Coolant (antifreeze) carries heat away from your engine and stops corrosion inside it. In Nairobi traffic and on hot upcountry climbs, a cooling system that's even slightly low can tip an engine into overheating, and overheating is one of the fastest ways to cause serious engine damage. Checking the level takes a minute, but it must be done on a cold engine.
You'll need
- The coolant type your manual specifies (ready-mixed, or concentrate plus distilled water)
- A cloth and a funnel
⚠ Safety first
- Never open the coolant cap or the radiator cap on a hot or warm engine. The system is under pressure, and scalding coolant can spray out. Wait until the engine is completely cold — ideally a few hours after driving.
- Coolant is poisonous and tastes sweet, which attracts children and pets. Wipe up any spills and store it out of reach.
Step by step
- 1
Park level and let the engine cool fully
Check before your first drive of the day, or wait several hours after driving. Touch the top of the radiator hose — if it's warm, wait longer.
- 2
Find the expansion tank
Open the bonnet and look for a translucent plastic tank, often near the radiator or on one side of the engine bay, with a cap that usually carries a warning symbol. Don't confuse it with the windscreen washer bottle (a larger tank with a windscreen symbol) or the brake-fluid reservoir (a small tank near the driver's side bulkhead).
- 3
Read the level
You can usually see the coolant through the side of the tank. It should sit between the MIN and MAX (or LOW and FULL) marks when cold. Wipe away dust if you can't see it clearly.
- 4
Open the cap slowly (cold engine only)
If you need to top up, cover the cap with a cloth and turn it slowly, a quarter-turn at first, to release any remaining pressure. Then remove it.
- 5
Top up with the right coolant
Pour in the coolant your manual specifies until the level reaches the MAX mark — no higher. If you're using concentrate, mix it with distilled or deionised water in the ratio on the bottle (usually 50/50). Avoid tap water: minerals in hard water leave deposits in the cooling system.
- 6
Refit the cap and check for leaks
Screw the cap back on firmly until it clicks or seats. Glance around the hoses, radiator and under the car for drips. Wipe up any spills.
Pro tips
- Don't mix coolant types without checking the manual. Different chemistries (and colours) aren't always compatible, and mixing them can form sludge.
- In a genuine emergency, clean water will get you home. Then have the system drained and refilled with the correct mix, because water alone gives no corrosion protection.
- A level that keeps dropping means there's a leak somewhere — hoses, radiator, water pump or head gasket. Topping up is a temporary fix, not a cure.
- Coolant wears out. Most manufacturers specify a change every 2–5 years; your service schedule says when.
Stop and get a mechanic if…
- The temperature gauge climbs towards red, or a red temperature warning light comes on — pull over safely, switch off, and let it cool. Don't open the cap.
- White, sweet-smelling steam from the exhaust or under the bonnet.
- You need to top up more than once a month.
General guidance only. Your owner's manual has the final word on specs, fluids and procedures for your vehicle. Last reviewed 24 September 2026.