How to Check and Top-Up Your Coolant - Super DIYs, by Supercheap Auto on YouTube. 2 min 18 s.
- Video length
- 2 min 18 s
- Time to do it
- 10 minutes
- Difficulty
- Easy
- Steps
- 8
What you need
Steps
Park on flat ground and let the engine cool completely, at least 30 minutes after a drive. Never open a coolant cap while the engine is hot.
Open the bonnet and find the coolant reservoir. It is a translucent plastic tank near the front of the engine bay, usually marked with a radiator symbol and MIN and MAX lines.
Check the level through the plastic against the MIN and MAX marks. With a cold engine it should sit between the two, closer to MAX.
If the level is at or below MIN, look up the coolant spec in your owner's manual. Buy a pre-mixed bottle, or a concentrate you dilute to the ratio printed on the label.
Put a funnel in the reservoir and pour coolant in slowly until it reaches the MAX mark. Stop there, because coolant expands as it heats up.
Refit the cap firmly and wipe up any spills. Coolant is slippery and toxic to pets, so rinse the area with water afterwards.
Start the engine and let it idle for a few minutes with the heater set to hot. Watch the temperature gauge and look for drips or a sweet smell.
Let the engine cool again and recheck the level. Top up to MAX if it has dropped, then check it again in a week.
Tips and common mistakes
Only check and top up when the engine is cold, because a hot system is pressurised and can spray boiling coolant.
Do not use tap water as a long-term top-up; it dilutes the antifreeze and reduces corrosion protection.
Do not mix different coolant types, such as a green conventional coolant and an orange OAT coolant, since they can gel and block the system.
If the level keeps dropping, get the system pressure tested, as a slow leak will not fix itself.
Questions
Can I just top up the coolant with water?
Plain water will get you home in an emergency, but swap it for the correct coolant as soon as you can. Too much water weakens the antifreeze and corrosion protection.
How do I know which coolant my car needs?
Check the owner's manual or the specification printed on the coolant bottle. Colours vary between brands, so match the specification rather than the colour.
How often should I check the coolant?
Check it once a month with a cold engine and before long trips. Your service book lists how often the coolant should be fully changed.
This guide was drafted from the video's details and general task knowledge. It has not been checked against the full video. Check the video and relevant product instructions before following a procedure. Report a correction.
