Valves are among the most critical components of the internal combustion engine. But what exactly are they? And how can you maintain them properly?

What Are Engine Valves in a Car?

• Valves are metal components with a conical shape, installed in the engine head. They move in a reciprocating (up and down) motion to open and close the pathways for fuel intake and exhaust release.
• Their proper function is essential for sealing and unsealing these passages during engine operation.

How Do Engine Valves Work?

• Intake Phase: The intake valves open to allow the air-fuel mixture to enter the combustion chamber.
• Compression Phase: All valves close to compress the mixture before ignition.
• Power Phase: The spark plug ignites the mixture, pushing the piston downward.
• Exhaust Phase: Exhaust valves open to expel burnt gases from the combustion chamber.

How Many Valves Does an Engine Have?

• Older Engines: Typically have two valves per cylinder (e.g., a 4-cylinder engine = 8 valves).
• Modern Engines: Commonly feature four valves per cylinder (two intake and two exhaust). Some sports cars may even have five valves per cylinder.

What Is Variable Valve Timing (VVT)?

This technology enhances engine performance by intelligently controlling the timing of valve opening and closing. It helps to:

• Improve fuel efficiency
• Increase torque and reduce emissions
• Minimize engine noise

Symptoms of Faulty Valves in a Car

• Knocking or ticking sounds from the engine, especially at higher RPMs
• Loss of engine power due to poor compression
• Blue smoke from the exhaust (a sign of oil leaking into the combustion chamber)
• Excessive oil consumption without a clear cause
• Engine shaking during idle or startup
• Popping sounds from the exhaust due to incomplete combustion

Tips to Maintain Your Engine Valves

To avoid valve damage and ensure their longevity, follow these tips:

• Change engine oil regularly to maintain lubrication and prevent valve seal wear.
• Use high-quality oil recommended by the vehicle manufacturer.
• Avoid prolonged high-speed driving which can stress the valves.
• Inspect spark plugs regularly, as faulty plugs affect combustion and valve performance.
• Watch for unusual exhaust colors (like blue smoke) and consult a mechanic promptly.
• Perform regular cooling system maintenance, as overheating can lead to valve damage.

What Is Radiator Coolant?

Radiator coolant, also known as antifreeze, is a chemical compound used to regulate engine temperature. Its primary function is to prevent the engine from overheating in hot conditions or freezing in cold ones, protecting internal components from corrosion and damage.

Coolant is typically made from ethylene glycol or propylene glycol, with added corrosion inhibitors and thermal stabilizers.

Types of Radiator Coolant and Their Differences

Coolants used in radiator systems fall into three main categories, each with distinct properties that directly affect engine performance and efficiency:

1. Regular Water

Although easily accessible, using plain water in the cooling system is unsafe. It contains high levels of salts and impurities that accumulate inside the radiator and engine components, causing corrosion, rust, and long-term damage.

Water also boils quickly and freezes easily, making it unsuitable for temperature fluctuations.

2. Green Coolant

Green coolant is a balanced mixture of water and specially formulated chemicals designed to cool the engine efficiently without reacting with its metal components. Key features include:

- Free from salts and impurities, preventing corrosion and rust

- Boiling point raised to 120°C, making it effective in high-temperature conditions

- Safe and effective, though its lifespan is shorter than other types

3. Red Coolant

Red coolant shares the impurity-free nature of green coolant but offers enhanced features:

- Contains agents that prevent freezing in extremely low temperatures

- Free from silicates, which can cause long-term corrosion in engine parts

- Used in modern vehicles requiring extra protection for sensitive metal components

- Longer lifespan than green coolant, ideal for cold climates

Causes of Coolant Boiling in the Radiator

Boiling coolant is a serious warning sign of a malfunctioning cooling system. Ignoring it can damage vital car components. Common causes include:

• Faulty Thermostat: Regulates coolant flow between the radiator and engine. If it fails, the engine doesn’t receive adequate cooling, leading to overheating and boiling.
• Cooling Fan Failure: The fan plays a crucial role in cooling the radiator. If it stops or underperforms, engine temperature rises, causing the coolant to boil.
• Damaged Radiator Cap: Should be replaced every two years. A worn or loose cap affects system pressure and reduces the radiator’s ability to maintain proper temperature, contributing to boiling.

Causes of Coolant Loss in the Radiator

All coolant types can decrease over time due to mechanical or operational issues affecting system efficiency. Key causes include:

• Faulty Thermostat: Disrupts temperature regulation, leading to coolant loss
• Cooling Fan Malfunction: Reduces radiator cooling, increasing coolant consumption
• Water Pump Failure: Responsible for circulating coolant to the engine; any damage causes noticeable fluid loss
• Leaks or Cracks: In radiator pipes or the reservoir tank, leading to gradual coolant reduction
• Heavy A/C Usage: Prolonged use increases pressure on the cooling system, accelerating coolant consumption

When Should You Change Your Coolant?

Coolant replacement depends on its type and chemical composition:

- Red Coolant: Recommended every 4 to 5 years due to its long-lasting organic formula

- Green Coolant: Should be replaced every 2 to 3 years, as its protective agents degrade over time

What’s the difference between green and red coolant?

Green contains silicates and has a shorter lifespan; red is silicate-free and lasts longer.

Can you mix coolant colors?

No. Chemical reactions between types can damage the cooling system.