For Your Safe Flight
Page | 25
Lean of Peak
leaning is as simple as:
A. Pre-lean your mixture.
B. Tap the
LF
button (verify
LOP
appears).
C. Lean mixture until
RICHEST
flashes
(
peak found).
D. Enrichen t
o the desired value ‘Lean Of Peak’.
L
Procedure
Scanner Example
(one engine)
Comments
1 Establish cruise
between 65 to 75%
power.
2 Pre-lean the mixture
to 50°F estimated rich
of peak on any EGT:
_________°F.
EGT
1490
CHT
370
* See ‘Pre-leaning’ page
23.
3 Wait one minute
Let engine stabilize.
4 Tap the LF button
LOP
Start Lean Find (if
ROP
appears, hold STEP & LF
until
LOP appears
)
5 Lean the mixture at
approx. 10°/second
without
pausing.
(cylinder I.D. box
flashes when a EGT
rises 15°F)
EGT
1520
FF
13.8
Flashing cylinder I.D. box
identifies the hottest EGT
and that an EGT has
increased at least 15°F
which arms the EDM to
now look for first EGT to
peak.
6 After the first EGT
peaks, you will see
LEANEST
for one
second and bars
coming from the top
down. Continue
leaning.
EGT
∆
-17
FF
12.4
When bars come from the
top down, the cylinder I.D.
box identifies the first EGT
that peaked (leanest).
Continue leaning.
7 When
RICHEST
appears, fine tune the
delta EGT to the
desired degrees
below ‘Peak’ (Lean of
peak).
EGT
∆
-45
FF
11.6
Lean of
Peak
target
leaner
richer
‘FF’
EG
T
0
-4
0
-8
0
Peak
8 If you hold PEAK, the
peak EGT recorded
will be displayed
along with FF spread.
EGT
↑
1560
FF
∆
0.6
Captured peak EGT value
and the FF spread
between richest and
leanest cylinders.