United Garage Services

How to keep your car cool to avoid a blown cylinder head gasket...

by Approved Garages | 17 Apr 2019

Blowing a cylinder head gasket isn’t a rare problem with cars these days, but they are easily avoidable. Blown head gaskets can be prevented with regular car check-ups.

It’s all about keeping cool under pressure. And, that’s good advice for both the car and its driver.

What is the function of a cylinder head gasket?

The cylinder head gasket stoppers the combustion chamber of your engine block to stop hot exhaust gases from escaping and oil or coolant from entering. But, because combustion gasses run so much hotter than oil or coolant, the temperature fluctuations can cause that seal to damage over time. This can happen earlier if the coolant level is low and such conditions are cooperated, which can limit the cooling system’s efficiency.

When did you last check your coolant level?

Coolant is the true essence of your engine. It aids the engine maintain proper temperature to avoid overheating. Low coolant levels or unkempt/dirty coolant are common causes of a blown cylinder head gasket. Many drivers don’t do engine coolant check-ups. Typically, drivers only think to do engine coolant check-ups twice per year—before winter and summer.

It is wiser to check your coolant each time you open the hood, not just seasonally. Coolant levels have little do with outside temperature of the car, and everything to do with your engine’s internal temperatures.

Check your coolant levels.

Vehicle manufacturers have made it very easy to check your coolant level in your vehicle. Just open the car bonnet and take a looka t the expansion coolant reservoir. If the coolant is at the “full” line, you’re good to go. If not, make sure to top it off with a compatible coolant. Now, if the coolant level is low in your radiator tank but full in your overflow tank, that might signify an even more troubling diagnosis. In that case, we recommend a professional check-up of your vehicle.

To find your nearest Approved Garage to check your coolant for you, head over to our homepage and put your postcode into the search bar to find local garages in your area.

Test the state of your coolant

Engine systems are intended for a 50/50 combination of water and reserved glycol. If that mix is off, it will increase the temperature, your engine will burn, and your coolant will start boiling off.

When the coolant level gets too low, air pockets form in the cooling system. This can decrease its own efficiency to cool and correctly control functioning temperatures of your vehicle. If that happens, the cylinder head gasket can be compromised and then, well, the head gasket can blow. We would advise that you ask a trained mechanic to check the state of your coolant for you, unless you feel confident doing it yourself and have the proper tools to check.

If you want to test the mixture ratio of your coolant yourself, you will need a handheld antifreeze tester. This is a simple tool that uses a rubber suction bulb to draw a slight amount of coolant into a test chamber containing a floating gauge. You must check your coolant condition safely when the engine is cold.


If you are uncertainty, check the upper radiator pipe. If it is too hot to touch or if it is under pressure (difficult to squeeze) do not open the radiator cap. Once you have found that the cooling system is not under pressure, it is safe to remove pressure cap and test the coolant in your expansion coolant reservoir. Read the directions on your tester for specific testing instructions. The tester will help you to make visual observation on your coolant condition. Once you know the makeup of your coolant, you can adjust as necessary. We recommend using distilled water to dilute the amount of coolant in the system. When raising the ratio of coolant in the system, use a full-strength coolant.

 Flush and Refill the engine coolant

If your coolant is in bad condition (no colour, presence of the rust, oil, strong odour, and/or particles), we recommend doing a full flush. Flushing the cooling system removes any junk that may be impeding the flow of coolant through the system. It also refreshes the additives which help prevent corrosion and protect important cooling system components like the water pump, radiator, heater core, thermostat and other parts of your engine. When refilling the system refer to your vehicle owner’s manual for the correct coolant mixture ratio to suit your vehicle manufacturers recommendations. Make sure to properly capture and dispose of any used coolant in accordance with regulations.

Flushing a cooling system can be messy, so you may want to defer to your trusted local repair garage. They will also be able to properly dispose of your used coolant correctly, saving you the hassle.

Don't blow the cylinder head gasket...Keep cool and ride on.

Find your nearest Approved Garage to do a cylinder head gasket and coolant level and quality inspection. Click here to find your nearest garage.