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TO MUCH FUELL ON THE PLUGS 618

in 2 Stroke Technical Questions 13 years ago
Hello everyone, Bill I hope you are reading,
All my engine reading on my EIS panell are normal, A small discrepancy on Iddle between EGTs But goes away on middle and full throtle,
I notice to much fuell goes to the sparkplugs, and also notice I am using about 25% more fuell in flight,
I am afraid to start mesing up with the air screw again as I finaly am kind convinced that 1 turn on the one carb and 1 1/4 on the other one have gived me good results. What will be the item I need to check with to achieve the proper feed of fuell.
Any suggestion or advice will be appreciated.
Regards
Yanis

  • Re: TO MUCH FUELL ON THE PLUGS 618

    by » 13 years ago

    Yanis,

    What are your EGTs now. At idle, at midrange, and at full throttle?

    Bill.
      
    Report

  • Re: TO MUCH FUELL ON THE PLUGS 618

    by » 13 years ago

    Hi Bill amd thanks for the quick respond,
    On Idle I have about 50 degres diference, midle range a little less and full throttle about 20 to 30 degrees, Seems I am running to reach on all settings, from the 3 position on the needle inside the slide mine is set to the bottom one, I was thinking of moving it to #2 position, what do you think?
    Sparkblugs black and oily.
    Regards
    Yanis
      
    Report

  • Re: TO MUCH FUELL ON THE PLUGS 618

    by » 13 years ago

    Yanis,

    At full throttle your EGTs should be 1100f to 1150f. The bottom position on your needle clip is probably too rich unless you are operating at sea level in winter. I would move the clip up one notch and see what happens. This will not increase your EGTs at full throttle but will increase them in the midranges. There is an old saying about 2 cycle engines. They run best just before they melt.

    The higher you can SAFELY keep your EGTs in all ranges, the better horsepower and fuel efficiency you will have. My 182 usually runs around 950f to 1050f at cruise and 1150f at full throttle. Once you get the needle setting where you like it, about the only changes necessary are main jets. Top end EGTs will change with warmer and colder seasons. You may need to go with a larger main jet in winter and a smaller one in summer to keep your full throttle temps in range.

    You can adjust the idle air screw for smooth running at idle and it will not affect midrange or top end temps. the difference in idle temps between cylinders is not critical since you are never near the 1200f max.

    The newer jet needles have four clip positions instead of three and allow for much better tuning.

    Plugs should be a light brown color. White is too lean, black is too rich. Best time to look at the plugs is immediately after a flight. Even a well set up system will tend to have black plugs after a long idle period. They should never be wet or oily.

    Hope this helps,

    Bill.
      
    Report

  • Re: TO MUCH FUELL ON THE PLUGS 618

    by » 13 years ago

    Thank you Bill,
    One more question, If lock in the hand throtle to 2000 RPM which is where I realy want it when the engine starts and to stay IDLE, Then shut down the engine but live the trotle there at 2000rpm, Then turn in the large screw with the spring on it to the point that the slide rest on it will that give me a study 2000 rpm at starting with out making any other changes on the throttle cables? If so I think I should do that, because now I have to use the throttle and reach 2000 and idle on, If that works for the rpm setting then I will open the curbs and reset the neddle to #2 position and go from there.
    What do you think?
    Yanis
      
    Report

  • Re: TO MUCH FUELL ON THE PLUGS 618

    by » 13 years ago

    Yanis,

    That would work. After you do that, stop the engine and pull the throttle all the way back. You will probably have some extra play in the throttle cable. Check by lifting the cable housing up where it enters the cable adjustment screw on top of the carb. It should have about +/- one or two mm of free play. No more.

    Bill.
      
    Report
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