Lubrication Systems

Question 1

1. What is straight mineral oil?

Answer 1

Natural lubricating oil with no additives

Question 2

2. What is Ashless dispersant oil?

Answer 2

Mineral oil with additives that evening space contaminates throughout oil

Question 3

3. What is synthetic oil?

Answer 3

Man made by chemically altering the oil to achieve desired characteristics

Question 4

4. What is meant by multi viscosity oil?

Answer 4

Has a varying viscosity 5w30 (5 when cold 30 when hot)

Question 5

5. What are the purposes of reciprocating engine oil?

Answer 5

Cleans
Cools
Cushions
Seals
Lubricates

Question 6

6. What is the most important property that aircraft reciprocating engine oil must possess?

Answer 6

Viscosity

Question 7

7. What factors must be considered in determining the proper grade of oil to use in a specific engine?

Answer 7

Operating load
Rotational speeds
Operating temperatures

Question 8

8. What is the purpose of the oil flow control valve “oil cooler bypass vale”?

Answer 8

When oil is cool bypasses cooler
When oil is hot it goes to cooler

Question 9

9. What are some oil contaminants?

Answer 9

Gasoline
Moisture
Acid
Dirt
Carbon
Metallic particles

Question 10

10. From what location on a reciprocating engine is the oil temperature usually taken?

Answer 10

Wet sump - after oil cooler
Dry sump - anywhere between oil tank & engine

Question 11

11. What do metallic particles on an oil screen indicate?

Answer 11

Internal failure

Question 12

12. What could cause oil foaming?

Answer 12

Diluted oil
Contaminated oil
Oil level too hight

Question 13

13. What would be an indication of blocked oil cooler passages?

Answer 13

High oil temp

Question 14

14. What would be an indication of an inadequate oil supply?

Answer 14

Low oil pressure & high oil temp

Question 15

15. What type of oil is used in turbine engine lubrication systems?

Answer 15

Synthetic oil

Question 16

16. Where can you find the specified grad oil for particular aircraft?

Answer 16

Airplane Flight manual or the POH

Question 17

17. What are two types of oil coolers in turbine engine lubrication systems?

Answer 17

Air cooled & fuel cooled

Question 18

18. What is the meaning of oil flash point? Fire Point?

Answer 18

Flash point - gives off inflatable vapors
Fire point - will ignite

Question 19

19. What is the weight of aircraft engine oil?

Answer 19

7.5 lbs per us gallon

Question 20

20. What is the purpose of an oil dilution system?

Answer 20

Thins oil for cold weather starts

Question 21

21. What is the primary purpose of engine oil lubricant?

Answer 21

Reduce friction

Question 22

22. What is the S.O.A.P. Analysis?

Answer 22

Oil analysis system to trend engine health

Question 23

23. Where are carbon seals used in turbine engines?

Answer 23

Gearboxes
air turbine motor starters
Main shafts

Question 24

24. What is the key purpose of lubrication in a turbine engine?

Answer 24

Lub main shaft bearings

Question 25

25. Where are engine oil filters located?

Answer 25

Between oil pump output & engine bearings

Question 26

26. Why do reciprocating engine require oil with a high viscosity index?

Answer 26

Allow for easier starting in cold temperatures & prevents oil from being too thin

Question 27

27. Why do reciprocating engines require high viscosity oil?

Answer 27

Higher viscosity oil performs better, has high clearances, high operating temp, high bearing pressure

Question 28

28. What two factors impact fluid viscosity?

Answer 28

Temperature & pressure