Chapter 21 - Cooling System Operation and Diagnosis

Question 1

Average engine combustion temperatures

Answer 1

1,200°F - 1,700°F

Question 2

Moisture created during combustion process can condense and flow into oil (1 gallon fuel used = 1 gallon water produced)

Answer 2

Engine running at below minimum operating temperature

Question 3

Oxidizes engine oil producing hard carbon and varnish, which can cause sticking plungers. Also thins oil causing excessive oil consumption through combustion since it gets past piston rings and valve guides

Answer 3

Engine running at above maximum operating temperature

Question 4

Can cause combustion temperatures to rise to a point that causes detonation to occur

Answer 4

Engine running at above maximum operating temperature

Question 5

Coolant flow rate

Answer 5

Up to 1 gallon per minute per horsepower the engine produces

Question 6

Controls minimum normal operating temperature in an engine

Answer 6

Thermostat

Question 7

Temperature where thermostat is fully opened

Answer 7

20°F above its opening temperature

Question 8

Allows a small part of the coolant to circulate within the engine during warm-up

Answer 8

Bypass

Question 9

Radiator design used in older vehicles where coolant entered radiator at the top and flowed down, exiting from the bottom

Answer 9

Down-flow Radiator

Question 10

Radiator where coolant flows from one side of the radiator to opposite side

Answer 10

Cross-flow Radiator

Question 11

Amount of heat one horsepower produces

Answer 11

42 BTUs per minute

Question 12

Part of pressure cap that allows coolant to flow back to radiator when coolant cools and contracts

Answer 12

Vacuum Valve

Question 13

Impact of altitude on boiling point

Answer 13

Decrease boiling point 1°F every 550ft increase in altitude

Question 14

1 bar is the equivalent to how much pressure?

Answer 14

14.7 PSI

Question 15

When coolant flows from radiator to cylinder heads before flowing to engine block

Answer 15

Reverse Cooling

Question 16

Type of pump water pump is, which moves large volumes of coolant w/o increasing its pressure

Answer 16

Centrifugal Pump

Question 17

Part of water pump that pulls coolant

Answer 17

Impeller

Question 18

Smoothly curved passage that changes the fluid flow direction with minimum loss in velocity

Answer 18

Water Pump Scroll

Question 19

Allows coolant to leak out of water pump instead of being forced into the bearing

Answer 19

Weep Hole

Question 20

Coolant flows into block under pressure and then crosses the head gasket to the head through main coolant passages beside EACH cylinder

Answer 20

Parallel Flow System

Question 21

Coolant flows around all cylinders on each bank, starting from rear of the block allowing coolant flow across head gasket via main coolant passages, then from head to intake manifold, and finally out from the highest point in engine cooling passages located in front of engine

Answer 21

Series Flow System

Question 22

Lets steam out of engine gasket, block, o head

Answer 22

Bleed Holes and Steam Slits