Well i've had a few good flights with my avistar for the past few weeks. Now i have started to get myself some gear of my own. I bought some fuel called Omega, 10%. I put it into the .40 la on the avistar and it flew rough. It would stall when inverted. And even shut off once in the air. After getting the fuel out. We put another guys 15% fuel into the plane and it flew great. This engine is suppose to be good for 10% also. What could cause this? Could it be bad fuel? Or a tuning Problem? Any suggestions appreciated.

Originally Posted by Xand

Well i've had a few good flights with my avistar for the past few weeks. Now i have started to get myself some gear of my own. I bought some fuel called Omega, 10%. I put it into the .40 la on the avistar and it flew rough. It would stall when inverted. And even shut off once in the air. After getting the fuel out. We put another guys 15% fuel into the plane and it flew great. This engine is suppose to be good for 10% also. What could cause this? Could it be bad fuel? Or a tuning Problem? Any suggestions appreciated.

HI,
i'M KINDA NEW LIKE YOU, BUT i'VE LEARNED WHEN YOU GET AN ENGINE RUNNING GOOD ON A CERTAIN TYPE AND PERCENTAGE OF NITRO, STAY WITH IT, CUZ EVERY TIME YOU CHANGE, YOU HAVE TO ADJUST THE MIXTURE. AND i THINK AN ENGINE SORTA GETS USED TO A DERTAIN FUEL. i RUN MY eVO .46 ON 15% AND IT LOVES IT.
sTAN

My .40la has only seen omega 10% and i have never had a problem with it, might be tuning.

Nitro can't be the be-all and end-all as many of us in NZ don't use any nitro. Engines still run OK. Guess it makes sense to retune if you change percentage, though.

Hi Wayne and Linv.
Ontario and New Zealand. Great! I'm from Florida, U.S.A. Maybe we all can get together and teach the world's people to get along. This is my answer to "why do I need to join a club?" Have a good day, you guys.
Stan

Adjust the carb for the fuel you're using. A 40LA will run fine on Omega 10% if adjusted properly.

Ivan

Hi

Suppose it could be bad fuel, try it on another engine.

more likely not though.

I just run mine on castor staright fuel mostly.

Simon

Our club gets a discount on 15% from the LHS, so we all run 15% in our LA's and don't have any problems. As someone mentioned, you tune your engine to the fuel you're running. There could be a difference in the type of glow plug that works best with one fuel over another, but I don't have enough experience to be able to know that for sure.

Stan

The person that was with me the day that i tried the fuel did some adjustments on it. He adjusted the screw with the spring on it from the carb and tried to tune it. I was running 15% in it before...and it ran perfect. He tinkered with my 10% omega for awhile and couldnt get it right. It wanted to act like it was starving for fuel. So we put 15% back in it and he tuned it perfectly in a matter of secs.

Will mixing fuels cause this kind of problem?

You may have either some bad fuel or a plug that can just handle 15% nitro but isn't quite hot enough for 10%. The fuel is the more likely thing though because a plug can usually handle a fair range of fuels before causing a problem. If a new plug (something like an OS 8) doesn't cure it then do what simhatus suggested and try the fuel in another engine.

My money would be on you needing to retune slightly for the new fuel or a different plug as stated. I use that fuel also, and no problems in an Evo .46 or a ST .40.

JG

Update...Well i went flying today, a guy had some Cool Power all synthetic fuel 10% also. We put a tank in my plane and tuned it alittle and it runs perfect. So the Casor/Synthetic 10% omega fuel is a bad bottle. We tried it several more times. I guess this is one of those rare things to watch out for. What can cause fuels to go bad? Could it be the heat from setting in the car? Could it even be the oil mixture? Anyway i bought me a bottle of the Cool Power fuel now so its all good.