AURTTX010
Overhaul hydrostatic transmissions


Application

This unit describes the performance outcomes required to return a hydrostatic transmission to original manufacturer tolerances and clearances. It involves preparing for the task, dismantling and evaluating the transmission, carrying out the overhaul procedures, reassembling and testing the transmission, and completing workplace processes and documentation.

It applies to those working on hydrostatic transmissions in vehicles from all sectors of the industry.

No licensing, legislative, regulatory or certification requirements apply to this unit at the time of publication.


Elements and Performance Criteria

Elements

Elements describe the essential outcomes.

Performance Criteria

Performance criteria describe the performance needed to demonstrate achievement of the element. Where bold and italicised text is used, further information is detailed in the range of conditions section.

1. Prepare to dismantle hydrostatic transmission

1.1 Job requirements are determined from workplace instructions

1.2 Dismantling information is sourced and interpreted

1.3 Dismantling options are analysed and those most appropriate to the circumstances are selected

1.4 Hazards associated with the work are identified and risks are managed

1.5 Dismantling tools and equipment are selected and checked for serviceability

2. Dismantle and evaluate hydrostatic transmission and components

2.1 Transmission is dismantled in a logical sequence according to manufacturer and workplace procedures, and safety and environmental requirements, and without causing unnecessary damage to components or systems

2.2 Components are cleaned for evaluation according to workplace procedures and safety and environmental requirements

2.3 Components are measured and compared with manufacturer specifications and serviceability is determined

2.4 Component repair method is determined

2.5 Unserviceable parts are identified and replacement parts sourced

3. Carry out overhaul

3.1 Overhaul information is sourced and interpreted

3.2 Overhaul options are analysed and those most appropriate to the circumstances are selected

3.3 Overhaul tools and equipment are selected and checked according for serviceability

3.4 Components are machined, repaired and replaced as required, and adjustments are carried out according to manufacturer specifications, workplace procedures, and safety and environmental requirements, and without causing damage to components or systems

4. Assemble transmission and components

4.1 Transmission is assembled according to manufacturer specifications, workplace procedures, and safety and environmental requirements

4.2 Tolerances and clearances are measured against manufacturer specifications and necessary adjustments are made

4.3 Assembly of transmission is completed within workplace timeframes and without causing damage to other components or systems

4.4 Post-assembly testing is carried out according to workplace procedures and safety and environmental requirements, and any problems detected as having been introduced during the assembly process are rectified

5. Complete work processes

5.1 Final inspection is made to ensure work is to workplace expectations and transmission is presented ready for use or storage

5.2 k area is cleaned, waste and non-recyclable materials are disposed of, and recyclable material is collected

5.3 Tools and equipment are checked and stored according to workplace procedures

5.4 Workplace documentation is processed according to workplace procedures

Evidence of Performance

Before competency can be determined, individuals must demonstrate they can perform the following according to the standards defined in this unit’s elements, performance criteria, range of conditions and foundation skills:

overhaul three different hydrostatic transmissions.


Evidence of Knowledge

Individuals must be able to demonstrate knowledge of:

work health and safety (WHS) and occupational health and safety (OHS) requirements relating to overhauling hydrostatic transmissions, including procedures for using:

specialised hydrostatic transmission overhaul tools, equipment and machinery

chemicals and toxic substances

manual and mechanical lifting equipment

environmental requirements, including procedures for trapping, storing and disposing of fluids released from hydrostatic transmissions

types, characteristics and operating principles of hydrostatic transmissions

hydrostatic transmission overhaul procedures, including:

methods for cleaning and preparing hydrostatic transmissions for overhaul

transmission dismantling procedures

transmission component inspection, measuring and evaluation procedures, including:

transmission case damage

measuring tolerances and clearances of components

transmission component repair and adjustment procedures, including procedures for removing and replacing components

transmission assembly procedures, including procedures for adjusting component tolerances

post-overhaul testing procedures for hydrostatic transmissions.


Assessment Conditions

Assessors must satisfy NVR/AQTF assessor requirements.

Competency is to be assessed in the workplace or a simulated environment that accurately reflects performance in a real workplace setting.

Assessment must include direct observation of tasks.

Where assessment of competency includes third-party evidence, individuals must provide evidence that links them to the hydrostatic transmissions that they have worked on, e.g. repair orders.

Assessors must verify performance evidence through questioning on skills and knowledge to ensure correct interpretation and application.

The following resources must be made available:

mechanical repair workplace or simulated workplace

workplace instructions

manufacturer hydrostatic transmission specifications

three different hydrostatic transmissions requiring overhaul

tools, equipment and materials appropriate for overhauling and adjusting hydrostatic transmissions.


Foundation Skills

This section describes those language, literacy, numeracy and employment skills that are essential to performance and are not explicit in the performance criteria.

Skills

Description

Learning skills to:

locate sources of information for hydrostatic transmissions efficiently.

Reading skills to:

interpret and assess information from manufacturer and workshop literature when seeking hydrostatic transmission specifications and procedures.

Writing skills to:

legibly and accurately fill out workplace documentation when reporting diagnostic findings, making repair recommendations, and recording parts and material used.

Oral communication skills to:

clarify instructions, report evaluation findings and make overhaul recommendations.

Numeracy skills to:

measure hydrostatic transmission components and use basic mathematical operations, including addition, subtraction, multiplication and division, to calculate distances, areas, volumes, tolerances and deviations from manufacturer specifications.

Planning and Organising skills to:

plan own work requirements and prioritise and sequence actions to achieve required outcomes and ensure tasks are completed within workplace timeframes.

Technology skills to:

use precision measuring equipment, such as vernier calipers and micrometers

use specialised hydrostatic transmission overhaul equipment, such as pressure gauges.


Range Statement

This section specifies work environments and conditions that may affect performance. Essential operating conditions that may be present (depending on the work situation, needs of the candidate, accessibility of the item, and local industry and regional contexts) are included. Bold italicised wording, if used in the performance criteria, is detailed below.

Safety and environmental requirements must include:

work health and safety (WHS) and occupational health and safety (OHS) requirements, including procedures for using:

specialised hydrostatic transmission overhaul tools, equipment and machinery

chemicals and toxic substances

manual and mechanical lifting equipment

environmental requirements, including procedures for trapping, storing and disposing of fluids released from hydrostatic transmissions.


Sectors

Technical - Transmission


Competency Field

Mechanical Miscellaneous