Primary Lines
Scavenge Lines
From Oil Cooler
Propeller
Interface
Unit
Oil Supply to
Propeller
Oil Filler and
Dipstick
To Reduction Gear
Box
Chip
Detector
Internal Scavenge Pumps
To Oil Cooler
To Compressor and
Power Turbine
Bearings
Main Oil Filter
Pressure Pumps
External Scavenge
Pumps
EICAS
o
EXTENDED: 0 – 10 C
o
NORMAL: 10 – 105 C
CAUTION: 106 – 110 oC
WARNING: > 110 oC
WARNING: 0 – 40 psi
CAUTION: 40 – 90 psi
NORMAL: 90 – 120 psi
EXTENDED: 120 – 200 psi
WARNING: > 200 psi
T-6B Oil System Brief
 The T-6B contains an 18.5 quart capacity oil system that supplies filtered oil to Engine
Bearings, Reduction Gears, Accessory Drives, and the Propeller
 The Oil Tank is cast within the compressor air inlet and contains a pickup that is
designed to supply oil during both normal and aerobatic phases of flight
 Pressure Pumps to Oil Filter
 Contains a filter bypass in the event the oil filter becomes clogged
 Oil Filter to Oil Pressure and Oil Temperature Transducers
 Data is sent to the Engine Data Manager (EDM) first and then Oil Pressure data is sent
through the Signal Conditioning Unit (SCU)
 The SCU provides logic as to when to display the appropriate EICAS cautions and
warnings
PCL Setting
IDLE
IDLE
Oil Pressure (psi)
15 to 40
15 to 40
Time Duration
None
5 seconds
Caution/Warning
Amber Caution
Red Warning +
Amber Caution
IDLE
< 15
None
Red Warning
Above IDLE
40 to 90
10 seconds
Amber Caution
Above IDLE
< 40
None
Red Warning
*If Red and Amber messages illuminate while Oil Pressure indicates normal, this is
the result of an SCU failure
 To Compressor and Power Turbine Bearings
 Oil passes through various oil strainers in order to ensure clean oil is delivered to
components
 To Reduction Gears and Gearbox Assembly
 The Reduction Gearbox contains a Chip Detector, which detects ferrous material within the
oil and triggers the red CHIP warning on the EICAS display
 Propeller Interface Unit (PIU)
 The PIU coordinates with the Power Management Unit (PMU) in order to deliver the proper
supply of oil to the propeller system in order to control the propeller blade angle
 Scavenge System
 The scavenge system removes the oil from the components and routes it to the oil cooler on

the underside of the engine cowling
The scavenge system contains pumps inside and outside of the accessory gearbox
 Scavenge System to Oil Cooler to Oil Tank

Oil must be serviced within 30 minutes of engine shutdown. The best time to service the oil
is within 15 to 20 minutes after shutdown.
Applicable EICAS Indications:
OIL PX warning: Oil pressure at or below 15 psi, or oil pressure 15 to 40 psi for 5 seconds at idle;
Oil pressure at or below 40 psi above idle
CHIP warning: Engine chip detector indicates oil contamination
OIL PX caution: Oil pressure 15 to 40 psi at idle; Oil pressure 40 to 90 psi for 10 seconds above idle
Applicable Emergency Procedures:
Chip Detector Warning
Illumination of the CHIP warning indicates possible metal contamination in the engine oil supply. If the
contamination is severe, the engine may fail with little or no further warning. When the CHIP warning
illuminates, accomplish the following:
* 1. PCL - Minimum necessary to intercept ELP; avoid unnecessary PCL movements
CAUTION

Higher power settings may aggravate the existing condition.
* 2. PEL – Execute
Oil System Malfunction or Low Oil Pressure
NOTE




Use this procedure for any of the following: red OIL PX warning illuminated, amber OIL PX
caution illuminated, oil pressure fluctuations, or oil temperature out of limits.
If OIL PX warning illuminates and oil pressure indicates <5 psi, check OIL TRX circuit breaker
on the battery bus circuit breaker panel (left front console). If the circuit breaker is open, it may
be reset.
Due to the sensitivity of the signal conditioning unit, a single, momentary illumination of the
amber OIL PX caution while maneuvering is possible but may not indicate a malfunction.
Illumination of both red and amber OIL PX message while the oil pressure gage indicates normal
pressure indicates an SCU failure.
IF ONLY AMBER OIL PX CAUTION ILLUMINATES:
* 1. Terminate maneuver
* 2. Check oil pressure; if oil pressure is normal, continue operations
IF RED OIL PX WARNING ILLUMINATES AND/OR AMBER OIL PX CAUTION REMAINS
ILLUMINATED FOR 5 SECONDS:
* 3. PCL - Minimum necessary to intercept ELP; avoid unnecessary PCL movements
CAUTION

Higher power settings may aggravate the existing condition.
* 4. PEL - Execute