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Hawksinkalispell
08-03-2010, 02:54 PM
With all the Ethonal fuel in the pumps these days who is using fuel additives, what kind, is there a big difference in performance?

Where's the place to buy the additives without breaking the bank?

SKADMAN
08-03-2010, 03:17 PM
Good question. I want to know too.

jmac197
08-03-2010, 05:08 PM
I think I got mine at WalMart.




Marine Formula STA-BIL



America's #1 Selling Marine Fuel Additive Brand!
BEST Ethanol Problem Fighter
More than FOUR TIMES the Fuel System Cleaner than in Regular STA-BIL
DOUBLE the corrosion preventer than in Regular STA-BIL
Prevents corrosion from moisture & ethanol-induced water attraction
Improves marine engine performance YEAR-ROUND, not just for seasonal storage

http://www.goldeagle.com/assets/product/Marine-Formula-STA-BIL_8oz_Ethanol_Treatment_22239.jpg
Treats up to 80 Gallons



Part #: 22239



UPC: # 073905 22239 6
Pack: 12/8 fl. oz. (12/236mL)


http://www.goldeagle.com/assets/product/Marine-Formula-STA-BIL_32oz_Ethanol_Treatment_22240.jpg
Treats up to 320 Gallons



Part #: 22240



UPC: # 073905 22240 2
Pack: Pack: 6/32 fl. oz. (6/946mL)

JohnnyB
08-03-2010, 10:16 PM
Ditto here. Use Sta-bil Marine

1985 Skiier
08-04-2010, 09:39 PM
I have an 85 s/s and I use a lead additive and Lucas. Sta-bil if it will sit for a month or more.

1redTA
08-04-2010, 11:06 PM
I'm lucky, I found an ethanol free gas station on the way to the boat ramp. I plan on filling it half and half during the summer and no ethanol for winter storage plus stabil.

1985 Skiier
08-04-2010, 11:39 PM
I heard that small engine repair shops are recomending jetfuel be used in small engines because the new gas is so bad and starts to break down in 30 days. Jet fuel can sit on the shelf in the garage for years like camping fuel (white gas) The FAA does not allow that crap, but we pump it in our boats. My 1985 manual says to run leaded fuel only, If I remember correctly the lead lubricates the valves. Is that correct?

MakeMineaS&S
08-20-2010, 05:03 AM
Wanted to chime in here since I have a ethanol-free gasoline obsession. Sorry to resurrect a dormant thread.

I use 100LL avgas in my boat. Shelf life measured in years, no hot-start/vapor-lock problems since it has a higher evaporation point than mogas, it's leaded, which is called for in the older engines, and it just smells so GOOD when the engine is running.

Fires right up and runs like a champ. Some might argue that 100-octane might be a little "much" for a boat, but the plugs look good and it was designed for engines very similar in operation to ours:

steady-state operation
always under load
fairly low-compression and low-RPM

etc, etc.

The cost isn't an issue since Marina mogas is about 3.70/gal where I'm at, (not sure if it's ethanol-free), and on my airport, (I live on an airport), avgas is 3.95/gal. 25 cents more and I get no ethanol, no vapor-lock, no water in the gas, long-term storage worry-free, cleaner plugs, (I know, it sounds weird, but the engine overall runs cleaner on 100LL, the explanation is beyond the scope of this post, but if anyone cares, I'll expound), and the sweet, SWEET smell of combusted TEL.

And it's 100% legal.

Seriously, if you live near a small FBO airport, stop in sometime and run a tank in your boat. I love it.

This ethanol stuff REALLY pisses me off. I am an aficionado of older motorcycles and cars, and the old fuel systems just don't like this crap. And especially boats, since ethanol is hygroscopic, it's MURDER on engines and carbs.

We need to do whatever we can to get this crap out of our fuel. I live in an area where there are NO non ethanol stations.

Go here and add to the database and try to help fellow enthusiasts out:

http://pure-gas.org/

ETA:

1985 Skiier: I'll bet it's 100LL avgas the people are recommending for use in small engines, boats and off-road vehicle engines. "Jet Fuel" or "Jet A" or "JP-8" or whatever, is basically very near to kerosene. Diesels can run it, (though I think minor setup is involved, maybe not), but a gasser would have a huge problem with it.

Jesus_Freak
08-20-2010, 01:46 PM
...Some might argue that 100-octane might be a little "much" for a boat...

I would be interested in hearing more about those views/theories.

MakeMineaS&S
08-20-2010, 02:41 PM
I would be interested in hearing more about those views/theories.

Sometimes when I mention that I run 100LL in it, people tell me that since the highest grade called for is 93, (valve cover decal says to run 87, 89 or 93 leaded), then anything more than that is a waste of money, and might cause a loss in power, since it'll have a slower flamefront, or otherwise not be "totally combusted" by the time the exhaust stroke starts.

I've never noticed a problem and the boat pulls hard, doesn't knock, runs cool, and I still get as near the advertised top-end as I always have. (45 claimed top-end from an '85, I usually get 42-43 with three or four people in the boat and full gear, and a slightly dinged prop.)

Never heard it here, but from other car/engine guys. I think there's something to it in the sense of the higher octane rating won't "make more power", (like some guys who buy premium or other high-octane gasoline claim), but all the other benefits of avgas make it worth it, to me.

Bert
08-20-2010, 02:46 PM
With all the Ethonal fuel in the pumps these days who is using fuel additives, what kind, is there a big difference in performance?

Where's the place to buy the additives without breaking the bank?

Been using Forte in my gas and diesel engines. Improved mileage since I started using it.
Available at diesel truck repair shops.


http://www.forteuk.co.uk/

Jesus_Freak
08-21-2010, 08:22 AM
Thank you.

Sometimes when I mention that I run 100LL in it, people tell me that since the highest grade called for is 93, (valve cover decal says to run 87, 89 or 93 leaded), then anything more than that is a waste of money...I think there's something to it in the sense of the higher octane rating won't "make more power", (like some guys who buy premium or other high-octane gasoline claim), but all the other benefits of avgas make it worth it, to me.

Yes, I was well aware of this part, and it has been discussed many times on TMC before.

...and might cause a loss in power, since it'll have a slower flamefront, or otherwise not be "totally combusted" by the time the exhaust stroke starts.....

I agree that, as a general rule, we expect a more controlled, homogeneous front with higher octane, which would be why we would buy it. However, what we dont know is just how long we typically have between the time the final volumes of fuel are burned and the time the exhaust port opens throughout the RPM and fuel load range. If we normally have 10 microseconds, and the use of 100 octane versus 87 octane only makes 3 microseconds difference, then who cares. If we normally have 10 microseconds, and the two fuels makes 20 microseconds difference, then we care. Have you ever seen any data on this? If not, I have a friend at GM R&D who might know.

ski_king
08-21-2010, 09:32 AM
I heard that small engine repair shops are recomending jetfuel be used in small engines because the new gas is so bad and starts to break down in 30 days. Jet fuel can sit on the shelf in the garage for years like camping fuel (white gas) The FAA does not allow that crap, but we pump it in our boats. My 1985 manual says to run leaded fuel only, If I remember correctly the lead lubricates the valves. Is that correct?
may be wrong, but isnt jet fuel kerosene-based?

MakeMineaS&S
08-21-2010, 03:02 PM
Have you ever seen any data on this? If not, I have a friend at GM R&D who might know.

Never seen tests of the different burn rates of fuel, though I know it's done all the time, and I can't find any avgas tests online. Maybe my Google-Fu is weak.

However, testing or not, I think it works better than lower-octane fuel, at least in these applications, for the reasons I stated. It runs fine every day in low-rpm, low-compression engines, in a huge variety of temperature and atmospheric conditions that make our boat engines look absolutely pampered and babied. And they don't stall, flame out, burn pistons, knock, or otherwise act untowards (at least not generally, and it's usually not fuel related). It IS FAA-certified for use in aircraft, and to get a fuel past their process is no-joke.

I would like to install EGT sensors and gauges and see if different grades of fuel result in different exhaust gas temperatures, and the effect on power output and delivery, perceived or real.

However, in real world, I notice little difference in actual running performance of the engine between low-test 87 and 100LL and all grades in between. Same top-end WOT, same pull and acceleration, no knocking, but the 100LL is easier to start hot, burns cleaner (the plugs are cleaner), and I don't have to worry about phase separation, water in the fuel, alcohol being harsh on engine and carb parts and breaking down in long-term storage. Not bad for only a quarter more a gallon.

I also think that the "100" designation is a bit of a misnomer, at least compared to how we rate mogas octane.

IIRC, mogas octane is a combination of Research Octane and Motor Octane ratings. IE, high-test is 93, which is a MON of 98 or so, and a RON of like, 90, or something to that effect.

In Europe, They only use MON as far as I know, so you buy "98 Octane" in Europe, but it's the same as "93" back in the States.

I do know that avgas is 94-octane when refined and unleaded, and is called 94UL, for "94 Unleaded". Then they add the TEL and it bumps up to 100 points. Not sure if it's "apples to apples" with mogas or if it's a different designation that is applicable/comparable only to other aircraft fuels, IE: 80LL, 100LL, 100/130, 115/145, etc.

falconjeter
08-21-2010, 03:22 PM
The higher the octane the better, 100LL runs great in any gas engine. I am a aircraft mechanic by trade and can say yes it maybe overkill to go beyond the required octane need but it will not hurt unless it is a catalyzed engine(100 LL has 4 times the lead of regular leaded gas), it also has more BTU rating per gallon so fuel economy will be better. The only concern is that avgas is HIGHly aromatic, this means it evaporates faster, the fumes are more volatile too and this can cause drying out of seal and gaskets not made for this type of fuel. Lead is used to prevent detonation in the cylinders and lower the combustion temp, it also cushion the valves. I have not ran avgas in my boat but I have a 1965 piper Comanche that i spend thousands on avgas for!! Its for sale too if anyone is interested!

MakeMineaS&S
08-21-2010, 03:32 PM
Now from experience, I do know that it evaporates VERY quickly, but I also read that it's formulated with a very high evaporation point, (or at least a more stable one) so that as you go up in altitude, the lower atmospheric pressure doesn't cause evaporation like it would with mogas. Apparently mogas at altitude can cause vapor lock as it evaporates out of the carb bowl and fuel lines. I would presume the mogas STC takes care of that.

I also read that the mogas STC is an absolute no-go with ethanol gasoline, per the FAA, which is why it's not being done often anymore.

Being an A&P, what are your thoughts?

Also, have you seen the new fuel that's being independently tested, G100UL "Ghoul Fuel"? Looks VERY promising, and with the threat of 100LL being phased out in the next few years, I think it's the future. IF the FAA will get off their dead-asses and test it.

Jesus_Freak
08-21-2010, 10:07 PM
...The only concern is that avgas is HIGHly aromatic, this means it evaporates faster,...!

I have not studied the blending of fuels, so I am curious here...by "aromatic" do you mean that it is composed of a larger than normal proportion of specifically aromatic species (benzene, toluene, etc.), or do you just mean that it contains a larger than normal fraction of low boilers (smaller chains or rings)?

DooSPX
08-21-2010, 10:56 PM
I have not studied the blending of fuels, so I am curious here...by "aromatic" do you mean that it is composed of a larger than normal proportion of specifically aromatic species (benzene, toluene, etc.), or do you just mean that it contains a larger than normal fraction of low boilers (smaller chains or rings)?

over my head as usual my friend :o:confused::confused: