TM 1-1520-238-T-4
6–136
Change 1
6–63.
OIL HOT NOSE GRBX 1 INDICATOR – IS LIGHTED WHEN HOD DISPLAYS HIGH NGB 1
6–63
OIL TEMPERATURE
Tools:
Nomenclature
Part Number
Tool Kit, Electrical
SC518099CLA06
Repairer’s
Tool Kit, Powertrain
SC518099CLA013
Repairer’s
Multimeter, Digital
AN/PSM-45
Personnel Required:
68D
Aircraft Powertrain Repairer/NDI
68X
Armament/Electrical Systems Repairer
152FG
Maintenance Test Pilot
References:
TM 1-1520-238-T-6
TM 1-1520-238-23
TM 1-1520-238-CL
Equipment Conditions:
Ref
Condition
TM 1-1520-238-23
Access provisions –
L200 access panel
and LN6 fairing open
WARNING
Turn off power before detaching or
attaching wires and connectors. High
current 28 VDC or 115 VAC is present.
Failure to do so could result in death or
serious injury.
1. Check HOD display for NGB 1 oil pressure
reading.
Is oil reading 28 LB or lower?
YES
Go to paragraph 6–62 to
troubleshoot OIL HOT NOSE
GRBX 1 indicator.
NO
Go to step 2.
2. Check pilot caution/warning panel OIL PSI
NOSE GRBX 1 indicator.
Is indicator lighted?
YES
Go to paragraph 6–60.1 to
troubleshoot HOD NGB 1
display.
NO
Go to step 3.
3. Check HOD display for NGB 1 oil temperature
reading.
Is oil temperature 121 C or higher?
YES
Go to step 6.
NO
Go to step 4.
4. Detach P18.
Does indicator remain lighted?
YES
Refer to TM 1-1520-238-T-6 to
troubleshoot the pilot
caution/warning system.
NO
Go to step 5.
5. Check for short between J61–A and P18–52.
Does short exist?
YES
Repair shorted wire.
Go to paragraph 6–13.
NO
Replace NGB 1 metallic chip
detector (TM 1-1520-238-23).
6. Inspect NGB 1 for cooling fin blockage
(TM 1-1520-238-23).
Is there blockage?
YES
Clear fin blockage and correct
damage (TM 1-1520-238-23).
NO
Go to step 7.
7. Check NGB 1 flexible coupling shaft and fan
(TM 1-1520-238-23).
Is fan blocked or damaged?
YES
Clear fan blockage and correct
damage (TM 1-1520-238-23).
NO
Replace NGB 1 lube pump
(TM 1-1520-238-23).
END OF TASK
