Question 1

List three types of valve springs.

Accepted Answer

There are several types of valve springs including: uniform pitch variable pitch basket coil (variable rate) beehive mechanical vibration dampeners

Question 2

Technician A says intake valves take the most punishment and should always be replaced whenever in doubt. Technician B says many exhaust valve stems have a welded on hardened tip. Who is right?

Accepted Answer

Exhaust valves typically endure more extreme temperatures and conditions compared to intake valves, leading to the practice of welding a hardened tip on many exhaust valve stems to increase durability and wear resistance. Technician A's statement is incorrect because it is generally the exhaust valves that take more punishment due to higher temperatures and corrosive gases they are exposed to.

Question 3

Springs that have been overheated will stretch and be longer.

Accepted Answer

Overheating can cause the metal to weaken and lose its elasticity, causing the spring to stretch and become longer.

Question 4

Technician A says springs should be tested for squareness, tension, and height. Technician B says to stack VSI shims under a valve spring until the spring pressure is correct. Who is correct?

Accepted Answer

Technician A is correct. Springs should be tested for squareness, tension, and height to ensure proper operation. Technician B's method of using stacked shims to adjust spring pressure is not a recommended practice as it can lead to uneven pressure distribution and premature valve wear.

Question 5

Technician A says heating a pressed-fit stud before installing it into the head makes installation easier. Technician B says stud-mounted rockers are oiled through hollow pushrods. Who is right?

Accepted Answer

The answer of Technician A says heating a pressed-fit stud...

Question 6

What is the margin of a valve?

Accepted Answer

The answer of What is the margin of a valve?...

Question 7

Valves will contract as they warm up during use.

Accepted Answer

Valves are made of metal and metal expands as it heats up. Therefore, valves will contract as they warm up during use.

Question 8

Technician A says valve stems are often coated with Teflon. Technician B says chrome is the popular stem coating in Europe. Who is correct?

Accepted Answer

Neither technician is correct. Common valve stem coatings include chrome, nickel, and titanium nitride, but Teflon is not typically used. Additionally, there is no evidence to suggest that chrome is more popular in Europe than other coatings.

Question 9

What typically causes damage to the valve head?

Accepted Answer

The answer of What typically causes damage to the valve...

Question 10

In reference to the valve-face angle, what is the purpose of a flatter interference angle?

Accepted Answer

The answer of In reference to the valve-face angle, what...

Question 11

Technician A says there are pushrods available you can cut to length. Technician B says some Ford engines are originally equipped with different length pushrods. Who is correct?

Accepted Answer

Both technicians are correct. Pushrods are available that can be cut to length, and some Ford engines are originally equipped with different length pushrods.

Question 12

Install O-ring seals after the springs.

Accepted Answer

Installing O-ring seals after the springs ensures proper sealing and prevents leakage.

Question 13

Technician A says that basket-type coil springs are installed with the tighter part of the coil against the head. Technician B says grinding a valve seat will not affect the installed height of the valve spring. Who is correct?

Accepted Answer

The answer of Technician A says that basket-type coil springs...

Question 14

Technician A says that weak valve springs can impede heat transfer between the valve faces and seats. Technician B says that wear can be evident on the top when a valve spring has too little tension. Who is correct?

Accepted Answer

The answer of Technician A says that weak valve springs...

Question 15

When grinding valve seats, some machinists will grind the 45-degree angle after the 60-degree angle.

Accepted Answer

This is known as a "three-angle valve job" and involves grinding the 45-degree angle last to ensure a consistent and smooth transition between the seat and the valve face.

Question 16

Valve springs are being discussed. Technician A says you should discard a 2" spring that is 1/16" out of square. Technician B says out-of-square springs can cause uneven valve guide wear. Who is correct?

Accepted Answer

Technician B is correct; out-of-square springs can cause uneven valve guide wear. Technician A's statement about discarding a 2" spring that is 1/16" out of square is not necessarily correct without further information about the specific application and manufacturer's specifications.

Question 17

Technician A says there is no need to lubricate the valve stems upon reassembly. Technician B says intake and exhaust seals are the same materials and shapes. Who is correct?

Accepted Answer

Both technicians are incorrect. Valve stems should be lubricated upon reassembly, and intake and exhaust seals are different materials and shapes.

Question 18

How have manufacturers and machine shops solved the problem of valve seat recession?

Accepted Answer

The answer of How have manufacturers and machine shops solved...

Question 19

Technician A says the first angle cut conventionally is the throat. Technician B says sometimes valve seat angles (3) are cut at the same time with a special cutter. Who is correct?

Accepted Answer

Technician B is correct. The valve seat angles can indeed be cut at the same time with a special cutter, which is a common practice in modern engine rebuilding. Technician A is incorrect, as the first angle cut conventionally is not always the throat, and can vary depending on the engine and valve design.

Question 20

Cam-in-block engines use pushrods to transmit motion from the lifters to the rocker arms.

Accepted Answer

Cam-in-block engines use pushrods to transmit motion from the lifters to the rocker arms.

Quiz 8: Cylinder Head: Springs, Valves, and Valve Seats

List three types of valve springs.

Technician A says intake valves take the most punishment and should always be replaced whenever in doubt. Technician B says many exhaust valve stems have a welded on hardened tip. Who is right?

Springs that have been overheated will stretch and be longer.

Technician A says springs should be tested for squareness, tension, and height. Technician B says to stack VSI shims under a valve spring until the spring pressure is correct. Who is correct?

Technician A says heating a pressed-fit stud before installing it into the head makes installation easier. Technician B says stud-mounted rockers are oiled through hollow pushrods. Who is right?

What is the margin of a valve?

Valves will contract as they warm up during use.

Technician A says valve stems are often coated with Teflon. Technician B says chrome is the popular stem coating in Europe. Who is correct?

What typically causes damage to the valve head?

In reference to the valve-face angle, what is the purpose of a flatter interference angle?

Technician A says there are pushrods available you can cut to length. Technician B says some Ford engines are originally equipped with different length pushrods. Who is correct?

Install O-ring seals after the springs.

Technician A says that basket-type coil springs are installed with the tighter part of the coil against the head. Technician B says grinding a valve seat will not affect the installed height of the valve spring. Who is correct?

Technician A says that weak valve springs can impede heat transfer between the valve faces and seats. Technician B says that wear can be evident on the top when a valve spring has too little tension. Who is correct?

When grinding valve seats, some machinists will grind the 45-degree angle after the 60-degree angle.

Valve springs are being discussed. Technician A says you should discard a 2" spring that is 1/16" out of square. Technician B says out-of-square springs can cause uneven valve guide wear. Who is correct?

Technician A says there is no need to lubricate the valve stems upon reassembly. Technician B says intake and exhaust seals are the same materials and shapes. Who is correct?

How have manufacturers and machine shops solved the problem of valve seat recession?

Technician A says the first angle cut conventionally is the throat. Technician B says sometimes valve seat angles (3) are cut at the same time with a special cutter. Who is correct?

Cam-in-block engines use pushrods to transmit motion from the lifters to the rocker arms.