How do I know if my coolant needs topping up?

If your vehicle's coolant level is low, it's important to top it up to ensure your engine stays properly cooled and protected. But how can you tell if your coolant needs a refill? This article will provide a detailed guide on the signs to look for and steps to take to check and top up your coolant as needed.

Signs Your Coolant Needs Topping Up

There are a few key indicators that your vehicle's coolant level may be low and in need of a top-up:

• Low coolant level in the overflow tank or radiator - Visually inspect the coolant level in the overflow tank or radiator. If it's significantly below the full mark, you likely need to add more coolant.


• Engine running hotter than normal - If your temperature gauge is reading higher than usual, it could mean the coolant level is low and the engine is not being properly cooled.


• Visible leaks - Check for any coolant leaks around the radiator, hoses, or other engine components. Drips or puddles of coolant are a clear sign the level needs to be topped up.


• Overheating warning light - If your vehicle's dashboard displays an overheating or high temperature warning light, that's an immediate indication the coolant level is low and needs attention.

If you notice any of these signs, it's best to check the coolant level as soon as possible and top it up if needed to prevent further damage to your engine.

How to Check and Top Up Coolant

Checking and topping up your vehicle's coolant is a relatively simple process:

1. Locate the coolant overflow tank or radiator - This is typically located near the front of the engine, often on the driver's side.


2. Inspect the coolant level - Look at the coolant level in the overflow tank or radiator. It should be between the "Min" and "Max" or "Low" and "Full" markings.


3. Add coolant if needed - If the level is low, carefully remove the overflow tank cap (or radiator cap if no overflow tank is present) and add the appropriate coolant type until the level reaches the full mark.


4. Check for leaks - After topping up the coolant, inspect the area for any new leaks that may have been caused by the refilling process.


5. Replace the cap securely - Make sure to replace the overflow tank or radiator cap tightly to prevent any coolant loss.

Be sure to use the correct type of coolant recommended for your vehicle, as mixing different coolant formulas can cause issues. If you're unsure, consult your owner's manual or speak with a mechanic.

Regularly checking and maintaining your vehicle's coolant level is an important part of proper engine care and can help prevent costly repairs down the road. By being vigilant for the signs of low coolant and taking the necessary steps to top it up, you can keep your car running smoothly and efficiently.

How do I know if I need to top up my coolant?

Signs Your Coolant Needs Attention

1. Low coolant in the reservoir. If your vehicle has a coolant reservoir, the level should be between the ADD and FULL marks.
2. Higher than normal temperatures.
3. A puddle under the vehicle.
4. Floating debris in the coolant.
5. It isn't strong enough.
6. Oil in the coolant.

How often do I need to refill coolant?

You should check your coolant level at least once a month, and you should only need to add coolant if the level is low, which should be rare in a healthy system. If you find yourself adding coolant frequently, it indicates a possible leak that needs professional inspection to prevent engine damage. 
When to check the coolant level

• Check at least once a month, or every other time you fill up with gas, especially for newer cars. 
• For older or higher-mileage cars, checking every time you get gas is a good practice. 
• Always check when the engine is completely cold to avoid burns from hot coolant. 

When to add coolant

• Add coolant only if the level is at or below the "Low" or "Min" mark on the reservoir. 
• If the engine is hot, wait for it to cool down for at least 30-60 minutes before adding coolant. 
• Use the correct type of coolant for your vehicle, as specified in your owner's manual. 

When to worry and seek professional help

• If you have to add coolant frequently, it's a sign of a leak. 
• Constant coolant loss can be caused by issues like a faulty water pump, a cracked hose, a bad head gasket, or a radiator problem. 
• If you notice any of these signs, get your cooling system inspected by a professional to avoid serious engine damage. 

Can I refill my coolant myself?

Yes, you can refill your coolant yourself, but it's crucial to do it safely by making sure the engine is completely cool first to avoid burns. You will need to identify the correct type of coolant for your car, add it to the correct reservoir (either the radiator or the expansion tank) up to the fill line, and check for leaks or low levels over the next few drives, as a persistently low level could indicate a leak elsewhere in the system. 
Before you begin

• Ensure the engine is cool: Never open the radiator or coolant cap when the engine is hot, as the system is under pressure and can cause serious burns. 
• Gather supplies: You will need the correct type of coolant for your vehicle (check your owner's manual), distilled water (if mixing a concentrate), a funnel, rags, and work gloves. 
• Identify the coolant type: Check your owner's manual to determine the exact type of coolant your car needs, as mixing different types can be harmful. 

This video demonstrates how to safely check and add coolant to your car's cooling system: 1m2CarProsYouTube · Oct 6, 2016
How to add coolant

1. Locate the fill point: Find the coolant reservoir, which is usually a clear plastic tank with "min" and "max" or "cold" and "hot" lines on it. Some older systems may require adding coolant directly to the radiator cap. 
2. Open the cap slowly: Slowly unscrew the cap to release any residual pressure. 
3. Add the coolant: Fill the reservoir to the "cold" fill line. If your coolant is concentrated, you'll need to mix it with distilled water in the ratio recommended in your owner's manual (usually 50/50). Do not fill above the "max" line, as the coolant will expand when the engine heats up. 
4. Replace the cap: Securely replace the cap. 
5. Monitor the level: After running the engine for a while, check the level again. It may drop as the thermostat opens and coolant fills the system. If it drops again, add more coolant as needed and continue to monitor for a while to ensure the level is stable. 

What to do if the level keeps dropping

• If you have to add coolant frequently, there is likely a leak in the system. 
• A mechanic can perform a pressure test to find and fix leaks, which could be from hoses, the radiator, the water pump, or even a head gasket. 

What are the symptoms of low coolant?

Symptoms of low coolant include a dashboard warning light, a rising temperature gauge, and a poorly working heater. You may also notice a sweet smell, a visible coolant leak under your car, or steam from the engine. 
Warning indicators

• Dashboard warning light: A dedicated low coolant light or the "check engine" light may illuminate. 
• Rising temperature gauge: The temperature gauge will move toward the red "hot" zone. 
• Poor cabin heating: The heater may only blow cold air because there isn't enough coolant to heat the air in the cabin. 

Visual and auditory signs 

• Steam from the engine: You might see steam coming from under the hood, especially when the engine is hot. 
• Visible coolant leak: A puddle of colored fluid (often green, pink, or orange) under your car after it has been parked is a strong sign of a leak. 
• Bubbling sounds: You may hear bubbling sounds from the engine. 

Other signs

• Sweet smell: A sweet, chemical odor can indicate a coolant leak. 
• Engine performance issues: Low coolant can cause poor acceleration, rough idling, or engine misfires. 
• Reduced gas mileage: The engine may become less efficient if it's not cooling properly. 

If you notice any of these signs, it is important to have your vehicle checked by a professional to prevent severe engine damage.