J.P. Instruments EDM 760 Pilots Guide User Manual
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limit the leaning process. TIT red line is generally 1650°F, and up to
1750°F in some installations. If during leaning the TIT exceeds red line by
less than 100°, the LeanFind procedure will continue to operate and the
TIT redline alarm will be suppressed for one minute, allowing you to
complete the leaning process. Otherwise the digital display will show, for
example,
I650 TIT and TIT will flash. You will notice that in some
cases the TIT reads 100°F hotter than the hottest EGT. This is caused by
unburned fuel in the exhaust igniting at the turbine inlet.
The reduced size of the
JPI Hastaloy-X-tip probes produces faster
response and more accurate than the massive factory installed probe.
Therefore
JPI probes may read as much as 100°F higher than the factory
installed probe. However, note that the engines were certified with the
factory installed probe and gauge, and this gauge reading is the limiting
factor when adjusting your engines.
Never exceed red line on the factory installed instruments.
Operation for each Phase of Flight
Engine Run-Up (you can add this to your run-up
checklist.)
Suggested setup:
•
Set engine to runup RPM
•
Normalize view
•
Manual mode
Verify:
•
uniform rise of about 50°F in all EGTs in single magneto
operation.
•
uniform rise of EGTs with application of the mixture control.
Be alert for:
•
unusually low voltage (less than nominal battery voltage)
•
cold OIL and normal oil pressure
•
abnormally high CHT
•
large drop in EGT on one cylinder in single magneto operation—
may be fouled spark plug.
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Engine Data Management