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.65LA preset for airbleed

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Old 06-27-2011, 07:05 AM
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dredhea
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Default .65LA preset for airbleed

Our youth flying program recently had a plane donated that was equiped with an OS .65LA. We don't know the history of the engine, but it seems quite new (good compression, turns smoothly), but we haven't been able to get it to run smoothly. It seems to be running very rich on the low end (lots of smoke, loads up) even though our engine "guru" opened the airbleed fully. I am taking the carb apart today and cleaning it completely to preclude blockage, but I need to know where to preset the bleed screw when I reassemble it. I'm anxious for an answer as we intend to pass this plane to a very deserving student ASAP. Thanks in advance for any assistance.
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Old 06-27-2011, 12:51 PM
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Default RE: .65LA preset for airbleed

The starting point for an airbleed screw is to set it so that it blocks 1/2 of the airbleed hole.

You get the high-speed needle set first at full throttle, then work on the idle speed and mixture. Too often, people try to get too low an idle RPM, which causes a multitude of problems. Anything under 2,500 RPM is good.
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Old 06-30-2011, 06:16 AM
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Default RE: .65LA preset for airbleed

Thank you for the info. I hope to get this engine tuned and running smoothly today
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Old 06-30-2011, 12:58 PM
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Default RE: .65LA preset for airbleed

Bax,
Thanks again for the info. I reassembled the carb, got the engine running and after setting the HSN, it took only 1/2 turn to get the mixture set. That engine screams on the top end and the idle is smooth as silk. I now have no problem giving it to a new young pilot. Your assistance made that possible.
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