rtn9105

My Feedback: (35)

I'm pretty new to gas engines and I was wondering if using 100LL avgas in my ZDZ 40 will hurt the engine?
I'm not trying to get more performance out of the engine, I would like to use the avgas because I have to transport my airplanes to the flying field inside my SUV and the avgas doesn't have the bad smell that you get from the pump gas, if you get any on your hands as soon as it's evaporated the smell is gone from your skin, and it doesn't go bad if you leave it sit in the can for a few weeks. I know the manufacture only recommends pump gas but does anyone know if the avgas will hurt the engine?

brad59

My Feedback: (32)

100 low lead actually has a lot of lead in it so it should help with internal lubrication. It is also much more stable than mogas so would be good for those of us who keep a can in the garage for six months. The increased octane will not help our engines unless you increase the compression ratio or increase the pressure of the fuel/air charge by supercharging. Avgas is around 50% toluene which is what they make plastic model airplane glue from. It may smell better but will give you a great headache if you get exposed for to long so beware.

3dbob37n

Understand that the higher the octane, the lower the burn rate. The leads slows down the burn rate and prevents knocking which can destroy a full scale aircraft engine.
In one sense, higher octane is less powerful that low octane. At least in the sense that it does not burn as quickly as low octane.
With your lower compression engine, I imagine all you would get is less power and fouled plugs.
It might be worth trying but watch your head temperature closely.


3dbob

bubbagates

My Feedback: (32)

Shoot Mike Dooley at RCShowcase an email and ask him. He is really good with these engines. [email protected]

If I had to venture a guess I would say no, the amount of heat generated by the higher octane rating may be a problem and the other thing I would wonedr about is will the oil break down.

The other thing is getting the avgas. If memory serves me I do believe you need to hold a private pilots license or recreational pilots license and possibly the medical to purchase it.

I'm probably stretching a bit here but....

Please post the answer when you get one.

Antique

My Feedback: (4)

I use 100L from my local airport, no problems..It might be up to the airport manager, ours likes RC airplanes and we can fly there any time..He even has some pictures of RC planes and pilots on his desk...[8D]
I use it because my wife won't let me in the house after running engines in the shop on auto fuel
My friend Ron buys it for his Buick V6 Grand National, makes it run really well

excaliber

yup,100LL mixed with Amsoil 100:1 works fine. Biggest problem is getting from an airport.

rtn9105

My Feedback: (35)

I don't have any problem getting the 100LL, I can get it from the local airport right out of their pump.
I did send Mike at RC Showcase an email, he said they only recommend pump grade gasoline and that there isn't any advantage to using the 100LL.

Zeeb

My Feedback: (41)

Having worked on a bunch of the airplanes that use 100LL, I might offer a few thoughts;

This fuel was brought out as an EPA approved low lead replacement for the 100/115 Octane "Green" gas that was run in high performance piston aircraft engines, usually turbocharged. It doesn't work well in those engines as it requires about a 15% increase in the fuel burn in order to maintain EGTs on those engines. It works even worse on normally aspirated engines which were originally designed to run 80/87 Octane "Red" gas which is no longer made either, with a bunch more sparkplug fowling, higher fuel flows, and less power. The two octane ratings indicated what could be expected in the "leaned out" or "full rich" mixture conditions since the mixture setting is controlled by the pilot.

I had an 1100cc Honda Interstate that I put some 100LL in one day at work since I'd run the thing clear out of fuel, I didn't make it the mile to the local service station before it was missing something horrible. When I got back to work and pulled the sparkplugs, I don't think I've ever seen that much lead on sparkplugs.

I can't say for the rest of the Country, but I would think that if you show up with an approved fuel container, you should be able to buy the stuff at any FBO (Fixed Base Operator) found at local airports. There were always individuals showing up with cans for worked over snowmobiles, ATVs, race cars, etc. It will also cost you quite a bit more than automotive fuel and if you run an analysis on it I think you'll find that it's really not suited for those applications either.

IF you are dead set on getting a higher octane fuel, you'd be better off just buying the octane booster, or around here there is one service station that sells high octane off road fuel that's about twice the price of the regular automotive 91 Octane stuff.

Of course the above is JMHO, YMMV...

iflyj3

My Feedback: (7)

FYI and from memory. When 100LL was introduced it contained 2.0 grams per gallon lead. The old 80/87 it was supposed to replace only had .5 grams per gallon. 80/87 avgas had about the same lead content as regular leaded car gas at that time. I had lead balls short out plugs when I ran 100LL in my plane, so I went to auto gas.

Have you tried Coleman stove fuel? I don't know if it smells or not. That is the fuel Maynard Hill uses for his record setting flights.

BBW Walt

My Feedback: (11)

If your looking to run HI octane fuel our Gas Cities Stations sell 100 octane racing gas. Its blue in color, costs $4.45 a gallon as of last Sunday, and works very well in everything I've put it in. I have not seen an airplane gas engine that didn't like it. We have several others that exclusively burn this stuff and the results have been the same. It has an indefinate shelf life, wont turn to varnish, smells and looks cool. I am on my 3rd season with this stuff mostly running a 3W-QS106, a DA-150, a DA-100, and a 3W-150, 3W-80 and an occasional G62. Contrary to whats always said about Higher octane, I believe this fuel burns slower and a slight bit cooler. I do not believe Im gaining any power with this stuff and I know for a fact I have not lost any power, but I like the other benefits and with one real big one, it burns very clean mixed with KL310 Klotz at 50-1...Additives in gas here change with the seasons due to temperate changes and this fuel is consistantly mixed exactly the same. Your results and opinion will probably vary but Im staying with it. My motors run awesome...Just come to Wheeler Indiana and ask

carlosponti

My Feedback: (1)

if its the smell that bothers you, you may be able to run Coleman Fuel(white gas). in weedeater engines it was used years ago because lead would foul plugs in two cycle engines. you wont get a performance boost or lacking of. it is 60 octane and doesnt smell. i never have used it but i have heard from others that do. and its like 5 bucks a gallon the last i remember.

rtn9105

My Feedback: (35)

No Glo, thanks for the info on the racing gas, I'll check and see if any of the local stations have it. I'm not really concerned with the higher octane it's just the smell inside my car.
carlosponti, I've considered the coleman white gas but ZDZ says not to use it either and I just don't want to hurt this engine

cygnet

My Feedback: (33)

I run 100LL in my DA100 I have put througt 25 gallons this year and it just keeps running better every time out. I also check my plugs and there is NO build up of lead. As for power I run stock mufflers and turn a 28x10 at 6600 RPM 3500ft. Just my .02

Ben Diss

My Feedback: (23)

Guys- If the gas you're getting from the pump is BLUE, it's avgas 100LL. Feds mandate that 100LL be dyed blue and that it is the only gas sold with that color. This helps prevent fueling errors in airplanes.

-Ben

carlosponti

My Feedback: (1)

another solution is from harbor freight there is a cargo carrier that goes on the trailer hitch.

http://www.harborfreight.com/cpi/cta...emnumber=34313

supports 500 pounds and you could strap your fuel to it and leave it on the outside of your vehicle.

if you want a different version there are acouple more down the list
http://www.harborfreight.com/cpi/cta...441&pricetype=

one in fact you just have to buy some wood to use as the top.

Zeeb

My Feedback: (41)

Ben is right on the fuel coloring...

I neglected to mention the fact that the 100LL was blue. It used to be there were three fuel grades and all were different colors to differentiate from each other. Red was the 80/87, Green was the 100/115, and Purple was 130/145 used primarily in the ex-military WWII fighters that you see around the Country.

There is a lot more to fuel composition than just how much lead it has, or what the octane rating is and engines are usually designed for a particular fuel based on that fuel's availability. ZDZ recommends high octane pump gas, or automotive fuel and that's what I run in my ZDZs. If you've found something you feel works for your application, then I'd say go for it but don't expect RC Showcase to be understanding about it if you have engine problems and want warranty work done...

BBW Walt

My Feedback: (11)

The racing gas that Gas Cities sells is blue in color and I'm quite positive it is not 100LL AV gas...

Tired Old Man

My Feedback: (1)

We run 100LL exclusively in our 100cc twins due to the lack of availability of other fuels. Our experience has shown increased plug fouling and reduced engine lives. The reduction in engine life could also be attributed to the fact that our engines usually run at a higher constant power output than most normal R/C engines. We typically maintain a 45 to 65% power output for up to 4 hours continuous. The plug fouling is pretty much a standard.

BBW Walt

My Feedback: (11)

I have been flying gas burners since 1986. I started out with a Quadra 35. All we used at that time was Lawnboy oil, continously. before Ashless because thats what Cliff Bennett said to run..I cant remember how many engines I have gone through, swapped, horse traded and destroyed but I have never fouled a plug in any of these engines. Once in a while I will pull one or two, have a look and see, wire brush the electrode, regap and go. I have burn't up a few modules and I usually put in a new set of plugs but with that exception that is it. My old oil injected motocross bikes, different story

RaceCity

Having logged more piston time than I care to admit, I can assure you that using 100LL in engines not specifically designed for it is a big waste of money.

"Octane" ratings aren't like nitro percentages. Contrary to popular belief, this fuel in and of itself does not boost the output of an engine. It does however permit certain engine designs to function properly, and it's pretty safe to assume that adaptations of yard tool engines aren't designed in this manner.

Unless the manufacturer of your motor specifically states that 100 octane, leaded fuels are to be used...save your money and buy regular, cheap-as-you-can-get pump gas at the local "Stop 'N Go". You'll burn less fuel, make more power and have more money in your pocket in the end.

'Race

RTK

My Feedback: (1)

The question I have is, where can you find approx. 87 octane gasoline that does not smell like this reformulated crap.

Tired Old Man

My Feedback: (1)

No Glo,

With all due respect, we run our engines in an enviornment and at continuous power levels that the average modeler would find unbelievable. Fouled plugs using 100LL and 50-1 Lawnboy Ashless are an absolute fact of life. The plug fouling situation is bad enough that we have developed a maintennance schedule that dictates we change and toss the plugs after every 10 hours of use. They are always near the point of failure at that point.

BBW Walt

My Feedback: (11)

I have no reason to doubt what you're saying but I've got to ask, What are you guys doing??? 10 hrs on plugs would be like 40-60 flights depending on your flight times.

RTK

My Feedback: (1)

They are flying UAV's in a very hot environment, pulling hard for many hours straight.

Just thought I would answer this one for you Pat.

Tired Old Man

My Feedback: (1)

Thanks Ralph.

10 flight hours is around 2 flights, +/-/