Routine Chassis Maintenance and Alignment for SS 3

Class: SSS 3
Term: First Term
Week: 1
Age: 16 years
Duration: 45 minutes
Subject: Auto Mechanic Work
Curriculum Theme: Routine Chassis Maintenance and Alignment
Previous Lesson:
Topic: ROUTINE MAINTENANCE OF THE CHASSIS
Subject Matter: Chassis alignment, maintain and adjust coupings; Chassis joints e.g permanent joints, temporary joints; Engine mountings, suspension units

Specific Objectives

By the end of the lesson, pupils/students should be able to:

Cognitive Domain

• Define chassis alignment.
• State the importance of routine chassis maintenance.
• Identify different types of chassis joints.
• Describe the function of engine mountings and suspension units.

Affective Domain

• Appreciate the importance of proper chassis maintenance for vehicle safety.
• Develop an interest in practical auto mechanic work.

Psychomotor Domain

• Demonstrate the basic steps of chassis alignment.
• Inspect chassis joints, engine mountings, and suspension units.
• Adjust coupings as required.

Reference Materials

The following resources were used in planning this lesson:

• 2025 Revised 9 Years Basic Education Curriculum
• Relevant State Unified Scheme of Work
• Auto Mechanic Work for Senior Secondary Schools, Textbook 3
• The HeadTeacher Scheme of work

Instructional Materials

The teacher will teach this lesson with the aid of:

• Live vehicle or chassis model
• Toolbox with relevant tools (e.g., wrenches, alignment tools)
• Charts illustrating chassis components and alignment procedures
• Posters showing different types of joints and mountings

Rationale for the Lesson

This lesson is essential for students to understand the fundamental principles of maintaining a vehicle’s structural integrity and handling. It provides practical knowledge and skills necessary for ensuring vehicle safety and extending its lifespan. Mastering these routine maintenance tasks is crucial for aspiring auto mechanics.

Prerequisite/Previous Knowledge

Students should have basic knowledge of vehicle components and general workshop safety rules.

Lesson Content/Board Summary

ROUTINE MAINTENANCE OF THE CHASSIS

Chassis Alignment

Chassis alignment refers to the process of adjusting the angles of the wheels and suspension components to ensure they are set to the manufacturer’s specifications. Proper alignment is crucial for safe handling, even tyre wear, and fuel efficiency.

Key aspects of chassis alignment include:

1. Camber: The inward or outward tilt of the wheel when viewed from the front.
2. Caster: The angle of the steering axis when viewed from the side.
3. Toe: The inward or outward angle of the wheels when viewed from above.

Maintenance and Adjustment of Couplings

Couplings are mechanical devices that connect two shafts together at their ends for the purpose of transmitting power. In a chassis, they often refer to connections within the steering or suspension system that require periodic inspection and adjustment to prevent looseness and ensure proper function.

Maintenance involves:

1. Regular inspection for wear, corrosion, or damage.
2. Lubrication of moving parts as specified by the manufacturer.
3. Tightening of fasteners to correct torque specifications.
4. Adjustment to eliminate excessive play or misalignment.

Chassis Joints

Chassis joints connect different parts of the vehicle frame and suspension system. Their integrity is vital for structural strength and vehicle performance.

1. Permanent Joints: These are joints designed to be fixed and not easily disassembled without damage. They provide structural rigidity.
1. Examples: Welded joints, riveted joints.
2. Maintenance: Inspection for cracks, corrosion, or signs of fatigue. Repair involves re-welding or re-riveting by skilled technicians.
2. Temporary Joints: These joints allow for movement or are designed to be disassembled for maintenance or repair.
1. Examples: Bolted joints, universal joints (U-joints), ball joints, tie rod ends.
2. Maintenance: Regular inspection for wear, looseness, or damage. Lubrication (for U-joints and some ball joints), tightening of bolts, and replacement of worn components are common maintenance tasks.

Engine Mountings

Engine mountings are components that secure the engine to the vehicle’s chassis. They absorb vibrations and shocks from the engine, preventing them from being transmitted to the cabin and ensuring a smoother ride.

Maintenance involves:

1. Inspection for cracks, tears, or excessive compression in the rubber or hydraulic components.
2. Checking for looseness of mounting bolts.
3. Replacement of worn or damaged mountings to prevent excessive engine movement and vibration.

Suspension Units

Suspension units connect the vehicle’s wheels to its body, allowing relative motion between the two. They absorb road shocks, maintain tyre contact with the road, and contribute to vehicle stability and handling.

Common suspension components include:

1. Shock absorbers/struts
2. Springs (coil springs, leaf springs, torsion bars)
3. Control arms
4. Bushings
5. Stabiliser bars

Maintenance involves:

1. Regular inspection of shock absorbers for leaks or damage.
2. Checking springs for cracks or sagging.
3. Inspecting control arms and bushings for wear or damage.
4. Lubricating components where applicable.
5. Replacing worn or damaged parts to restore ride comfort and handling.

Teaching Methods/Instructional Techniques

Discussion, Demonstration, Guided Practice, Question and Answer, Explanation, Observation, Practical Activity

Instructional Procedures

Step 1: Introduction

Time: 5 minutes

Teaching Skill: Elicitation/Engagement

Teacher’s Activity: The teacher greets the students and asks them to recall the importance of regular vehicle maintenance. The teacher then introduces the topic of routine chassis maintenance and alignment as a critical aspect of overall vehicle care.

Pupils’ Activity: Students respond to the questions and listen attentively to the introduction.

Learning Point: Importance of vehicle maintenance

Step 2: Explanation of Chassis Alignment

Time: 8 minutes

Teaching Skill: Explanation/Demonstration

Teacher’s Activity: The teacher defines chassis alignment, explains its purpose, and uses charts or a live vehicle to point out the components involved (e.g., wheels, suspension). The teacher briefly explains camber, caster, and toe.

Pupils’ Activity: Students observe the demonstration and ask questions for clarification.

Learning Point: Chassis alignment definition

Step 3: Demonstration of Basic Alignment Steps

Time: 7 minutes

Teaching Skill: Practical Demonstration

Teacher’s Activity: Using a live vehicle or chassis model, the teacher demonstrates basic visual checks for alignment issues and explains how adjustments would typically be made, emphasising safety.

Pupils’ Activity: Students closely observe the practical demonstration and note key steps.

Learning Point: Basic alignment procedures

Step 4: Chassis Joints and Couplings

Time: 7 minutes

Teaching Skill: Explanation/Identification

Teacher’s Activity: The teacher explains the concept of chassis joints, differentiating between permanent and temporary joints with examples (e.g., welds, bolts, U-joints). The teacher also explains the role of coupings and their maintenance.

Pupils’ Activity: Students identify different types of joints and coupings as explained.

Learning Point: Types of chassis joints

Step 5: Engine Mountings and Suspension Units

Time: 6 minutes

Teaching Skill: Explanation/Description

Teacher’s Activity: The teacher describes the function and importance of engine mountings and suspension units. Using visual aids, the teacher points out these components on the vehicle/model and explains common maintenance checks.

Pupils’ Activity: Students listen and observe, understanding the function of these components.

Learning Point: Engine, suspension functions

Step 6: Guided Inspection and Practice

Time: 5 minutes

Teaching Skill: Guided Practice/Observation

Teacher’s Activity: The teacher guides students to visually inspect accessible chassis joints, engine mountings, and suspension units on the vehicle, pointing out signs of wear or damage. Students are encouraged to identify components.

Pupils’ Activity: Students actively participate in the guided inspection, identifying components and potential issues.

Learning Point: Component inspection practice

Step 7: Evaluation/Review

Time: 5 minutes

Teaching Skill: Questioning/Assessment

Teacher’s Activity: The teacher evaluates the learning by asking the following questions:

1. What is chassis alignment?
2. Mention two types of chassis joints.
3. State one importance of routine chassis maintenance.
4. How do engine mountings contribute to vehicle comfort?

Pupils’ Activity: Pupils answer orally and in writing.

Learning Point: Chassis maintenance understanding

Step 8: Note-Taking

Time: 4 minutes

Teaching Skill: Guided Writing

Teacher’s Activity: The teacher guides pupils/students to copy the essential Board Summary notes on chassis alignment, joints, mountings, and suspension units into their notebooks.

Pupils’ Activity: Pupils/students copy the notes carefully into their notebooks.

Learning Point: Recording lesson notes

Step 9: Conclusion

Time: 3 minutes

Teaching Skill: Consolidation

Teacher’s Activity: The teacher summarises the key points of the lesson, reiterating the importance of routine chassis maintenance for vehicle safety and performance. The teacher encourages students to continue exploring practical aspects of auto mechanics.

Pupils’ Activity: Students listen and reflect on the lesson’s main points.

Learning Point: Lesson summary reinforcement

Continuous Assessment/Further Study

Type: Homework

Instruction: Research and write short notes on the following:

1. The tools specifically used for wheel alignment in a modern workshop.
2. The consequences of driving a vehicle with severely misaligned chassis.
3. List three common signs of worn engine mountings.
4. Identify two types of suspension systems and their main components.

Lesson Keywords

• Chassis – The main frame of a vehicle, supporting the engine and body.
• Alignment – Adjusting the angles of wheels and suspension to manufacturer specifications.
• Couplings – Mechanical devices connecting shafts or components.
• Joints – Connections between parts of the chassis.
• Permanent Joints – Fixed connections like welds or rivets.
• Temporary Joints – Disassemblable connections like bolts or ball joints.
• Engine Mountings – Components securing the engine to the chassis and absorbing vibrations.
• Suspension Units – System connecting wheels to the body, absorbing shocks.

Differentiation

Support for weaker learners: Provide simplified diagrams of chassis components and alignment concepts. Pair them with stronger students during practical observation. Offer additional guided practice on identifying components.

Extension for faster learners: Challenge them to research advanced chassis alignment techniques or the impact of different suspension types on vehicle performance. Encourage them to identify specific vehicle models that use particular types of joints or mountings.

Suggested Lesson Videos

For visual demonstrations of chassis maintenance and alignment, search on YouTube for: chassis maintenance alignment auto mechanic SS3

Teacher Guide for Using This Lesson Plan

Before the lesson, ensure a live vehicle or a chassis model is available for practical demonstration. Prepare charts and posters illustrating chassis components, different types of joints, engine mountings, and suspension units. Emphasise workshop safety rules throughout the lesson, especially during practical activities. Follow the teaching sequence, allowing sufficient time for explanations and student observation. During Step 6, encourage active participation and questioning from students. Ensure all students copy the Board Summary notes accurately in Step 8. Conclude by reinforcing the practical importance of the lesson for future auto mechanics.