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fuel heating to prevent fuel icing. A fuel tem-
perature sensor monitors fuel temperature at
the pump and an oil bypass valve on the FHOC
will automatically operate to preclude exces-
sive heating of the fuel. If the fuel is too hot,
a white “L/R FUEL HEATER” advisory mes-
sage will be generated by the CAS (Figure 7-
23). If the fuel is too cold, an amber “L/R
FUEL HEATER” caution message will ap-
pear on the EICAS.
The bearings and gearbox areas are gravity
scavenged to the inlets of the five scavenge el-
ements in the oil pump, which returns the oil
through a common scavenge line to the oil tank.
All bearing, gearbox and oil tank areas are
interconnected by vent lines which connect to
a breather pressurization valve. The breather
pressurization valve provides an ambient vent
for the oil system at low altitudes and at high
altitudes increases the vent and tank pressure
to prevent oil foaming and to ensure proper oil
pump operation.
L E A R J E T 4 5
P I L O T T R A I N I N G M A N U A L
7-31
FOR TRAINING PURPOSES ONLY
FlightSafety
international
L OIL
PRESS
LOW
R OIL
PRESS
LOW
OIL SYSTEM WARNINGS ON CWP
ITT
L
F
1000
R
1750
LBS
FUEL
4450
50.0
49
60
984
50.0
80
60
1002
N2
OIL PSI
OIL
°
C
FF PPH
550
550
1700
OIL INDICATIONS ON EICAS
Figure 7-23. Oil System Indications
CAS Message
Logic Summary
Type
Msg
L R FUEL HEATER
L R OIL FILTER
L R ENGINE CHIP
Fuel/oil cooler failure, fuel too cold.
Engine oil filter impending bypass while on the ground
Metal particles in oil while on the ground
W = Warning
C = Caution
A = Advisory
L R FUEL HEATER
Fuel/oil cooler failure, fuel too hot.
L R OIL PRESS LOW
Low oil pressure, < 50 psi.
L R ENGINE CHIP
Metal particles in oil (inflight).
C
C
C
A
W
A
A
L R OIL FILTER
Engine oil filter impending by-pass (inflight).
CAS MESSAGE DATABASE