Banner showing a car being filled up with coolant

How to refill coolant

Your engine is the beating heart of your car. Harnessing energy to keep you moving causes the temperatures to rise inside your engine and if it’s not properly cooled, you risk the engine overheating and potentially seizing should the metal parts fuse together. It only takes a couple of minutes to check your coolant levels and refill if necessary. 
Banner showing person checking coolant

When should you check your coolant?

No matter what the weather is outside, you need to keep an eye on your car coolant levels to prevent overheating and protect your engine. You should check your coolant levels at least twice a year. It’s recommended you do this before summer and again before winter so you’re aware of your levels before any extreme weather changes occur.

How to check and refill your coolant: step-by-step

Guide on how to check and refill your coolant 1. Wait 10 mins from last use 2. Open bonnet 3. Find coolant reservoir 4. Find minimum/maximum marks 5. Check coolant level 6. Check dilution instructions 7. Wait 3 hours, remove cap bit by bit 8. Slowly add coolant 9. Replace cap and close bonnet

If you are going to refill your coolant, you’ll need to wait at least three hours to give your engine a chance to cool and make sure no pressurised water escapes when you remove the coolant cap (as this could burn you). 

  1. Park your car on a flat surface, and make sure you wait at least ten minutes from the last use to give the engine a chance to cool.

  2. Open up your bonnet and secure it safely.

  3. Find your coolant reservoir. If you’re not sure where this is, your vehicle’s handbook should help you locate it

  4. Look for the minimum and maximum marks on the side of your coolant reservoir tub.

  5. Your coolant level should be in-between these marks. If it’s below or near the minimum mark, then you’ll need to top-up. 

  6. To refill coolant, first you’ll need to know if you’re using the coolant as is or if you need to dilute the solution with distilled water. Follow the instructions on your Mobil coolant for this. 

  7. Remove the cap from the coolant reservoir slowly bit by bit, letting the pressure release while you keep your distance slightly (remember your engine needs to have not been in use for at least three hours before doing this part).

  8. Using a funnel slowly pour in the correct coolant for your car until it reaches the cold fill line. The funnel is to help avoid any spilling on your hands or the ground.

  9. Twist the cap back onto the coolant reservoir until it clicks into place and then close your bonnet.
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