J.P. Instruments EDM 960 Twin Pilots Guide - Manual (Page 28)

For Your Safe Flight Page 23
LeanFind Procedure—General Explanation
Lycoming and Continental have established specific restrictions on
leaning that must be followed, such as percent power, climb leaning,
and TIT limits. Lycoming recommends operation at peak EGT at
75% or less power only. Continental recommends operation at peak
EGT at 65% or less power only. This guide does not supersede
specific recommendations of the engine or airframe manufacturer. It
is your responsibility to know your aircraft’s limitations.
Pre-leaning: The leaning process typically begins with ‘pre-leaning’ to
insure all
Lean Find-Initiation: Initiate the EDM leaning mode by tapping the
LF button. Note that the EDM displays its current leaning mode
momentarily: ‘ROP’ for operating Rich of Peak or ‘LOP’ for operating
Lean of Peak. To change, simply hold STEP and LF until the display
shows the other mode. The EDM is now waiting for a 15° rise on any
EGT (this feature significantly reduces false peaks). Lean the mixture
without pausing to achieve about a 10 deg per second change. With a
vernier mixture control, turn the knob about a quarter turn every second.
With a non-vernier or quadrant mixture control, lean slowly and
smoothly about 1/16 inch every five seconds (note: leaning accurately
with a quadrant system is difficult due to its mechanical linkage).
cylinders are operating rich of peak EGT (note: you can
optionally activate ‘Normalize’ - hold LF until NRM appears - making it
easier to confirm all EGT’s decrease). Now enrichen the mixture to
achieve a 50° drop on the hottest EGT. Insure that all EGT’s decrease.
Wait one minute to allow temperatures to stabilize.
Lean Find-Activation: When a 15° EGT rise occurs, LeanFind
activates (indicated by a cylinder I.D. box flashing over the number of
the hottest EGT). Remember: The LeanFind mode is not active until a
cylinder I.D. box is flashing. To show the progress of the leaning
process, the EDM now displays the hottest EGT in the left side of the
digital display and the fuel flow in the right side. This information allows
you to observe the EGT behavior throughout the leaning process.