Deck 51: Engine Sealing Gaskets, Fastener Torque

Question 1

The most common valve cover gasket materials are ____________________, synthetic rubber, and silicone.

Answer 1

rubberized cork

Question 2

Which of the following statements is LEAST-Likely true?

A)Modern head gaskets are called permanent torque or non-retorque.
B)The greatest torque gain will occur during the first hour a rebuilt engine is operated.
C)A gasket must be able to maintain a good seal over its lifetime.
D)Small changes in a gasket's thickness can result in a substantial loss of clamping force.

Answer 2

B

Question 3

In some late-model engines, head bolts are purposely torqued to within 2% of their yield point. This method, known as ____________________, provides a more consistent clamping force and the most fatigue resistant joint possible.

Answer 3

torque-to-yield
torque to yield

Question 4

Approximately 90% of the torque applied in tightening a dry, unplated fastener is used to overcome friction.

Question 5

While having a discussion, Technician A says that normal head bolt torque values have a calculated safety factor of about 25% less than the maximum amount a bolt can be torqued without becoming permanently stretched. Technician B says that the safety factor is about 5%. Who is correct?

A)A only
B)B only
C)Both A and B
D)Neither A nor B

Question 6

____________________ is the measurement of the twisting effort required to tighten a fastener.

Question 7

Chemical adhesives are recommended for bolts over 3/8" in diameter.

Question 8

Sheet metal parts often become distorted when bolts are tightened against them during assembly.

Question 9

Tightening to the wrong torque can distort an engine's cylinder block.

Question 10

While having a discussion, Technician A says that clamping force results from the tension or stretch on bolts securing the two pieces together. Technician B says that it results from the springiness of a gasket between parts. Who is correct?

A)A only
B)B only
C)Both A and B
D)Neither A nor B

Question 11

All of the following statements is true EXCEPT:

A)paper gaskets are generally the only gaskets other than retorqueable head gaskets that require a sealer.
B)paper gaskets are found on some timing covers, water pumps, water outlets, oil pump inlet screens, and externally mounted oil pumps.
C)gasket paper can be purchased in sheets.
D)silicone and neoprene gaskets are used with sealers.

Question 12

The clamping load on a fastener is known as ____________________.

Question 13

Which of the following is LEAST-Likely true?

A)RTV silicone is normally used around fuel.
B)Oil pans and valve covers can be soaked in solvent for an hour or so to help soften the RTV for easier removal.
C)Much of the assembly of modern engines is done by robots.
D)Silicone RTV is a popular sealer that is sometimes called silicone rubber.

Question 14

Torque-to-yield bolts do not work well with aluminum heads, which experience greater expansion with heat.

Question 15

____________________ seals are used at the front and the rear of the crankshaft, or the front of an overhead camshaft.

Question 16

The sealer MOST-Likely recommended for use where gaskets join and for sealing water passages in intake manifolds is:

A)acetic acid
B)silicone
C)liquid thread
D)Teflon tape

Question 17

The part that is MOST-Likely a rear seal is the:

A)flywheel bolt
B)rope seal
C)clutch
D)gasket

Question 18

When too much metal has been removed from a head's surface, a ____ can be installed to compensate.

A)gasket
B)plug
C)cork
D)shim

Question 19

All of the following statements are true EXCEPT:

A)Kevlar is more resistant to heat than graphite.
B)composite graphite gaskets require a very smooth surface finish.
C)graphite gaskets can be coated to lengthen their service life.
D)graphite transfers heat from the engine to the coolant more quickly than Kevlar.

Question 20

____ means that the chemical works only in the absence of air.

A)Aerobic
B)Knurling
C)Anaerobic
D)Lugging

Question 21

What are the primary purposes of gasket sealers?

Question 22

How do you get an accurate reading with a torque wrench?

Question 23

List five rules that should be adhered to when using abrasive discs.

Question 24

What are the three methods used to measure the preload on a fastener?

Question 25

When a manifold cracks or a manifold bolt breaks, it is not unusual to find a burned exhaust valve in a port close to the exhaust leak. Why does this occur?