Maintenance: Diagnosing Machine Malfunctions is one of 9 topics in the Grade 11 Mechanical Technology CAPS syllabus, covered across 3 lessons on Study Vault. Below are real practice questions from this topic with full worked answers.
Sample practice questions
Easy
1. What is the direct symptom of a lack of lubrication between moving machine surfaces?
Increased friction, generating excess heat and accelerated wear
Reduced friction and cooler operation
No effect on the machine at all
Improved smoothness of operation
Answer: Increased friction, generating excess heat and accelerated wear — A lack of lubrication causes moving surfaces to rub directly against each other, generating increased friction, excess heat and accelerated wear.
Easy
2. What is meant by "incorrect lubrication" as distinct from a lack of lubrication?
Using a lubricant of the wrong type, such as one with unsuitable viscosity, even though lubricant is present
Using exactly the correct lubricant specified for the machine
Applying too much of the correct lubricant
Never applying any lubricant at all
Answer: Using a lubricant of the wrong type, such as one with unsuitable viscosity, even though lubricant is present — Incorrect lubrication means using a lubricant of the wrong type for the application, such as unsuitable viscosity or a lubricant not rated for the operating temperature, even though some lubricant is technically present.
Medium
3. Name a characteristic audible symptom that can indicate a lubrication-related fault during machine operation.
Answer: grinding or squealing sound — A grinding or squealing sound during operation is a characteristic symptom that can indicate a lubrication-related fault, alongside unusual heat and visible wear marks.
