What is the primary function of oil in an engine?

• To increase friction

• To provide lubrication

• To add weight

• To change colour

What happens to metal surfaces when viewed under a high-powered microscope?

• They appear smoother

• They appear coarser

• They appear transparent

• They appear reflective

What is the main difference between full-fluid film lubrication and boundary lubrication?

• Full-fluid film lubrication uses water, boundary lubrication uses oil

• Full-fluid film lubrication occurs under pressure, boundary lubrication occurs with splashing or misting

• Full-fluid film lubrication is for small engines, boundary lubrication is for large engines

• Full-fluid film lubrication is noisier than boundary lubrication

What could happen if the lubricant film breaks down in an engine?

• The engine will become quieter

• The engine could overheat and seize

• The engine will run faster

• The engine will produce more power

How does oil help in cooling an engine?

• By absorbing and carrying away heat from moving parts

• By increasing the engine's temperature

• By reflecting sunlight

• By reducing the engine's size

What role does oil play in cleaning an engine?

• It adds dirt to the engine

• It removes carbon particles and impurities

• It changes the engine's colour

• It increases the engine's weight

What is the function of detergent oils in modern engines?

• To increase sludge build-up

• To keep particles in suspension and reduce sludge build-up

• To make the oil thicker

• To change the oil's colour

How does oil act as a cylinder seal?

• By increasing the gap between piston rings and cylinder walls

• By providing a seal between piston rings and cylinder walls

• By removing the seal between piston rings and cylinder walls

• By changing the shape of the cylinder

How does oil help in deadening sound in an engine?

• By increasing metal-to-metal contact

• By preventing metal-to-metal contact and coating components

• By amplifying engine noise

• By changing the engine's shape

What is the role of penetrating oils?

• To increase corrosion

• To free seized parts and repel damp

• To make the engine heavier

• To change the engine's colour