Torque Converter Fundamentals and Service

Question 1

Identify the two major functions of a torque converter.

Answer 1

Torque multiplication

Fluid coupling

Question 2

Identify two torque converter features that help protect the driveline and or transmission.

Answer 2

Shock absorption during engagement reduces powertrain stresses.
Gradual start up of load reduces stress on the driveline and transmission.

Question 3

Vortex flow is the greatest when:

a. the turbine and the impeller are at the same speed.
b. the turbine turns faster than the impeller.
c. torque output is the greatest.
d. torque output is the lowest.

Answer 3

c. torque output is the greatest.

Question 4

Identify the three main torque converter elements.

Answer 4

Impeller
Stator
Turbine

Question 5

A lockup clutch is engaged at low engine rpm to prevent torque converter slippage during those periods when high torque output is required.
True
False

Answer 5

False, medium to high rpm under light load.

Question 6

The clutch disc of a torque converter lockup clutch is connected to:

a. the impeller and turbine.
b. the turbine and stator.
c. the stator and flywheel.
d. the engine flywheel and impeller.

Answer 6

a. the impeller and turbine.

Question 7

The term phase refers to:

a. the number of turbine elements.
b. the amount of torque than can be absorbed by the torque converter.
c. a functional stage.
d. oil circulation

Answer 7

c. a functional stage.

Question 8

The stator is:

a. a stage.
b. a phase.
c. a stationary reactor.
d. engine-driven.

Answer 8

c. a stationary reactor.

Question 9

A torque converter temperature gauge is a very important tool in terms of preventing torque converter damage due to overheating. At what torque converter oil temperature should the machine be shut down and overheating problems investigated?

Answer 9

250F

Question 10

When you test a torque converter for operational problems, test equipment is required. Identify the major concern when using test gauges.

Answer 10

The operating range of the test gauge must be greater than the pressure or temperature expected during the test process.

Question 11

Torque converter overheating problems may be caused by:

a. operator error in transmission gear selection for the operating conditions.
b. low torque converter oil level.
c. a plugged oil cooler.
d. high load operation and/or steep incline operation.
e. any of the above conditions.

Answer 11

e. any of the above.

Question 12

Sometimes the torque converter assembly must be secured to the transmission during the removal process.
True
False

Answer 12

True

Question 13

Once a torque converter is repaired and assembled, it can be placed in storage without protective covers on the oil openings. Dust that gets into the torque converter will be removed at the initial oil change interval.
True
False

Answer 13

False

Question 14

When the output shaft on a torque divider is stalled and the engine is at maximum RPM the turbine is:

a. stopped
b. turning full speed forward
c. turning in reverse

Answer 14

c. turning in reverse

Question 15

Name the major parts of a torque divider?

Answer 15

Single stage torque converter
Single planetary gear set
Torque converter carrier
Torque converter housing

Question 16

The part that is connected to the transmission input shaft if the:

a. turbine
b. stator
c. one way clutch
d. impeller

Answer 16

a. turbine

Question 17

Identify the two types of oil flow and the conditions under which each occurs.

Answer 17

Vortex flow occurs when difference in the impeller and turbine speed is greatest.
Rotary flow occurs when the difference in impeller and turbine speed is slight.

Question 18

Rotary flow in a hydrodynamic drive is:

a. Greatest under heavy load
b. Greatest when torque output is the lowest
c. Directed by the stator
d. Greatest with the turbine stalled.

Answer 18

b. Greatest when torque output is the lowest.

Question 19

The purpose of the stator is to:

a. prevent turbulence.
b. change direction of oil flow.
c. increase speed efficiency.
d. absorb shock loads.

Answer 19

b. Change direction of oil flow.

Question 20

The purpose of a torque converter lockup clutch is:

a. To hold the stator.
b. To obtain a reverse drive.
c. To increase efficiency.
d. To reduce transmission slippage.

Answer 20

C. To increase efficiency.

Question 21

The term stage refers to the number of:

a. one way clutches.
b. stators.
c. turbine elements.
d. independent components.

Answer 21

c. turbine elements.

Question 22

Maximum torque converter output torque occurs when:

a. The impeller is at maximum rpm and the turbine is at one half impeller rpm.
b. the stator is freewheeling.
c. The rotary flow is at maxiumum.
d. The turbine is stopped and the impeller is turning at maximum possible rpm.

Answer 22

d. The turbine is stopped and the impeller is turning at maximum possible rpm.

Question 23

Converter temperature sending units are usually located in:

a. the converter oil inlet.
b. the converter oil outlet.
c. the cooler inlet.
d. the cooler outlet.

Answer 23

b. the converter oil outlet.

Question 24

Identify the two main torque converter mounting methods.

Answer 24

a. Engine mounted.

b. Remote mounted.

Question 25

A high stall speed recorded during the torque converter stall test, would indicate a torque converter or transmission problem. Further testing is required to isolate the exact component at fault.
True
False

Answer 25

True

Question 26

When you remove the torque converter, you do not have to be concerned with the flywheel/torque converter mounting and drive arrangement.
True
False

Answer 26

False, care must be taken to avoid damaging the torque converter or flywheel.

Question 27

The torque converter must be disassembled and reassembled using the instructions provided in the appropriate service manual.
True
False

Answer 27

True

Question 28

After mounting the torque converter unit to the engine, you should make the following check:

a. engine rpm
b. converter rpm
c. converter to flywheel end play.
d. converter output torque.

Answer 28

c. converter to flywheel end play.

Question 29

List three advantages of a torque divider.

Answer 29

a. absorb powertrain shock loads.
b. provide automatic clutching.
c. Multiply engine torque in accordance with output shaft load.