How to check coolant level

The right level of anti-freeze or coolant during the summer months is critical for the health of an engine. Modern cars run with high operating temperatures and high pressures but don’t need a lot of coolant. But coolant is critical as you’ll see in the follow section where we tell you how to check the coolant level.

Operating temperatures

The heat generated by the car is dissipated in several ways. You might be surprised to read that only 28% of the heat generated by the internal combustion engine is actually available to power the car. Around 7% of the thermal energy the car produces is lost as a result of friction through the engine and the tyres among other things. Close to 35% disappears through the exhaust which leaves us with 30%. That remaining percentage is dealt with by the coolant. If there’s no coolant in the block, the engine could go into meltdown.

How to check the coolant levels

This is the same operation in all cars. It’s pretty simple so there’s no excuse to not check this pretty regularly. The most important advice is to not remove the radiator cap when the engine’s hot. The water released could easily scald you if you try this. In most cars the reservoir tank for the coolant is clear, although some years of use will darken it. You’ll see MIN and MAX marks on the side which obviously indicate the levels of coolant the tank can accept. Fill to maximum and replace the cap.


If the reservoir tank is empty, you’ll need to check the coolant levels in the radiator. You’ll see a screw cap on top of the radiator that’s marked as the radiator filler cap. Unscrew and then fill with undiluted coolant up to the filler opening. You should also fill the reservoir tank to the MAX level when the radiator’s replenished.

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