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Unit 25 worksheet: Automatic transmissions
Competency unit: AURTTX003 Inspect and service automatic transmissions
Activity summary:
This worksheet will be used as evidence regarding your work within the following competencies:
- Describe the operation of a torque converter.
- Explain automatic transmission gearing and how it is applied.
- Identify automatic transmission hydraulic systems and components.
- Identify automatic transmission service procedures.
Reference material:
Automotive Mechanics: 10e, Chapters 27, 28, 29 and 30.
Safety precautions:
- Personal protective equipment (PPE) must be worn.
- Follow all standard operating procedures (SOP) when using workshop tools and equipment.
- Be aware that hot transmission fluid can cause severe burns to eyes and skin.
- Do not allow transmission fluid to come into contact with your skin.
- Carry out a risk assessment prior to servicing an automatic transmission.
Teacher/supervisor activity record
YES NO
Teacher/ All tasks completed by student supervisor
to complete Tasks performed to standard as outlined in assessment observation checklists
Student evidence provided and attached to this file
Teacher/supervisor comments:
Teacher/supervisor signature:
| Date: | ||
| Activity result | Completed□ | Not yet completed |
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Unit 25 Worksheet
To accompany May & Simpson Automotive Mechanics 10e
© McGraw-Hill Education 2018
2
Student self-assessment record
YES NO
Student Did you find these tasks difficult to complete?
to
complete Did the outcomes of the activity meet your needs?
Were the tasks relevant to the type of work carried out in your workplace?
Did the instruction given to you prior to and during this activity assist you in completing the tasks?
Additional student comments:
Name of workplace:
Student name:
Student signature:
Date:
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Unit 25 Worksheet
To accompany May & Simpson Automotive Mechanics 10e
© McGraw-Hill Education 2018
3
Competency unit: AURTTX003 Inspect and service automatic transmissions
- List and describe the three sections of an automatic transmission. 1.
2.
3.
Section 1: The torque converter
- Identify in the following table the torque converter components labelled in the diagram below:
Component Name
A
B
C
- Which torque converter component is mounted to the drive plate and is driven by the engine?
__________________________________________________________
- What is the purpose of the stator within the torque converter?
Unit 25 Worksheet
To accompany May & Simpson Automotive Mechanics 10e
© McGraw-Hill Education 2018
4
- Explain the operation of the stator one-way clutch.
- Define the term coupling point.
- What is the key factor with regard to the stator and the effectiveness of torque multiplication?
__________________________________________________________
- Look carefully at the diagram below and define the type of converter pictured. Also, state the purpose of the component labelled A.
Section 2: Mechanical gear systems
- List the three main components of a planetary gear train:
- With regard to gears within the transmission, define the following terms:
- Driven
- Driver
Unit 25 Worksheet
To accompany May & Simpson Automotive Mechanics 10e
© McGraw-Hill Education 2018
5
- With reference to the planetary gear system shown below, answer the following questions:
- Name the components:
A.
B.
C.
D.
E.
F.
G.
- Explain what action will happen if the ring gear is held and the sun gear is the driver:
__________________________________________________________
- Which gear connects the ring gear to the sun gear?
__________________________________________________________
- Provide a description of how the gears within the planetary gear system operate:
__________________________________________________________
- In an automatic transmission, how are planetary components held stationary?
__________________________________________________________
Unit 25 Worksheet
To accompany May & Simpson Automotive Mechanics 10e
© McGraw-Hill Education 2018
6
- With reference to the diagram of the transmission below, answer the following questions:
- Identify the components as shown in the transmission diagram:
Component Name Planetary assembly/shaft locked
A
B
C
D
E
- Complete the following table by identifying which band and clutch is applied for each gear ratio in a three-speed automatic transmission:
Ratio Applied
first gear
second gear
third gear
reverse gear
- With regard to a CVT system, what is the result of hydraulic pressure acting on two split pulleys and varying the groove width of each?
__________________________________________________________
Unit 25 Worksheet
To accompany May & Simpson Automotive Mechanics 10e
© McGraw-Hill Education 2018
7
- How is the grip between the drive and the driven members varied in an electromagnetic powder clutch?
__________________________________________________________
Part 3: Hydraulics and controls
- Name the operating components that are located within the transmission hydraulic system:
__________________________________________________________
- Explain the flow of transmission fluid within a simple hydraulic system:
- With reference to the diagram of a transmission hydraulic system below, answer the following questions:
- Name the valve that is controlled by shifting the gear handle?
__________________________________________________________
Unit 25 Worksheet
To accompany May & Simpson Automotive Mechanics 10e
© McGraw-Hill Education 2018
8
- How is the kickdown cam operated?
__________________________________________________________
- What component provides pressure that is proportional to road speed?
__________________________________________________________
- Which application components are controlled by 2–3 shift valves?
__________________________________________________________
- What is the purpose of the secondary regulator?.
__________________________________________________________
- What is the name of the assembly that houses the transmission control valves?
__________________________________________________________
- Name the hydraulic components that are replaced with input sensors on transmissions that use electronic management control.
__________________________________________________________
- List four input sensors that are used on electronically controlled transmissions:
a.
b.
c.
d.
- How are the shift valves controlled on electronically controlled transmissions?
__________________________________________________________
Section 4: Transmission service
- Provide three reasons why it is important to replace transmission fluid in accordance with the manufacturer’s service schedule:
a.
b.
c.
- When servicing a transmission, explain the importance of using the correct fluid to ensure correct and prolonged operation:
Unit 25 Worksheet
To accompany May & Simpson Automotive Mechanics 10e
© McGraw-Hill Education 2018
9
- Provide seven transmission adjustments that may be carried out on an automatic transmission:
a.
b.
c.
d.
e.
f.
g.
- Explain how you would check the operation of a rheostat-type throttle-positioning sensor:
- When conducting a hydraulic pressure check on a transmission, as a general rule, what position should the selector be in?
__________________________________________________________
- Explain how you would perform a ‘stall test’:
- Look carefully at the two faults that are in the following table. Diagnose each fault by completing the blank fields:
| a. | b. Possible problem | c. | Mechanical fault | |
| component | ||||
| d. | 1 | e. Brake switch | ||
| f. | 2 | g. | The vehicle can be started when the | |
| gear selector is in any position |
Unit 25 Worksheet
To accompany May & Simpson Automotive Mechanics 10e
© McGraw-Hill Education 2018