Unit 5 Chapter 12

Front 1

Technician A says multiple springs per valve may be used in engines designed to run at high rpm. Technician B says that the more pressure the valve springs have, the less wear will occur on the other valve train components. Who is correct?

Back 1

Technician A

Front 2

When discussing valve train components, Technician A says stamped rocker arms are very strong and may be used in high-horsepower engines. Technician B says forged rocker arms are used in high-torque, high-horsepower applications. Who is correct?

Back 2

Technician B

Front 3

Which of the following problems can be caused by worn valve guides?

A. Exhaust smoke

B. Excessive engine oil consumption

C. Premature wear on the valve face, seat, and stem

D. All of the answers listed

Back 3

D. All of the answers listed

Front 4

Hardened valve seats are often used for both intake and exhaust ports to accommodate:

Back 4

extreme temperatures.

Front 5

In an L-head (flat head) engine design, where are the valves located?

Back 5

In the block, off to one side of the cylinder

Front 6

What is the purpose of multivalve, hemispherical chamber cylinder heads (3 or 4 valves per cylinder)?

Back 6

To increase the engine's power and efficiency

Front 7

The oval combustion chamber design is also known as:

Back 7

the bathtub.

Front 8

Technician A says solid valve lifters are less likely to contribute to valve float at high rpm than hydraulic lifters. Technician B says roller tip lifters can only be hydraulic because the roller cannot stand hammering against the camshaft. Who is correct?

Back 8

Technician A

Front 9

Technician A says that valve stem seals allow a small amount of oil to seep past them in order to lubricate the valve stems. Technician B says that no oil should seep past properly functioning valve stem seals. Who is correct?

Back 9

Technician A

Front 10

The wedge combustion chamber:

A. has a small combustion chamber surface area.

B. lowers hydrocarbon emissions.

C. has the spark plug placed at the thick end of the wedge.

D. All of the answers listed

Back 10

D. All of the answers listed

Front 11

Which of the following tools should be used to measure valve clearance (lash) with solid valve lifters?

Back 11

Feeler gauge

Front 12

Technician A says generally, sodium-filled valves cannot be repaired or ground and must be replaced if problems occur. Technician B says sodium filled valves have a hollow stem where the sodium is located. Who is correct?

Back 12

Both Technician A and Technician B

Front 13

The proper repair procedure for a valve that has heavy burn marks on its face is to:

Back 13

replace the valve and repair or replace the seat as needed.

Front 14

Technician A says pushrods can best be checked for straightness by rolling them across a very flat surface such as a piece of glass. Technician B says rocker arms must be checked for wear at their valve end, pushrod end, and pivot area. Who is correct?

Back 14

Both Technician A and Technician B

Front 15

To determine if valve springs can be reused, they should be tested for spring height, installed pressure, and:

Back 15

squareness.

Front 16

Which of the following should you be aware of when removing a cylinder head?

Back 16

Some manufacturers require the head bolts to be loosened in a specified pattern.

Front 17

Which of the following tests is used to identify a cylinder head or gasket problem as the cause of engine overheating?

Back 17

Combustion gas detection test

Front 18

Technician A says that valve stem seals allow a small amount of oil to seep past them in order to lubricate the valve stems. Technician B says that no oil should seep past properly functioning valve stem seals. Who is correct?

Back 18

Technician A

Front 19

Which of the following is a characteristic of hydraulic valve lifters?

Back 19

They automatically accommodate changes from part wear or temperature fluctuations.

Front 20

Valve stem-to-guide clearance should be measured using a:

Back 20

dial indicator or micrometer and ball gauge.

Front 21

To begin cylinder head component reassembly, Technician A says valve stems should be coated with clean engine oil or engine assembly lubricant before installing the valves. Technician B says only the valve stem seals need to be lubricated for reassembly. Who is correct?

Back 21

Technician A

Front 22

When discussing cylinder head removal and installation, Technician A says torque-to-yield (TTY) bolts are used to attach cylinder heads in all automotive engines. Technician B says TTY bolts must always be replaced, never reused when reassembling. Who is correct?

Back 22

Technician B

Front 23

In an overhead cam (OHC) cylinder head, two surfaces that must be in alignment are the gasket sealing surface and the:

Back 23

camshaft journal bores.

Front 24

The maximum allowed warpage of the cylinder head gasket surface is typically:

Back 24

0.003″ (0.0762 mm).

Front 25

The main benefit of using roller rocker arms in the valve train is:

Back 25

reduced friction and wear.

Front 26

In this example, a cylinder head's valve guide diameter is specified at 0.250″ (6.35 mm) plus or minus 0.0005″ (0.013 mm). The guide measures at 0.2520″ (6.401 mm).Technician A says the guide must be repaired before returning the cylinder head to service.Technician B says this amount of wear will cause no problem as long as new valve stem seals are installed.Who is correct?

Back 26

Technician A

Front 27

A camshaft follower performs the same function as a:

Back 27

rocker arm.

Front 28

If tools are not available to measure camshaft bore alignment, which of the following methods may be used instead?

Back 28

Verify camshaft straightness and bearing journal size, then install the camshaft and check for binding.

Front 29

Technician A says to check camshaft bearing bore alignment with a dial bore gauge. Technician B says to check camshaft bore alignment using a straightedge and feeler gauge. Who is correct?

Back 29

Technician B

Front 30

During a cylinder leakage test, air leaks into the cooling system (out of the radiator filler neck). What should the next step be?

Back 30

Remove the head and inspect it and the head gasket for leaks.

Front 31

When inspecting a cylinder head, crusty flakes of material are found inside the combustion chambers, typically indicating:

Back 31

worn valve guides or piston rings.

Front 32

The engine installed in a race car would have _______ intake and exhaust ports than an engine designed for low operating speeds.

Back 32

larger

Front 33

Technician A says the gas direct injection (GDI) cylinder head design uses the injected fuel to cool the incoming air. Technician B says GDI engines use substantially more fuel than non-GDI designs. Who is correct?

Back 33

Technician A

Front 34

MLS head gaskets:

are constructed of multiple layers.have strategically located sealing beads.use stainless steel to maintain the correct shape when hot.All of the answers listed

Back 34

All of the answers listed

Front 35

Technician A says aluminum cylinder head surfaces should be scraped clean only with nonmetallic tools to avoid gouging. Technician B says that aluminum heads should also be chemically cleaned according to the manufacturer's recommendations before inspection. Who is correct?

Back 35

Both Techs A and B

Front 36

Which of the following problems can be caused by worn valve guides?

Exhaust smoke Excessive engine oil consumption Premature wear on the valve face, seat, and stem All of the answers listed

Back 36

All of the answers listed

Front 37

Technician A says valve rotators should always be installed on both intake and exhaust valves. Technician B says valve rotators help to prevent hot spots and carbon buildup. Who is correct?

Back 37

Technician B

Front 38

Technician A says a cylinder head made of aluminum alloy cannot be checked for cracks with the Magna-Flux process. Technician B says the aluminum head can be dye tested for cracks and pressure checked for leaks. Who is correct?

Back 38

Both Technician A and Technician B

Front 39

When deciding whether to reuse valve springs, Technician A says a valve spring is sure to have correct pressure if it passes the height and squareness tests. Technician B says a valve spring that is not square can cause premature wear to the guide and stem. Who is correct?

Back 39

Technician B

Front 40

Technician A says using roller rocker arms will reduce wear and friction in the valve train. Technician B says using roller rocker arms will increase fuel economy and performance. Who is correct?

Back 40

Both Technician A and Technician B

Front 41

When discussing intake and exhaust port designs, Technician A says larger ports will increase an engine's torque at low engine speeds. Technician B says larger ports will increase torque at high engine speeds. Who is correct?

Back 41

Technician B

Front 42

What is flame propagation?

Back 42

The movement of the flame front away from the spark plug across the combustion chamber

Front 43

Two technicians are discussing a cracked cast iron head. Technician A says that some cracks can be welded successfully. Technician B says that some cracks can be repaired by pinning them. Who is correct?

Back 43

Both Technician A and Technician B

Front 44

Technician A says that gas-direct injection engines have injectors mounted in the cylinder heads. Technician B says that turbulence in the combustion area creates a better burn of the air/fuel mixture. Who is correct?

Back 44

Both Technician A and Technician B

Front 45

Technician A says that variable valve timing allows better control. Technician B says that in-block cams usually include variable valve timing. Who is correct?

Back 45

Technician A

Front 46

Technician A says that smaller ports and valves in a cylinder head will create more power and torque at high rpm. Technician B says that smaller ports and valves in a cylinder head will create more power and torque at low rpm. Who is correct?

Back 46

Technician B

Front 47

Technician A says that when the lifter is on the base circle of the cam lobe, the valve is closed. Technician B says that the valve has a small amount of clearance when the valve is fully open. Who is correct?

Back 47

Technician A

Front 48

Technician A says that some head bolts can be reused. Technician B says that some head bolts are torqued to their yield point. Who is correct?

Back 48

Both Technician A and Technician B

Front 49

Technician A says that the head gasket is designed to seal between the head and the block. Technician B says that most head gaskets require that you coat them with special sealers before installation. Who is correct?

Back 49

Technician A

Front 50

Technician A says that the cylinder head design determines the output power of the engine. Technician B says that some engines use three valves: one intake and two exhaust. Who is correct?

Back 50

Technician A

Front 51

Technician A says that soft plugs allow the block to expand and contract without cracking. Technician B says that soft plugs will prevent damage to the head or block if coolant freezes. Who is correct?

Back 51

Neither Technician A nor Technician B

Front 52

Technician A says that valve seals are designed to stop combustion gases from entering the valve train area. Technician B says that valve retainers hold the valve in the spring. Who is correct?

Back 52

Technician B

Front 53

Technician A says that an interference angle is the difference in angle between the valve face and valve seat. Technician B says an interference angle is when a piston hits a valve. Who is correct?

Back 53

Technician A