Oil System Flashcards
Normal oil pressure range above 72% NG is ___
90-135 PSI (green range)
Decrease in oil pressure below 90 PSI may indicate what?
Opening of the filter bypass as a result of a blocked oil filter
What is the minimum oil pressure with a power setting below 36 TRQ PSI (normal oil temp)?
85 PSI.
What is the maximum power setting at Oil Pressure 60 – 90 PSI?
23.9 TRQ PSI
What should you do if Oil Pressure falls below 60 PSI?
Land ASAP
What is the total oil system capacity?
3.6 US GAL / 13.6 litres
What is the optimal oil temperature?
74 to 80 degrees. (or just 80, as that is the middle of the green on the LCD)
What is normal oil temperature?
55 to 105 degrees (green arc).
What is the minimum oil temperature for engine start?
-40 degrees.
What is the minimum required oil temperature for takeoff?
10 degrees.
What oil temperature range is allowed for no longer than 10 min?
105 degrees to 110 degrees.
If the Oil is low, when will the Oil Qty CAWS come on?
60 seconds after shut down OR 60 seconds after turning on battery.
Upper Oil Pressure transient range:
135 PSI to 200 PSI for 20 seconds.
Lower Oil Pressure transient range:
40 PSI to 60 PSI for 20 seconds.
What is MAX HOT and MAX COLD refer to regarding shot down time?
Max hot = within 30mins of shutdown
Max cold = 12hrs after shutdown
What is the engine pressure system ran off?
The accessory gearbox.
What could be a possible reason you are observing a drop in oil pressure?
Oil filter has become all or partially blocked, and it has now opened the oil by-pass valve.
NOTE: a check valve will permit 15 PSI of oil pressure through the oil filter
What is the path of the oil system?
- Oil tank screen
- Oil pump
- Pressure regulating valve (90-135)
- Pressure relief valve
- Oil filter (bypass valve)
- Engine accessories
- Scavenge pumps (gravity fed from engine accessories)
- Oil strainer
- Fuel exchanger (oil-to-fuel heat exchanger)
- Back to tank
