RE: Aviation gas

[firefighterjake]

I think this has been brought up in the past . . . but thought I would bring it up again . . . just because I recently was told by some folks working at a local airport that there is a pretty large fine for them if they are caught selling av gas to anyone that doesn't have an aircraft with a tail number . . . not sure if this is just at this airport or all over, but I found it interesting.

Moreover, when I asked a mechanic friend (also a former stock car driver) he confessed that he has used some av gas in his stock car . . . but said the combination of the leaded gas and higher octane would tend to cause the engine to run a bit higher . . . or maybe it was just the octane would cause it to run hotter . . . he personally recommended not running it in any small engines . . . or even putting it in a vehicle.

Thoughts?

---

On a related note . . . these same folks at the airport dropped off two jugs at our training facility yesterday with a 50-50 mix of av gas and Jet Fuel A for use in my training fires . . . however, it appears as though someone came along and saw the blue "Kerosene" jug and the red safety gas can and decided to use them.

Kinda sitting here wondering what will happen if they try to burn the mix in a kerosene heater or in their oil furnace . . . and what will happen if they try to burn the mix of gas in their snowmobile, ATV, car, etc.

 

[Danno77]

No comment on the first part, but OMG on the 2nd part. That is job security right there FFJ!

 

[DMZX]

I owned a Triumph Bonneville that preferred leaded premium. After the leaded gas disappeared from the pump, I sometimes would take the bike out on the tarmac at a nearby airfield and get a tank of AVGas. I could do this because I knew the guy that ran a aircraft service business from a quonset hut out there. I kept the Triumph until 2003 and it would run on unleaded gas after I re-jetted the Amals a couple of times.

That being said, I do not think I would not run leaded gas in any modern engine with an ECU. It would plug up the cat' good and you would probably get a check engine light with several PO17X codes being thrown due to the O2 sensors aft of the cat'. The ECU will try to adjust which may result in misfires (worse case). I do not think it would hurt to run leaded gas in a modern small engine like a lawn mower or chainsaw.

 

[MasterMech]

As a small engine pro, I've been pretty firm in my stance with AvGas in non-aircraft uses. I totally sympathize with folks looking for fuel that won't foul in storage. However I think using AvGas (Unless you happen across some unleaded variety) is a case of where the cure can be worse than the disease. It's not sold at every corner gas station for a reason. 100LL (the most common blend) has anywhere from the same to twice the TEL (lead) in it that 60's era auto fuel did. The only reason leaded AvGas is still available is because older vintage aircraft NEED it to keep valves from chewing themselves apart. The same reason we ran it in past cars, the metallurgy used in the engine parts required the lead deposits from the fuel to control wear. Apparently there is not yet a lead substitute or additive that will satisfy the FAA for aircraft use either.

AvGas is also blended for large displacement, relatively slow-rpm engines operating under heavy load at high altitude and cool ambient temperatures. That sounds just like your saw/trimmer/mower right? Might help prevent carburetor icing in our saws tho... Will it hurt our equipment? Prolly not but I've made the point before about engine exhaust (vaporized lead fumes?) on OPE being in closer vicinity to the operator than automotive or general aviation applications. For those looking for an ethanol-free, high-octane fuel that can be stored longer than pump gas, check out automotive race fuel. It's available in every flavor under the sun including unleaded. VP Racing Fuels has a special small engine blend now but I'm sure it's expensive.

http://www.vpracingfuels.com/sef-94.html

I've been running Regular (87) unleaded 10% ethanol auto fuel in all my equipment with ZERO fuel issues to date. My ATV rarely gets used and sees maybe 1 fill-up a year. The carb still functions like new. I've had the fuel go stale and run poorly compared to fresh, but never the carb eating corrosion I've seen in other cases. All of my other equipment runs perfectly and to date hasn't needed any fuel system work that I can attribute to the fuel itself. I get a lot of work involving small engine fuel systems and I hear ya on the storage issues. But take the proper steps to stabilize your fuel and you can run any grade of automotive fuel in your OPE (Reg, Mid, Prem), save the trip to the airport, and the cost premium for AvGas itself.

 

[bluedogz]

For those looking for an ethanol-free, high-octane fuel that can be stored longer than pump gas, check out automotive race fuel. It's available in every flavor under the sun including unleaded. VP Racing Fuels has a special small engine blend now but I'm sure it's expensive.

http://www.vpracingfuels.com/sef-94.html

I can speak for the quality of VP Fuels from motorcycle racing, as long as you want to put $30-$50/gallon into your chainsaw. I found such fuel only made a detectable difference in a high-compression engine running at very high cylinder temps, and even that was often only measurable on a dynamometer. VP's unleaded product is also oxygenated, meaning relatively short shelf life. IMHO, waste of money in a production engine of any type.

Are we really having this conversation about chainsaws?

OTOH, there is NO smell in the world like the smell of a 2-stroke burning race gas on a cool fall morning. No, not even... that.

 

[Bigg_Redd]

I think this has been brought up in the past . . . but thought I would bring it up again . . . just because I recently was told by some folks working at a local airport that there is a pretty large fine for them if they are caught selling av gas to anyone that doesn't have an aircraft with a tail number . . . not sure if this is just at this airport or all over, but I found it interesting.

Moreover, when I asked a mechanic friend (also a former stock car driver) he confessed that he has used some av gas in his stock car . . . but said the combination of the leaded gas and higher octane would tend to cause the engine to run a bit higher . . . or maybe it was just the octane would cause it to run hotter . . . he personally recommended not running it in any small engines . . . or even putting it in a vehicle.

Thoughts?

---

On a related note . . . these same folks at the airport dropped off two jugs at our training facility yesterday with a 50-50 mix of av gas and Jet Fuel A for use in my training fires . . . however, it appears as though someone came along and saw the blue "Kerosene" jug and the red safety gas can and decided to use them.

Kinda sitting here wondering what will happen if they try to burn the mix in a kerosene heater or in their oil furnace . . . and what will happen if they try to burn the mix of gas in their snowmobile, ATV, car, etc.

AvGas is not legal for road use because it has no road gas tax assessed on it and because it is leaded. Penalties may exist in certain states or counties for airports selling it to non-flyers, but there is no nationwide blanket rule.

As for performance: what you were told is a steaming pile of sh_t. I've been using AvGas for 10 years in my dirtbikes, chainsaws, lawn mower, etc and it works perfectly. Easier starting, quicker revving, and never going bad. If it hasn't effed anything up in 10 years then then I'm guessing it's just fine.

As for mixing JetA and AvGas: it won't hurt a gas engine cuz it wouldn't run on it. It'd probably run in a diesel engine for a while before it smoked the fuel pumps. I'd guess it'd be pretty dangerous to run in kerosene heaters.

 

[MasterMech]

For those looking for an ethanol-free, high-octane fuel that can be stored longer than pump gas, check out automotive race fuel. It's available in every flavor under the sun including unleaded. VP Racing Fuels has a special small engine blend now but I'm sure it's expensive.

http://www.vpracingfuels.com/sef-94.html

I can speak for the quality of VP Fuels from motorcycle racing, as long as you want to put $30-$50/gallon into your chainsaw. I found such fuel only made a detectable difference in a high-compression engine running at very high cylinder temps, and even that was often only measurable on a dynamometer. VP's unleaded product is also oxygenated, meaning relatively short shelf life. IMHO, waste of money in a production engine of any type.

Are we really having this conversation about chainsaws?

OTOH, there is NO smell in the world like the smell of a 2-stroke burning race gas on a cool fall morning. No, not even... that.

VP Racing's SEF94 is $128 for 16 1 qt containers so that makes it $32 a gallon plus shipping. I'm never griping about $4 a gallon again. :lol: I remember buying race fuel (don't remember the brand/blend) for about $8 a gallon a few years ago.

 

[bluedogz]

Additionally, there are many different types of "avgas"... what the rookie racers tended to show up with was "blue gas", LL100, dyed the same way ag diesel is. It's just pump gas @ 100 octane. Useful at high compression, but little reason it would start better or rev quicker or anything else. I'm puzzled by Bigg_Redd's experience, but I'm not a chemical engineer. I guess if you're running a motorcycle at average revs over 7000 and 12:1 compression, it'd help...

 

[Bigg_Redd]

Additionally, there are many different types of "avgas"... what the rookie racers tended to show up with was "blue gas", LL100, dyed the same way ag diesel is. It's just pump gas @ 100 octane. Useful at high compression, but little reason it would start better or rev quicker or anything else. I'm puzzled by Bigg_Redd's experience, but I'm not a chemical engineer. I guess if you're running a motorcycle at average revs over 7000 and 12:1 compression, it'd help...

It is superior in 2 stroke engines - motorcycle, chainsaw, weed eater and air cooled 4 strokes. Neither of which are high compression applications. In fact, I've never tried in in a high compression engine.

I'm no engineer either, but I do know "easier starting" and "quicker revving" and "never gums up a carb."

 

[jonwright]

Probably never gums up since it doesn't have ethanol in it.

Use any of the old VP U4? Gums the hell out of a carb if left in it (I think VP has gotten better about this - but still I would be cautious).

Run oxygenated fuel like U2 in your 2smoke your jetting will be way lean if you don't compensate (and thus - seize if you are lucky - detonate and totally trash your engine if not lucky).

Some local places do sell fuel with no ethanol that I ATTEMPT to frequent for my small engines. I can tell you for many of my smaller 4st engines - lawn mowers and my 4st motorcycles - after they've sat for a while with ethanol the float bowls need to be drained and fresh fuel put in if you want it to run worth a darn. And if you are unlucky (which I usually am) take the carb apart and clean out the jets.

As far as higher octane gas giving you HP in a bottle, that's not supported by many engine builders and articles. Higher octane works by slowing down the burn in higher compression engines thus keeping detonation under control. Given the same engine lower octane fuel actually gives you a bit more power. But you need a Dyno to show it.

"quicker reving" and likes that Red has seen are attributes that are rather subjective - like taking the muffler off your bike and saying it's faster. It really isn't - it's just louder.

I know red necks that SWEAR by taking the muffler off their motorcycles. All they are really accomplishing is making more noise, losing low end torque, and irritating folks with noise.

Personally I don't see the point in AvGas - and I certainly don't buy that it gives any more power.

 

[MasterMech]

Probably never gums up since it doesn't have ethanol in it.

Use any of the old VP U4? Gums the hell out of a carb if left in it (I think VP has gotten better about this - but still I would be cautious).

Run oxygenated fuel like U2 in your 2smoke your jetting will be way lean if you don't compensate (and thus - seize if you are lucky - detonate and totally trash your engine if not lucky).

Some local places do sell fuel with no ethanol that I ATTEMPT to frequent for my small engines. I can tell you for many of my smaller 4st engines - lawn mowers and my 4st motorcycles - after they've sat for a while with ethanol the float bowls need to be drained and fresh fuel put in if you want it to run worth a darn. And if you are unlucky (which I usually am) take the carb apart and clean out the jets.

As far as higher octane gas giving you HP in a bottle, that's not supported by many engine builders and articles. Higher octane works by slowing down the burn in higher compression engines thus keeping detonation under control. Given the same engine lower octane fuel actually gives you a bit more power. But you need a Dyno to show it.

"quicker reving" and likes that Red has seen are attributes that are rather subjective - like taking the muffler off your bike and saying it's faster. It really isn't - it's just louder.

I know red necks that SWEAR by taking the muffler off their motorcycles. All they are really accomplishing is making more noise, losing low end torque, and irritating folks with noise.

Personally I don't see the point in AvGas - and I certainly don't buy that it gives any more power.

Ethanol itself doesn't gum up carbs. Rather the opposite since alcohol is a solvent. It does absorb moisture/condensation tho and corrode the insides of metal tanks and carburetors after it "phase separates" and certain rubbers and plastics will degrade over time if exposed to it.

I whole-heartedly agree with the rest of your post! ;-)

 

[woodchip]

My Dad used to be in the RAF and he sometimes used Avgas in his motorcycle.

He eventually had to get new valves as it burned out the valves and seatings.

Mind you, this was during the Berlin Airlift when he worked as a fitter on C47's, things have changed a little since then ;-)

 

[jonwright]

Probably never gums up since it doesn't have ethanol in it.

Use any of the old VP U4? Gums the hell out of a carb if left in it (I think VP has gotten better about this - but still I would be cautious).

Run oxygenated fuel like U2 in your 2smoke your jetting will be way lean if you don't compensate (and thus - seize if you are lucky - detonate and totally trash your engine if not lucky).

Some local places do sell fuel with no ethanol that I ATTEMPT to frequent for my small engines. I can tell you for many of my smaller 4st engines - lawn mowers and my 4st motorcycles - after they've sat for a while with ethanol the float bowls need to be drained and fresh fuel put in if you want it to run worth a darn. And if you are unlucky (which I usually am) take the carb apart and clean out the jets.

As far as higher octane gas giving you HP in a bottle, that's not supported by many engine builders and articles. Higher octane works by slowing down the burn in higher compression engines thus keeping detonation under control. Given the same engine lower octane fuel actually gives you a bit more power. But you need a Dyno to show it.

"quicker reving" and likes that Red has seen are attributes that are rather subjective - like taking the muffler off your bike and saying it's faster. It really isn't - it's just louder.

I know red necks that SWEAR by taking the muffler off their motorcycles. All they are really accomplishing is making more noise, losing low end torque, and irritating folks with noise.

Personally I don't see the point in AvGas - and I certainly don't buy that it gives any more power.

Ethanol itself doesn't gum up carbs. Rather the opposite since alcohol is a solvent. It does absorb moisture/condensation tho and corrode the insides of metal tanks and carburetors after it "phase separates" and certain rubbers and plastics will degrade over time if exposed to it.

I whole-heartedly agree with the rest of your post! ;-)

Ah...yes, yes. Taking a bit of shorthand there. I thought that because alcohol does NOT absorb water it allows the water to separate in the fuel....rather than being absorbed and part of the solution.

 

[wkpoor]

I think this has been brought up in the past . . . but thought I would bring it up again . . . just because I recently was told by some folks working at a local airport that there is a pretty large fine for them if they are caught selling av gas to anyone that doesn't have an aircraft with a tail number . . . not sure if this is just at this airport or all over, but I found it interesting.

Moreover, when I asked a mechanic friend (also a former stock car driver) he confessed that he has used some av gas in his stock car . . . but said the combination of the leaded gas and higher octane would tend to cause the engine to run a bit higher . . . or maybe it was just the octane would cause it to run hotter . . . he personally recommended not running it in any small engines . . . or even putting it in a vehicle.

Thoughts?

---

On a related note . . . these same folks at the airport dropped off two jugs at our training facility yesterday with a 50-50 mix of av gas and Jet Fuel A for use in my training fires . . . however, it appears as though someone came along and saw the blue "Kerosene" jug and the red safety gas can and decided to use them.

Kinda sitting here wondering what will happen if they try to burn the mix in a kerosene heater or in their oil furnace . . . and what will happen if they try to burn the mix of gas in their snowmobile, ATV, car, etc.

I am an A&P and I really can't comment on the health side of the issue but to say if it is indeed that harmful then we should all be dead by now. You can really smell it taxing around, much more so than I have ever smelled it from my chainsaws and mowers. All ramp personal would be sick and after 25yr working at an FBO I no of no one that is ill or came down with something related to the lead in 100LL.
As for small engine use. The heat an engine makes is related to its compression more so than the fuel type. Aircraft engines are very low compression so the theory of high octane in low compression engines getting hot is pooy. As long as they make it I will use it!

 

[BrotherBart]

Glad to see that there is so much agreement on the subject. :lol:

I burn the stuff with corn liquor in it in everything and the only problem I have had is it swelling the fuel cap in the 1991 saw so bad I couldn't put it back on.

Of course I haven't pulled my generator up for a hover check lately. :coolsmirk:

 

[nate379]

Must be a local thing or just at that station. Can buy 100LL around here without trouble. It's fairly expensive though.

[quote author="firefighterjake" date="1320784413"]I think this has been brought up in the past . . . but thought I would bring it up again . . . just because I recently was told by some folks working at a local airport that there is a pretty large fine for them if they are caught selling av gas to anyone that doesn't have an aircraft with a tail number . . . not sure if this is just at this airport or all over, but I found it interesting.

 

[firefighterjake]

And an update . . . turns out my would-be "thiefs" was an Engine Company that happened to go out to the Training Facility in the time between when the fuel cans were dropped off and when I arrived for the class . . . saw the fuel cans and figured they would move them to the training building . . . of course they never thought to pass on the fact.

My faith in humanity is restored . . . but I am secretly a bit disappointed . . . I was hoping to hear about someone's oil furnace blowing up after they poured in a bunch of the stolen fuel.

 

[nate379]

gas will burn in an oil burner without trouble.

I wouldn't recommend it, but I may... or may not have... done it before. (long story, won't get into it)

 

[woodchip]

but I am secretly a bit disappointed . . . I was hoping to hear about someone's oil furnace blowing up after they poured in a bunch of the stolen fuel.

I can imagine you all waiting for a shout to race out to the fire, and get your empty cans back ;-)