Introduction
Introduction
Vehicles are important in everyday transportation. To keep vehicles functioning properly, regular engine maintenance is necessary. Without proper maintenance, engines may overheat, consume too much fuel, or become damaged. Automotive technicians must know the proper ways of inspecting and maintaining engine parts to ensure safety and good vehicle performance.
This lesson will help students understand the importance of engine maintenance and develop practical automotive servicing skills.
Motivation
The teacher will ask the following questions:
- Have you seen someone checking the engine of a car?
- What do you think will happen if engine oil is not checked regularly?
- Why is vehicle maintenance important? The teacher will allow students to share their ideas and experiences.
Presentation of the Lesson
Discussion
A. Basic Parts of a Car Engine and Their Functions
1. Engine Block
The engine block is considered the main body of the engine. It contains the cylinders and other important internal parts of the engine.
Function:
- Supports engine components
- Houses the pistons and cylinders
2. Piston
The piston moves up and down inside the cylinder during engine operation.
Function:
- Produces power through combustion
- Transfers force to the crankshaft
3. Spark Plug
The spark plug creates the spark needed to ignite the fuel-air mixture.
Function:
- Starts combustion inside the engine
- Helps the engine run smoothly
4. Radiator
The radiator helps cool the engine by circulating coolant.
Function:
- Prevents engine overheating
- Maintains proper engine temperature
5. Battery
The battery provides electrical power to start the vehicle.
Function:
- Supplies electricity
- Powers lights and electrical systems
Let's take a closer look on how the car engine works through this video!
Task
Task / Performance Activity
Title: Basic Engine Maintenance Inspection
Objective
The students will apply the knowledge and skills learned in basic car engine maintenance by performing a simple engine inspection.
Instructions
Students will work in groups of 4–5 members. Each group will inspect a vehicle or engine model and perform the following tasks:
-
Identify the basic engine parts:
-
Engine Block
-
Battery
-
Radiator
-
Spark Plug
-
Dipstick
-
-
Check the engine oil level using the dipstick.
-
Inspect the coolant level of the radiator.
-
Observe the battery condition and check for dirt or corrosion.
-
Demonstrate proper workshop safety procedures while performing the activity.
Materials Needed
-
Vehicle or engine model
-
Gloves
-
Safety goggles
-
Clean cloth
-
Checklist form
Output
Each group must:
-
Demonstrate the proper inspection procedures.
-
Submit a short written report about their observations.
-
Explain the importance of each maintenance procedure.
Guide Questions
-
Why is engine oil important?
-
What happens when coolant is low?
-
Why should battery terminals be clean?
-
What safety precautions did your group follow?
Scoring Rubric
| Criteria | Excellent (5) | Good (4) | Fair (3) | Needs Improvement (2) |
|---|---|---|---|---|
| Correct Procedure | Performed all steps correctly | Minor mistakes | Some incorrect steps | Many incorrect steps |
| Safety Practices | Followed all safety rules | Few reminders needed | Sometimes unsafe | Unsafe practices observed |
| Teamwork | All members participated | Most participated | Few participated | Lack of cooperation |
| Explanation | Clear and complete explanation | Good explanation | Limited explanation | Poor explanation |
Total Score: 20 Points
Process
Step 1: Air and Fuel Enter the Engine
The engine takes in air through the air intake while fuel is supplied from the fuel tank. The air and fuel mix together inside the cylinder.
Step 2: Compression of Air and Fuel
The piston moves upward inside the cylinder and compresses the air-fuel mixture. Compression makes the mixture more powerful for combustion.
Step 3: Spark Plug Ignites the Mixture
The spark plug creates a spark that ignites the compressed air-fuel mixture. This produces a small explosion inside the cylinder.
Step 4: Power is Produced
The explosion pushes the piston downward with great force. This movement produces power that helps move the vehicle.
Step 5: Crankshaft Rotates
The piston is connected to the crankshaft. As the piston moves up and down, the crankshaft rotates and transfers power to the wheels.
Step 6: Exhaust Gases Exit
After combustion, the exhaust valve opens and releases the burned gases through the exhaust system.
Step 7: Cycle Repeats
The process repeats continuously while the engine is running to keep the vehicle moving.
The Four-Stroke Cycle of an Engine
-
Intake Stroke – Air and fuel enter the cylinder.
-
Compression Stroke – The piston compresses the mixture.
-
Power Stroke – Spark plug ignites the mixture to create power.
-
Exhaust Stroke – Burned gases leave the engine.
Simple Explanation
A car engine works by burning fuel inside the cylinders to create power. The power moves the pistons, rotates the crankshaft, and makes the wheels move.
Illustration of Engine Cycle
f(x)=\text{Intake}\rightarrow\text{Compression}\rightarrow\text{Power}\rightarrow\text{Exhaust}
Let's take a look on how the 4 stroke cycle works!
Evaluation
A. Identification
Write the correct answer on the space provided.
-
It creates the spark needed to ignite the air-fuel mixture.
-
It is the main body of the engine that contains the cylinders.
-
It helps cool the engine and prevents overheating.
-
It supplies electrical power to start the vehicle.
-
It is used to check the level of engine oil.
B. Enumeration
Enumerate the four-stroke cycle of a car engine.
C. Short Answer
-
Why is regular engine maintenance important?
-
What may happen if engine oil is too low?
-
Why should safety precautions always be followed in automotive work?
D. Practical Test
The students will individually demonstrate the following:
-
Proper checking of engine oil using the dipstick
-
Proper inspection of coolant level
-
Proper use of safety equipment
Scoring Rubric for Practical Test
|
Criteria |
5 Points |
3 Points |
1 Point |
|---|---|---|---|
|
Procedure |
Performed all steps correctly |
Minor mistakes |
Incorrect procedure |
|
Safety |
Followed all safety rules |
Few reminders needed |
Unsafe practices |
|
Tool Handling |
Proper use of tools |
Some errors |
Improper handling |
|
Explanation |
Clear explanation |
Limited explanation |
Unable to explain |
Total: 20 Points
Conclusion
Basic car engine maintenance is an important skill in automotive technology. Understanding how a car engine works and learning the proper ways of checking engine oil, coolant, and battery condition help maintain vehicle performance and prevent serious engine problems. Regular maintenance also improves safety, fuel efficiency, and the lifespan of the vehicle. By following proper procedures and safety precautions, students can develop responsible work habits and practical skills that are useful in the automotive industry and everyday life.
Credits
Credits
-
Department of Education (DepEd) – Technical-Vocational-Livelihood (TVL) Curriculum
-
Automotive Technology Learning Modules and Workshop Demonstrations
Teacher Page
Subject: Automotive Technology
Topic: Basic Car Engine Maintenance
Grade Level: Senior High School (Grade 11–12)
Time Duration: 1 Hour and 30 Minutes
Teacher’s Objectives
The teacher should guide the students to:
-
Identify the basic parts of a car engine.
-
Explain the functions of engine components.
-
Demonstrate proper engine maintenance procedures.
-
Practice safety and responsibility inside the automotive workshop.
Teacher’s Preparation
Before the class begins, the teacher should prepare the following:
-
Vehicle or engine model
-
Automotive tools and equipment
-
Gloves and safety goggles
-
Cleaning cloth
-
Multimedia presentation
-
Printed activity sheets and evaluation forms
The teacher should also inspect the workshop area to ensure cleanliness and safety.
Teaching Strategies
The teacher will use:
-
Discussion Method
-
Demonstration Method
-
Hands-on Activity
-
Cooperative Learning
Teacher’s Procedure
1. Opening Prayer
The teacher will ask a student to lead the prayer.
2. Classroom Management
-
Check attendance.
-
Remind students about workshop rules and safety precautions.
-
Prepare students for the lesson.
3. Review
The teacher will ask review questions related to previous lessons about automotive tools and safety practices.
Example Questions:
-
What are the basic safety rules in the workshop?
-
Why is proper tool handling important?
4. Motivation
The teacher will show pictures or a short video about car engine maintenance and ask students:
-
What do you think happens inside a car engine?
-
Why should engines be maintained regularly?
5. Lesson Discussion
The teacher will discuss:
-
Basic parts of the engine
-
Functions of engine parts
-
Four-stroke cycle
-
Importance of maintenance
-
Safety precautions
The teacher will explain each topic clearly and provide real-life examples.
Demonstration
The teacher will demonstrate:
-
Proper checking of engine oil
-
Coolant inspection
-
Battery inspection
-
Safe use of automotive tools
Students will observe carefully before performing the activity.
Classroom Activity
The teacher will divide the students into groups and assign tasks related to engine inspection and maintenance.
The teacher will supervise and assist students during the activity.
Evaluation Guide
The teacher will:
-
Give written and practical tests
-
Observe students’ performance
-
Use a rubric to evaluate skills, safety practices, and participation
Reminder to Students
-
Always wear safety equipment.
-
Handle tools properly.
-
Keep the work area clean.
-
Follow instructions carefully.
Teacher’s Reflection
After the lesson, the teacher should reflect on:
-
Did the students understand the lesson clearly?
-
Were the students able to perform the tasks properly?
-
What teaching strategies were effective?
-
What improvements can be made in the next lesson?
References
-
Automotive Technology Modules
-
Senior High School TVL Curriculum