C172 Engine Question
03-21-2006, 06:18 PM
#2
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Originally Posted by BURflyer
What is the best way of adjusting the fuel/air mixture?
If your asking on how to best lean it, it all depends on what type of performance you want, best range or best endurance.
Anyway, the best place to find the most accurate/correct way to do it is in the Cessna 172 P.O.H. it should explain how to properly lean for both taxi and flight, and what you want the engine instruments to be reading for the type of performance you want.
03-21-2006, 08:41 PM
#5
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Originally Posted by BURflyer
What part of the poh explains that I can't seem to find it.
03-21-2006, 09:38 PM
#7
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The "best way" will also be determined by the aircraft having an Exhaust Gas Temp (EGT) guage. If you have one of these, you'll be able to lean much more precisely. If not, you're limited to using the old "lean until you get a rise in RPM and make it slightly rich from there" method.
Also, don't pull on the mixture, unscrew it. When it comes time to go full rich again, you can push in.
Normally, you'll lean after reaching cruise and setting cruise power. Now, if you're at a high altitude airport on a hot day (=high density altitude) it may be nesessary to lean for best power before taking off.
Also, don't pull on the mixture, unscrew it. When it comes time to go full rich again, you can push in.
Normally, you'll lean after reaching cruise and setting cruise power. Now, if you're at a high altitude airport on a hot day (=high density altitude) it may be nesessary to lean for best power before taking off.
Last edited by Pilotpip; 03-21-2006 at 09:40 PM.
03-21-2006, 11:13 PM
#8
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Since we are on the subject, isn't it true that with Carberuator equipped engines, using a EGT gauge to lean the mixture is much less accurate than fuel-injected engines since fuel injection systems distribute a much more precise and equal amount of fuel into each cylinder?
Therfor, some cylinders could be hotter than others in a carberuater equipped engine... Sorry its late
Therfor, some cylinders could be hotter than others in a carberuater equipped engine... Sorry its late
03-22-2006, 05:46 AM
#9
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Originally Posted by BURflyer
Thanks Alex, now my question is it recommended to lean at full power settings? Or do I have to reach my cruising altitude before leaning the mixture? How do you guys do it?
But remember, anytime you make a power change you should adjust the mixture, for the new power setting. The method I know (and this will help in complex aircraft) is if you are going to increase power, you rise from the right, meaning adjust mixture first, then prop (if you have it), then throttle, and you lower from the left if you aree decreasing power, adjusting throttle first.
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