In a perfect environment your  vehicles engine works very hard to maintain a desired operating temperature.

When I was 18 years old still an apprentice I will never forget the time I was looking at my sisters car, it was over heating so I thought I would investigate this problem.

I was about to remove the radiator cap with full knowledge that most radiators caps have a release notch when removing the cap to prevent the pressure of the cooling system spraying hot water every where.

Well I was rotating the cap to release the pressure with the understanding that there was no pressure under the cap, next thing I was overcome by extreme hot water onto my face, this was embarrassing the next thing I remember I was on my way to the Dandenong Hospital, with burns to the face and eyes, this is why its very important to understand the dangers of opening a radiator cap when the engine is hot especially when or if the cooling system is over heating.

The only time to remove a radiator cap is when the engine is cold.

An engine thermostat should never be removed accept when replacing a faulty thermostat, for some reason many people think if they are having a problem with high engine temperature a solution is to remove the thermostat.

The misconception is by removing the thermostat the gauge may decrease from high to normal.

Allow me to explain what happens if a thermostat is removed form an engines cooling system; the water is not transferring hot water from the engine to the radiator as its designed.

The purpose of the thermostat is to hold water in the engine long enough for the molecules to expand then the thermostat will open and allow the hot water into the radiator to cool down and contract, this is in normal operating conditions.

Let me add if the cooling system requires constant topping up this means there is a leak in the cooling system and the potential of rapid cooling and rapid heating, this is where the cylinder head will be exposed to a higher heat range and thus offering the potential warping and or cracks.

The cooling system is designed to maintain a constant desired engine temperature to aid in the ultimate fuel economy as the air to fuel ratio only operates effectively when the engine is operating within this parameter.
Written by Darren Gow-Brown Virtualmechanic.com.au

Virtualmechanic Darren Gow-Brown free online video is explaining checking the tyre pressure is vital to prevent breaking down on the side of the road

Caution never check the radiator when hot or risk severe burns to your body

Use caution when performing this task, do not remove plugs when the engine is hot