BC automotive week 4

Technician A says the primary purpose of the engine is to generate power for the vehicle. Technician B says the power is generated on the compression stroke. Who is right?

A only

B only

Both A and B

Neither A nor B

A only

All of the following are typical cylinder head configurations except.

single over head cam

Dual over head cam

Under head cam

Pushrod or cam in block

Under head cam

In a typical gasoline-powered automobile engine, how many piston strokes make up a complete cycle?

1

2

3

4

4

All of the following are common engine block configurations except?

centrifugal

in line

V

opposed

Centrifugal

____ is another name used to describe the engine bottom end.

short block

cylinder block

crank end

lower deck

short block

The piston is connected the crankshaft by the ____.

cylinder bolt

connecting rod

wrist pin

cam lobe

connecting rod

Technician A says that the camshaft controls the valve operation in the engine. Technician B says the crankshaft controls piston operation. Who is right?

A only

B only

Both A and B

Neither A nor B

Both A and B

A revolution or a complete circle is _______ degrees?

90

180

360

720

360

The crankshaft and the camshaft are timed at a ___to ___ ratio.

4:1

2:1

3:1

1:1

2:1

The four strokes of the internal combustion engine are/

Intake, Compression, Power, Exhale

Inhale, Condense, Power, Exhaust

Intake, Compress, Pound, Exhaust

Intake, Compression, Power, Exhaust

Intake, Compression, Power, Exhaust

Pistons typically use ____ compression rings and one oil ring.

2

3

4

1 to 3

2

The automotive term used to describe a cylinder that is not contributing on the power stroke is:

broken

misfire

timing

check engine

Misfire

Technician A says engines with broken timing belts often crank over much faster than normal. Technician B says engines with broken timing belts crank over slower than normal. Who is right?

A only

B only

Both A and B

Neither A nor B

A only

Which of the following tools is used to check mechanical condition of the engine by checking the suction produced by each cylinder on the intake stroke.

compression tester

vacuum gauge

leak down tester

temperature gun

vacuum gauge

A compression test is used to

Verify the mechanical condition of a cylinder in an engine

Locate a cylinder or cylinders with low compression

 Test the compression stroke pressure for each cylinder

all of the above

All of the above

Technician A says that all the spark plugs should be removed when performing a compression test. Technician B says the throttle plate should be held wide open when performing a compression test. Who is right?

A only

B only

Both A and B

Neither A nor B

Both A and B

After a low compression cylinder has been identified a Leakdown test is used to determine:

cylinder compression

cylinder leakage and leak location

test the vacuum produced on the intake stroke

all of the above

cylinder leakage and leak location

Technician A says the purpose of the cooling system is to control the temperature of the engine. Technician B says the purpose of the cooling system is to keep the engine cool by absorbing and removing heat. Who is right?

A only

B only

Both A and B

Neither A nor B

Both A and B

Which of the following is not a true statement about the functions of a cooling system?

It provides a means of warming the passenger compartment

It removes engine heat

It maintains a proper engine operating temperature

It keeps the engine from reaching operating temperature too quickly.

It keeps the engine from reaching operating temperature too quickly.

The heater is used warm the passenger compartment in a vehicle. Warm coolant is circulated through a small heat exchanger call a _____________.

radiator

control valve

 cab warmer

heater core

Heater core

All of the following are acceptable names for the cooling system fluid except.

antifreeze

coolant

refrigerant

engine coolant

Refrigerant

Which component is used to circulate coolant through the engine

radiator

thermostat

water pump

fuel pump

water pump

Which component is used to transfer coolant heat to the outside air?

radiator

thermostat

water pump

fuel pump

radiator

Which component is used to control the temperature of the engine?

radiator

thermostat

water pump

fuel pump

thermostat

All of the following are functions of the radiator cap except.
seals the radiator

holds pressure in the cooling system

 relieves excess pressure from the cooling system

control coolant circulation in the engine block

control coolant circulation in the engine block

For every pound of pressure increase in the cooling system, the boiling point of the coolant will increase ____ degrees Fahrenheit.

2

1

4

3

3

The correct coolant/antifreeze mixture for use in most vehicles is ____.

50% antifreeze/ 50% water

25% antifreeze/75% water

pure ethylene glycol

pure water

50% antifreeze/ 50% water

Technician A says a cooling system pressure test is used to check for cooling system leaks. Technician B says a cooling system pressure tester is used to check for a blown head gasket. Who is right?

A only

B only

Both A and B

Neither A nor B

A only

The combustion chamber is located directly above the piston.

true

false

true

In a four-stroke cycle engine, the crankshaft must make four complete rotations to complete the cycle.

true

false

false

The crankcase is the upper part of the engine block, where the valves are located.

true

false

false

An intake valve is usually smaller than an exhaust valve.

true

false

false

A crank damper helps prevent crankshaft vibration.

true

false

true

One of the functions of antifreeze is to lubricate the water pump.

true

false

true

The radiator's primary function is to store engine heat.

true

false

false

Highest point of piston travel.

TDC top dead center

Caused by ignition of air-fuel mixture.

power stroke

Clears burned gases from cylinder.

exhaust stroke

Results in 180° rotation of crankshaft.

piston stroke

Lowest point of piston travel.

BDC Bottom dead center

Coolant will leak from here when the water pump seal fails

water pump vent hole

Directs air from the fan

radiator shroud

Disk with fan-like blades; spins to produce suction and flow

water pump impeller

Pulls air through the radiator

cooling fan

Permits coolant circulation in the engine when the thermostat is closed

bypass hose

All of the following are typical cylinder head configurations except.

OHC

DOHC

Under Head Cam

Cam in the block

Under head Cam

Technician A says that the camshaft controls the valve operation in the engine. Technician B says the crankshaft controls piston operation. Who is right?

A only

B only

Both A and B

Neither A nor B

Both A and B

Technician A says that the crankshaft and camshaft are timed at a 2:1 ratio. Technician B says that they are timed at a 1:1 ratio. Who is right?

A only

B only

Both A and B

Neither A nor B

A only

The automotive term used to describe a cylinder that is not contributing on the power stroke is:

broken

misfire

timing

check engine

misfire

Technician A says engines with broken timing belts often crank over much faster than normal. Technician B says engines with broken timing belts crank over slower than normal. Who is right?

A only

B only

Both A and B

Neither A nor B

A only

A vacuum gauge:

is used to check the mechanical condition of the engine

 measures intake stroke piston suction

 measures engine vacuum from all the cylinders at the same time

all of the above

all of the above

A compression test is used to check cylinder pressure and verify the engine mechanical condition on which stroke?

Intake

Compression

Power

Exhaust

compression

Technician A says that all the spark plugs should be removed when performing a compression test. Technician B says the ignition system should be disabled when performing a compression test. Who is right?

A only

B only

Both A and B

Neither A nor B

Both A and B

A Leakdown test indicates 80% leakage. The technician can hear leakage out the throttle body. This would most likely indicate a defective

exhaust valve

 head gasket

 piston or rings

intake valve

intake valve