ANYONE RUN SEF FUEL PRE- MIX ?( is it worth the extra $ )

[Eric106]

I have three cases of SEF50 on the way. I did research on the big 3, as it were, and decided that the SEF was the best bang for the buck. I figure they're all pretty much the same regarding lack of ethanol and shelf life; the octane game I think is a little different.

SEF and Stihl Motomix both express their octane ratings as R+M/2, also known as the AKI, anti knock index. That's what you see at the pump in the U.S., and what's referred to in most owners manuals. Trufuel uses only the 'R' (RON - research octane number) potion of that formula. You can Wiki it and do the math, but the worst case scenario "pump" octane level for Trufuel is 87. The best case scenario could indeed be 92, as they advertise.

The thing with Trufuel is, I'm not sure what the 'pump' octane could be (87-92). And that may be why it's the least expensive option. Motomix is too expensive anyway I looked at it, so that left me with SEF, which appears to be closer in price to Trufuel.

I didn't buy the SEF for daily use, but rather as a "just in case". For now, I have a close source of Shell 93 octane E0 gas when I need it. I try to keep a couple of cans (formally Trufuel) in each power box for backup, or grab and go situations.

This got me curious as I have used some Trufuel from Lowe's or Home Depot for convenient long term storage and began to wonder if it met Stihl's fuel recommendations for my saw. I know Stihl recommends 89 octane (AKI or R+M/2) but Trufuel only specifies the RON at 92 (now they say 92+). As noted above, a 92 RON could equate to only an 87 AKI worst case, which would not meet Stihl's recommendations.

After some searching I found a page on Stihl's corporate site, not on their USA site, about fuel and oil mix recommendations. The page can be viewed here. On the page, under the " Information about petrol" section it states "Always use high-quality petrol with a minimum octane number of 90 RON (we recommend using unleaded to protect your health and the environment)." So it seems that the 92+ RON of Trufuel exceeds the minimum requirements of Stihl for their equipment.

Hope this is interesting/useful to someone.


-Eric

 

[o8f150]

i cleaned up the 372 today and figured since it was empty i went ahead and put about a 1/4 can of the tru fuel in,,, i really don't think throttle response was a bit better,, i run it for a few minutes just to get the fuel in the carb good,,, i know it did have a different smell to it,, as far as running it all the time,, no,, not for what this stuff costs unless i was only using a couple of tanks a year,, but i am using more then 3 gallons a year,,,almost forgot,,, i put some in my weedeater since i put it up dry last year,, it started ok but i had to lean it out

 

[Eric106]

I used Shell 93 octane for years with Amsoil Saber but switched to Belray H1R about a year ago mixed at 40:1 and a shot of Startron without any problems. Just recently i found Sunoco 260 GTX 96 octane E free close to me so i'm using that now. I'm sure the canned fuel is great stuff but it sure isn't cost effective.

I wish I could find a convenient source of Sunoco 260 GTX. If so I would probably run it in all the small engine stuff and the motorcycle. It is definitely the most cost effective specialty fuel. However, the closest place only sells it by the 55 gal drum and I don't need that much at a time. It looks like there may be some e-free gas stations nearby so I'll brobably get some of that and test it to make sure.

When I was in the high desert of Southern California where it is incredibly dry all the time and humidity is essentially nonexistent, I never had a problem with ethanol in the gas. Now that I'm in the Southeast on the Gulf Coast where the humidity is crazy high year round, I have issues. With in a couple months of being here I had to tear the carb out of my bike and clean the corrosion out of the float bowl. I had it apart not too many months before in CA because it got some dirt stuck in one of the jets and it was pristine inside. I move here, it's parked for a coupe months and it won't run right. Tear it down and the brass jets are growing green fuzz.

Ethanol in the gas is certainly not the culprit in every case but it definitely is in some cases.


-Eric

 

[KenJax Tree]

I wish I could find a convenient source of Sunoco 260 GTX. If so I would probably run it in all the small engine stuff and the motorcycle. It is definitely the most cost effective specialty fuel. However, the closest place only sells it by the 55 gal drum and I don't need that much at a time. It looks like there may be some e-free gas stations nearby so I'll brobably get some of that and test it to make sure.

When I was in the high desert of Southern California where it is incredibly dry all the time and humidity is essentially nonexistent, I never had a problem with ethanol in the gas. Now that I'm in the Southeast on the Gulf Coast where the humidity is crazy high year round, I have issues. With in a couple months of being here I had to tear the carb out of my bike and clean the corrosion out of the float bowl. I had it apart not too many months before in CA because it got some dirt stuck in one of the jets and it was pristine inside. I move here, it's parked for a coupe months and it won't run right. Tear it down and the brass jets are growing green fuzz.

Ethanol in the gas is certainly not the culprit in every case but it definitely is in some cases.


-Eric

The 260 GTX I get comes from the pump at the gas station it used to be Turbo Blue leaded 110 octane but recently changed to GTX.

 

[zogger]

i cleaned up the 372 today and figured since it was empty i went ahead and put about a 1/4 can of the tru fuel in,,, i really don't think throttle response was a bit better,, i run it for a few minutes just to get the fuel in the carb good,,, i know it did have a different smell to it,, as far as running it all the time,, no,, not for what this stuff costs unless i was only using a couple of tanks a year,, but i am using more then 3 gallons a year,,,almost forgot,,, i put some in my weedeater since i put it up dry last year,, it started ok but i had to lean it out

Are you able to get non ethanol fuel in your area?