United Garage Services

Antifreeze, coolant and protecting your engine from extreme temperatures

by Approved Garages | 13 Nov 2019

Winter is coming, so if you’re all about being prepared for the coldest time of the year, you’re going to want to make sure your vehicle’s engine stays working during freezing conditions.

That’s where antifreeze comes in handy, but what is it and what happens to your car if you forget it?

What is antifreeze and why is it important?

Antifreeze is a liquid you add to the water in an engine’s cooling system. This is essentially what forms the ‘coolant’ solution in your engine, which is one of the most crucial fluids under your vehicles bonnet, maintaining the temperature of the engine to prevent overheating and freezing.

What happens to your coolant fluid without antifreeze?

Made from either ethylene glycol or propylene glycol, antifreeze changes the freezing and boiling points of water. Without antifreeze, the fluid in your coolant tank is pretty much just water, and what happens to water in freezing temperatures? It freezes of course! And you won’t get far with a frozen engine.

And what happens to an engine with no coolant?

Coolant/antifreeze needs to circulate through the engine to maintain the correct working temperature of different components and protect them from heat, freezing and corrosion. If your car runs out of coolant on the road, it will result in one of the following:

    1. Auto engine cut-off – Most modern vehicles are fitted with an automatic engine cut-off sensor. This is designed to prevent damage when the engine starts to heat up due to lack of coolant fluid


  1. Damage to engine parts – If your car doesn’t have a cut-off feature and you continue driving, you’ll begin to harm parts of the engine which could result in permanent and irreparable damage to your vehicle

The resulting damage is likely to include:

  • Warped or bent connector rods
  • Crank failure
  • Cylinder and piston timing being off
  • Cylinder head damage
  • Damage to the water pump
  • Head gasket damage

Signs of seriously low or no coolant

When it comes to the warning signs of dangerously low coolant/antifreeze levels, there are quite a few to look out for. You’ll be able to spot the following signs straight away, and if you do you should get those fluid levels topped up immediately:

  • Dashboard warning light or abnormal temperature gauge
  • billowing steam from under bonnet
  • an extremely hot bonnet
  • no control over the interior heating system

If you notice any of these, find a safe place to pull over immediately to try and prevent further damage to your vehicle.

Our recommendation

Of course, we recommend you keep your coolant/antifreeze levels topped up at all times, making sure you have spare fluid stored in your vehicle just incase.

If you have driven your vehicle with no coolant in the tank at any point, take your vehicle to an approved garage right away - especially if you’ve noticed any of the signs we mentioned above.