Module 5,6

Question 1

Define one horsepower (HP) as it relates to ft-lb/min and ft-lb/sec

Answer 1

• Used as a standard unit of mechanical power
• 1HP = 33,000 ft-lb/min
• 1HP = 550 ft-lb/sec

Question 2

Define Indicated HP

Answer 2

HP calculating from the IMEP

Question 3

Define Friction HP

Answer 3

Lost HP due to friction and loads on the engine

Question 4

Define Brake HP

Answer 4

Actual HP that is delivered to the propeller

Question 5

What is the device used to measure BHP?

Answer 5

Dynamometer

Question 6

When calculating IHP, we use PLANK / 33,000 ft-lb/min. What does each letter stand for in PLANK?

Answer 6

P - IMEP
L - Length of stroke in ft.
A - Area of piston or cross-section area of cylinder
N - # of power strokes per minute rpm/2
K - Number of cylinders

Question 7

List the 6 functions of engine oil

Answer 7

• Reduces friction
• Absorbs HEat
• Seals
• Cushions
• Cleans
• Protects against corrosion

Question 8

Define oil viscosity

Answer 8

Resistance to flow

Question 9

Which oil has a higher viscosity, W80 or W100

Answer 9

W100

Question 10

What does the “W” mean in the oil specification W80

Answer 10

Acceptable for cold weather

Question 11

What is the precaution when handling turbine engine synthetic oil?

Answer 11

Use nitrile gloves as it will eat through normal gloves / skin

Question 12

Define oil Flash Point

Answer 12

Point at which a liquid begins to give off ignitable vapors

Question 13

Define oil Fire Point

Answer 13

Temperature at which there are sufficient vapors to support a flame

Question 14

Define oil Cloud Point

Answer 14

Temperature at which its wax content begin to solidify and separate into crystals

Question 15

Define oil Pour Point

Answer 15

Lowest temperature at which it flows or can be poured

Question 16

Which oil system requires a scavenge pump?

Answer 16

Dry Sump

Question 17

Define a constant displacement pump

Answer 17

Moves a fixed volume of fluid per revolution

Question 18

Which oil system component sets maximum oil pressure?

Answer 18

Pressure Relief Valve

Question 19

Which oil system component allows oil to flow in only one direction?

Answer 19

Check Valve

Question 20

Which oil system component is important if the oil filter ever gets plugged?

Answer 20

Bypass valve

Question 21

A compensated oil pressure relief valve incorporates another type of valve. What is the name of that valve?

Answer 21

Thermostatic valve to allow pressurized oil to enter relief valve

Question 22

In a typical engine lubrication system, does the oil go through the oil cooler just before the entering the system or just before it returns to the sump?

Answer 22

Just before entering the system

Question 23

What type of oil filters are one-time use?

Answer 23

Depth, semi depth filtration

Question 24

What type of oil filters are cleanable and re-usable?

Answer 24

screens

Question 25

List 2 oil system instruments that are most important in regard to engine operation

Answer 25

Oil pressure / temperature gauges