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Flashcards in Lubrication Deck (27):
1

What are the functions of lubricating oil in reciprocating engines

To reduce friction between moving parts and remove heat

2

Name two important characteristics of aircraft engine oil

Oil must be light enough to circulate freely but heavy enough to provide the proper oil film at engine operating temperatures

3

What could happen to an oil that is too low in viscosity at normal engine operating temperatures

becomes thin and the oil film between moving parts is easily broken, resulting in premature wear

4

What are some of the factors that must be considered by an engine manufacturer in determining the proper grade of oil for particular engine

Operating load and temperature as well as the rotational speed

5

Why do aircraft reciprocating engines use a relatively high viscosity oil

large operating clearance and operate at high temperatures and pressure

6

Name some oil contaminants

Metal particles, dirt, carbon, moisture and acids

7

What is possible indication of low oil pressure together with high oil temperature

A low oil supply

8

Why do oil reservoirs have expansion space

To provide for oil foaming, thermal expansion, and air in the return oil

9

What could cause oil foaming

Diluted oil, contaminated oil, and the oil level is too high

10

What controls oil pressure in a gear type oil pressure pump

Oil pressure relief valve

11

What function does an oil cooler bypass valve perform

It directs the oil either through the cooler or around it in order to maintain proper operating oil temperatures

12

What could be a possible indication if the oil cooler passage becomes obstructed

A high oil temperature

13

Where is the oil temperature bulb usually located

At the engine oil inlet

14

What type of oil is used in a turbine engine oil system

Synthetic oil

15

Where is the most critical point of lubrication in a gas turbine engine

At the turbine bearing

16

What should be done if metal particles are found in an engine oil filter

Follow engine manufacturers maintenance instructions

17

Name two types of turbine engine oil coolers

Air and fuel cooled

18

What does the presence of metal particles in an engine oil filter indicate

usually indicates abnormal wear and possible engine internal failure

19

What is the weight of aircraft engine oil

Approximately 7.5 pounds per U.S gallons

20

What is the primary purpose of engine oil lubricate

To reduce friction.

21

What is straight mineral oil

It is a lubricating oil and does not have any additives

22

Is automotive oil suitable for aircraft engines

No

23

Where can you find the grade of engine oil specified for a particular aircraft

Aircraft flight manual or pilots operating handbook for the aircraft

24

What two instruments show the condition of a reciprocating engine lubrication system

Oil pressure and oil temperature gauge

25

What type of oil quantity indicator is used in most aircraft engines

Dipstick that measures the quantity of the oil in the tank sump

26

When should the engine oil quantity be checked on a turbine engine

As soon as possible after engine is shut down

27

A reciprocating engine is found to have excessive oil consumption without evidence of any oil leaks. Heat is the likely cause

Piston rings are worn or broken