethanol fuel. Impossible to get around St. Louis, for one.
And that is where a point-counterpoint discussion can be really helpful to sort through the options one faces.

One think I wonder about is exactly what happens when gas gets "old". Or - does it? Water/fuel separation in EtOH fuels is one thing and it happens, obviously, but is there more to "old" fuel problems than that?

Google "Ethanol Phase Separation" Even if you remove the water with a separator, you have removed a significant amount of octane on the fuel remaining. since the ethanol is a higher octane and used to bring up the rating of the fuel it's mixed with. This is the biggest negative....the fuel components are designed to handle the corrosive properties of ethanol, it's fuel that sits that becomes a problem.

Fill a small glass jar with e10 fuel and leave it sitting in your garage open to the air. See how long it talks for it to have visible separation. If you live in a low humidity climate, you may not have an issue in air but remember, you're on the water where plenty of wet air is present.

Oh it appears some have hurt butts lol

Not sure if you're talking about my posts but just in case, I'm not butt hurt at all. Just trying to help folks out. Lots of people don't realize the risks and just go with it. Marine mechanics, small engine mechanics, anyone who works on engines not used daily and refreshed with new fuel regularly are loving it. It's putting their kids through college with big repair bills. Drop in to a mower repair shop or boat mechanics shop and talk to one about fuel issues they see.

 

[smashedheadcat]

@JetTech72
..automobile fuel tanks are not vented and are sealed...no way for humidity or water molecules to enter.

Not true. All fuel tanks in automotive applications are vented, just like they are in boats.

 

[swatski]

@Big Shasta No, my latest post was not directed at you. The person it was directed at knows who they are.

LOL - not me!

 

[shift_nashville]

87 / 89

service in the ___ is a calling only a few will answer.

NSDQ my friend.