Aviation fuel

[Williedrifter]

Anyone run aviation fuel in your outboards? The 101 octane stuff. I know when I was in Alaska the same gas was used in the boats as the planes with no adverse affects. I even have the same Yamaha 40MSHX motor as used in most Alaska fish camps. Condensation and Ethonal are geting me down, and yes i use Sta-bil.

[BassinFever]

Running Av Gas can actually cause ring coaking and your engine will not have the power that it will with 87! However it will sound smoother due to the slower combustion!!

[Bobberman]

Here is a list of place with non ethanol fuel, just pull up and fill, much easier than messing with av gas.

Looks like there is one in your town

http://www.boatoregon.com/OSMB/news/...thanolList.pdf

[baitsauce]

Originally Posted by BassinFever

Running Av Gas can actually cause ring coaking and your engine will not have the power that it will with 87! However it will sound smoother due to the slower combustion!!

What is "ring coaking"?

[Highmark]

Thanks for the List. I see that Fischers mill has it. I just called them
there price per gal is 2.339. Fair price. I guess. Any way they are
close to me.

[nobrownline]

The owners manual on most outboards say use 87 octane. Av gas has additives to help it at elevation.

[lucky2]

100LL avgas contains tetraethyl lead and a suspension agent to keep the lead from fouling spark plugs. If your combustion temperature is below 800F (as it frequently is in marine engines) the lead will accumulate on valves, pistons, rings, plugs, and etc causing a condition known as coking.
It is a greyish black hard deposit that is mostly lead oxides. You are far better off running pump 87 in most marine applications.

[baitsauce]

I know it's not a marine engine but I used to run AV gas in my go-fast-car with no problems. Infact I had to, for the higher octane and valve lubrication. However, it was only run either on a really nice day or going in a 1320ft straight line very fast.

(Sold it years ago when the fishing bug hit)

//

[lucky2]

I use it in my go-fast drag boat. It's great for those kinds of applications, not so good for outboard use.

[Highmark]

This is a little funny. I have a lot of friends that have there own planes.
Av gas is so expensive, they buy reg gas to put in there planes to bring down the price per hr to fly. I personally would not use it, for one reason
it's formulated to engines of High compression that operate at altitudes
high compression engines need 92 or higher octane to run cooler, or it will
take out the pistons and rings. 87 octane gas will detonate at
5000 ft in a engine with 140 pounds of compression at about 1200 deg. but 100 octane gas in the same engine will fire around 1400 deg.
that will burn down your engine. so if you run that same gas at sea level.
you are setting your self up for a melt down.
And one more reason, av gas runs around 4 to 5 bucks a gallon.
and most aircraft engines run at a constant rpm or 100 percent during flight.

The guys that are running it in there drag cars. do it in way that keeps
a lot of gas going in to engine to keeps it cool. most engines that melt down do it at a mid range. this I have learned over the years from setting up and racing snow machines.
you set up an engine to run as close to 1400 deg at the elevation you are racing at or at the barometric pressure is at the time you are setting that engine up that day.

you use octane to compensate for loss of oxygen at altitude.

[Willie Ketchum]

No use in two strokes with their low compression. Slower combustion will equal less power. High compression four strokes, say above 11-12:1 can benefit, thus the use in aircraft, race cars and drag boats. All stock outboards will run on 87.

[Beaglehunter]

Originally Posted by Bobberman

Here is a list of place with non ethanol fuel, just pull up and fill, much easier than messing with av gas.

Looks like there is one in your town

http://www.boatoregon.com/OSMB/news/...thanolList.pdf

Thank you Bobberman. I just had to take the carb off my T-8 and clean to get it to run. I will be going to the local non blended gas station from now on!!!

[Williedrifter]

Wow good info. I am a believer for many if not all the reasons above. I appreciate the list of non blended retailers as well. I went down to the Garibaldi Marina this afternoon and filled my tanks. I should be good to go again, with cleaned carbs, serviced fuel water separator, new fuel filter, and most importantly NON-ethanol fuel!

[baitsauce]

You'd make it out and back to the docks in a jiffy!

Admit it; you've at least thought about it!!

//

[fishkisser]

Darn right I have given it some thought ...
But will the turbine bearings take the extended RPM's ? ...

[Just-in-Time]

AV gas will not freeze

pump gas will freeze at extreme temps