J.P. Instruments EDM 740 Pilots Guide - Manual (Page 31)

For Your Safe Flight Page 31
Common Misapplications
Some of the more common misapplications made by first-time EDM
users are presented here in an attempt to help you avoid similar
problems.
Problem Situation Corrective action
Failure to pre-lean before
performing LeanFind or
you stopped leaning.  Follow the pre-lean
procedure in ‘LeanFind
Mode’ section (pg 22).
LeanFind finds a
‘peak’ too soon.
Leaning too slowly.  Lean more quickly.
Peak not found Lean Find not activated or
you stopped leaning.  Lean at the speed of
approximately 10°F per
second.
Off-scale EGT bars,
too high or low You forgot that you set the
EDM in the Normalize
view and later notice that
the EGT bars go off-scale.  The higher sensitivity
(10° per segment) of
the Normalize view can
quickly go too high or
low off-scale with only
small changes in EGT.
First cylinder to
peak is not the
hottest This is normal. The first
cylinder to peak is not
necessarily the hottest.  None
EGT rises during
single magneto
check This is normal, due to
incomplete combustion
persisting longer.  None
EGT not uniform
during low power
operation This is normal. Fuel and
air distribution is not
optimal at low power
settings.  None
No display of %HP FF, MAP, RPM, OAT not
reading or not equipped  FF, RPM, OAT, MAP
required for %HP