May be a bit "advanced" but there's a whole science to this. The two + day course was a killer, but I learned much. One thing I will say is that i applies to all engines, weedeater through 3 row radial.
http://www.advancedpilot.com/ ----- Original Message ----- From: Ed Burkhead To: 'Hartmut Beil' ; [email protected] Sent: Sunday, February 24, 2008 5:22 PM Subject: RE: [ercoupe-tech] Re: LEANING THE MIXTURE..the secret Hartmut wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> While I was playing around with the control, it came to my mind that it might not be emphasized enough that the mixture control on Stromberg works ONLY when you have throttled back a bit, like 3/4 th of the full range. The Stromberg will not show signs of leaning at full throttle or at idle. It is important to remember that. At full throttle, the leaning effect is maybe there but I can not feel any roughness, regardless how far I pull the control. At idle there is no effect either, since the throttle is closed and no low pressure can be used for creating the leaner mixture - the low pressure port of the leaning mechanism lies below the throttle flap. Ok this is hard to understand without seeing at least a diagram. To say it simple, Strombergs can only be leaned at a partial throttle setting and one should put that into consideration. <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Hartmut, I was certainly successful at leaning to find a peak rpm at full power at high altitude airports and when climbing. I never tried it on the ground near sea level or at full power and low altitude. I WAS using a sensitive EGT with 10° gradation marks. For that matter, I could barely find the rough point in flight by hearing/touch alone. By the time I was getting significant rpm drop, it was about ready to drop a lot. But, the EGT gauge gave me excellent control whenever I leaned whether it was at full power for a high altitude takeoff, full power during climb or in cruise. Following the information I could find, I used 50° degrees on the rich side of peak for cruise and 100° on the rich side of peak for high power. Anyone know better, more authoritatively recommended numbers? Ed
