WRK

My Feedback: (2)

According to the people at DA they say that they can tell of an engine has been run on Aviation gas because the piston and other parts show signs of corosion and the sparkplug looks like the engine was running hot.

I am having a hard time imagining this as this gas when used in aircraft engines surley does not cause this to happen in those engines and their internal parts are aluminum too as far as the pistons and cylinders.

keith at BME says aviation gas causes his engines to run hotter but the caloric value of aviation gas is about hte same as other gasolines, wonder if you know anyone who has run into problems running aviation gas?

flierbk

Warren

My Feedback: (72)

I'd be most concerned with the amount of lead in aviation gasoline. Even the 100LL is comparably higher in lead content than the old automobile regular gasoline.

Tired Old Man

My Feedback: (1)

Higher octane ratings and increased lead levels are present in avgas. I don't know if they will harm a model engine or not, but the dye present in avgas will give it away in a heartbeat. If you've been using it, an inspection will show it.

Dan767

My Feedback: (19)

The spark plug will look much lighter in color, instead of the tan color it should have. Avgas also has inhibitors to keep the gas from vaporizing more at altitude. This lessens the chance of vapor lock.

JohnVH

My Feedback: (38)

Dont see why anyone would waste their money on it... the engine doesnt need it, and pump gas is pretty cheap and easier to get.

Diablo-RCU

My Feedback: (1)

Avgas has a few advantages over pump auto gas. It doesn't smell and it doesn't decompose and turn to varnish as quickly during prolonged storage.

tkg

My Feedback: (1)

For what Av cost, you could throw away your "plane" gas (put it in your car gas tank) each week and have fresh gas next time and still be cheaper than burning AV gas.
AV gas DOES smell MUCH less and for some people thats important. And yes its very easy to tell if an engine has been buring AV gas.

WRK

My Feedback: (2)

The question still remains as to what damage it could do to R/C our engines and why DA and BME don't like it, I would like to know how it hurts our engines as DA claims but does not hurt full scale aircraft engines. It would not change performance signifigantly and I don't see how it can cause engine damage to two stroke engines.

It stores much better, does not smell nearly as bad and does not form varnish like auto gas can do, it also is cleaner fuel as far as unwanted water etc. Some claim it does not produce as much power but I doubt it makes enough difference to notice.

Tired Old Man

My Feedback: (1)

Bottom line is the manufacturer sets the specs for the warranty. If they say don't do it and you do it anyway, say bye-bye warranty. Since it's already your engine, do what you want with it, but recognize that you may not have a warranty if and when it's needed.

tkg

My Feedback: (1)

It makes most model engines run hotter, this is where the damage comes from.
Full size aircraft engines are DESIGNED to run on this fuel and 99% of them are 4 cycle engines.
SO you makes your choice and pays your money.

WRK

My Feedback: (2)

I wonder why it makes the model engines run hotter it has no more caloric value?

JohnVH

My Feedback: (38)

maybe has something to do with it burning slower as well?

Diablo-RCU

My Feedback: (1)

Here's some info on avgas vs racing auto gas. They point out that the needles need to be richened for avgas because of the lower fuel density. If you don't adjust the carb richer, the engine will run hotter for sure.

Racing Gasoline Verses Aviation Gasoline
written by, and thanks to
Tim Wusz
76 Products Company

I am going to attempt to address the controversy of aviation gasoline verses racing gasoline for use in race cars. Some racers use aviation gasoline which is fine for some applications but does have shortcomings. There are several grades of aviation gasoline (avgas) that we must identify before going any farther.

1. Avgas 80/87: this product is used in low compression ratio aircraft engines, contains little or no lead, is red in color, and should not be used in any automotive engine due to a low motor octane number of about 80.

2. Avgas 100/130: this product that can be used in some automotive engines. It has both research and motor octane numbers slightly over 100. Avgas 100/130 is green in color, contains four grams of lead per gallon, and is becoming harder to find.

3. Avgas 100 LL: the LL stands for "low-lead" which means two grams per gallon, low compared to the avgas 100/130 that it was designed to replace. It has research and motor octane numbers very similar to the 100/130 product previously discussed. The color is blue. This product sometimes has a high level of aromatics which can contribute to lazy throttle response and dissatisfaction of the consumer.

4. Avgas 115/145: this product was developed for high performance piston aircraft engines used in world war II and in the Korean war. It is very hard to find anymore due to lack of demand although it is of very high octane quality. The color is purple.


The remainder of this discussion will assume that our basis for comparison with racing gasoline is avgas 100/130 and/or 100 LL since they are both available and have acceptable octane quality for limited applications. When the word "avgas" is used, it will refer to avgas 100/130 or 100 LL.

Avgas is less dense than most racing gasolines. Instead of weighing about 6.1 to 6.3 pounds per gallon like racing gasoline, it weighs 5.8 to 5.9 pounds per gallon. The racer must compensate for this by changing to richer (larger) jets in the carburetor when changing from racing gasoline to avgas.

The other major difference is octane quality. Avgas is short on octane compared to most racing gasolines. Many racing engines with "quick" spark advance curves or with no centrifugal advance have more spark advance at low rpm than avgas and some racing gasolines can handle. The result is detonation, especially during caution periods in circle track racing because all of the spark advance is "in", rpm is low, and part throttle air fuel ratios are too lean for the operating conditions. If the driver does not "work" the throttle back and forth, pistons can be "burned" which melts away part of the aluminum piston material. Inadequate octane quality is one of the quickest ways to destroy an engine. Pistons can be severely damaged during one acceleration where detonation is present and the racer may not know what is happening until it is too late.

For maximum performance and power from a racing engine, racing gasoline will normally provide better performance than avgas. Avgas can be a good gasoline for some applications, but since most racers do not know the octane requirement of their engines, they would be better off with a "real" racing gasoline that will give them the overall resistance to detonation that they need to protect their investment. If someone has spent from $15,000 to $50,000 or more on their racing engine, it is foolish to cut corners on gasoline be sure you have a gasoline with adequate octane quality.

written: 11/16/95

JohnnyJ

My Feedback: (1)

I have run 100LL avgas in my ZDZ, Zenoah, Quadra, and Brison and have noticed no ill effects.
I have not measured any engine temps.
Perhaps someone will check the temps using decent probes and gauges(not a temp gun) for us.
Full size automobile engines are designed to run on pump gas(mogas) and 99.9% of them are 4 cycle engines.
I have run several full size airplane engines on avgas and mogas and have noticed no difference in the short term.
The aircraft have egt and cht instrumentation on board.
In the long term I have seen engine damage caused by mogas.
Mogas doesn't burn as clean as 100LL in full size aircraft and leaves deposits on the exhaust valve and puts more crap into the rest of the engine thru blow-by.
I've been twisting wrenches on and flying full size for over 30 years...haven't seen everything yet!
I use whatever fuel in my model engines that is easily available...usually 100LL because it smells much better than mogas and is easily available.
The weight of 1 US gallon of 100LL is 6.01 lbs@ 15 degrees Celsius as per FAA and Transport Canada approved info.

Good Luck
Happy New Year
John

mrbigg

My Feedback: (21)

turbo blue (103 octane) mixed with Bel-Ray MC-1 used to run well in my dirt bike (ported and polished CR500). this gas contains lead also. had a blueish tint to it. man did it smell good out the exhaust..............

JohnVH

My Feedback: (38)

I was actually going to get some avgas for my race car, cheaper than using 110leaded and I really dont quite need the 110.

Panzlflyer

My Feedback: (15)

The trouble is what we use are not "Aircraft " engines but very very close cousins of CHAINSAWS.
Comparing and aircraft engine to a chainsaw just doesnt work.

jongurley

My Feedback: (29)

My Uncle Drag Races and he is also a modeler as well as a full scale pilot, he uses AVgas from our private airport for everything except for automobiles,,, The gas is Blue in tint, last year they sent three samples off to the FAA labs for testing, they came back as 105 octane, 105 octane and 103 octane, he has ran AVGAS in everything, and as he states the AVGAS gives NO more power to anything except for his Drag Car (Because of MSD electronic ignition, cams etc,etc,) but it burns so much CLEANER in everything,,, that is why he uses it,

BBW Walt

My Feedback: (11)

The "Gas Cities" gas station chain sell a 100 octane Racing gas. Its a blue in color stuff with a more pleasant oder than regular gas. Myself and 3 others use this stuff in our planes at our field and did all this past season. It burns very clean, mixes very well and have had "0" issues with this stuff. I think there are a few advantages using this gas and the only disadvantage I have found is the $3.85 per gallon price. As long as I can get this stuff I will continue to use it. Happy New Year, walt

bofrcr

,,,Ok everybody,,,I'll throw in my 2 cents worth!!,,,LOL,,,I have been flying avgas in my engines since the late 70's,,,before there was an IMAA,,,By the way,,I'm #120,, the main reasons,,,better fuel quality,,,longer lasting,,,(avgas will remain "fresh" for 3 years),,don't have to de-fuel after each flight,,, a full tank lasts longer,,,I can't honestly tell if there's more power,,,but the throttle response is much better,,,in other words,,the carbs we use on ALL our chain saw,,and chop saw type engines,,,(let's face it guy's,,,doesn't matter WHAT anybody say's,,,that's where they come from,,sure,,some machine special crankcases,,and that's good,,,but ask yourself,,,where do they get the jug and crank assembly's??) are either walbro or tilotson, and I've seen a few zama's,,,they where designed to hold the engine at idle,,,and transition to full power,,,no mid range,,,but we're fortunate that they do!!,,, you might hear of the term,,"flat spot",,refering to a point somewhere between idle and full power,,,on the control,,I've found out ,,with avgas,,it's greatly deminished,,,better linearity on the throttle stick,,, As when doing any fuel change,,,you reajust the needle valve. Yes you have to richen it.,,I have seen guy's that are scared to death to touch the needle valve!! I ALWAY'S make sure I can make ajustments,,, WHILE the engine is running in the SAME configuration as it will fly!!,,,meaning with the cowl and spinner on,,,it DOES make a difference!!,,,Car gas is junk.,,,Plain and simple.,,,Stop and think about it,,,modern day cars all have computer controled engines that constantly are ajusting the mixture through the fuel injection,,,sensors for exhaust,,,pvc valves,,electronic igntion ajustments (timing),,they can run trash and you'd never know!! It's said that car gas is supposed to last a month??,,,my expereince say's 3 weeks,,,if your lucky!! Here in Ohio,,we don't have a fuel quality standard,,,I won't pursue that,,,,anyway,,,I'll stop rambling,,,it's just my opinion,,,