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What happens when your head gasket is replaced

Ellie Dyer-Brown, 11 months ago

5 min read

  • Advice
  • Repair
Head Gasket

There are a number of signs which give away the fact that the head gasket in your car is going to break. To find out what they are, read on!

Head gasket repairs can be extremely expensive and difficult to resolve, and few of us know what actually happens when your head gasket is replaced. However, if you catch a problem early, you might not have to pay a huge fee for a replacement.

If the head gasket in your car engine explodes, your entire engine might be completely written off so it is vital that you are able to detect and resolve the problem before that happens!


What is a head gasket and what does it do?

The head gasket is responsible for sealing pressure within a car engine as well as the distribution of oil and engine coolant.

Every time you turn on your engine the head gasket has to operate within very high temperatures and pressures, which is exactly what it is designed to do.

The engine of your car needs to be cooled constantly as it relies on combustion for power and the head gasket is the core component in performing this job.


Damaged head gasket

If the head gasket is damaged, the engine will quickly overheat and serious damage will be caused. Overheating in the engine of your car will lead to a loss of compression, the mixing of oil, water, coolant as well as a reduction in lubrication.

The head gasket is a very complex piece of equipment and so a variety of materials are needed to build it. It must be able to withstand and function normally at extreme temperatures and pressure. It also needs to be resistant to all of the chemicals and oils which rush around your car engine.

As a result, each gasket from one car to the next is different as the demands of each engine are unique. Car manufacturers like Ford, Vauxhall and BMW spend millions of pounds every year in the research and development of head gaskets to help manage the pressure and cooling of engines.

Replace a damaged head gasket


Signs of a faulty head gasket

Most drivers know what a head gasket is, but many are unsure what causes a blown head gasket. Fortunately, there are a few blown head gasket symptoms you can look for to find out whether yours needs repair. Meaning you can have any problems seen to before it develops into a serious issue.

  • The temperature gauge is higher than normal

  • You can see bubbles rising once the cap has been removed from the car radiator

  • Your car is chugging or suffers from a loss of power

  • There is engine coolant or oil on your spark plugs

  • Your engine oil is thicker than usual – You can check by using a dipstick

  • A lot of white smoke is being emitted from the exhaust or liquid is dripping from the same place

Head gasket diagnostic services


What Actually Happens When Your Head Gasket is Replaced?

Accessing the gasket can be quite a lengthy procedure as it involves removing a large set of engine components. The exact process for head gasket removal varies depending on your car model. The full details of which you can typically find in your car’s service manual.

To gain access to the gasket the battery and engine is removed, with the engine oil and coolant also drained.

The old gasket, once reachable, is often removed with a pry bar. The area underneath where the old gasket sat is then thoroughly cleaned, creating a solid seal for the new one.

At this point the area is inspected for damage. If all looks good it is time for the new gasket to be inserted.

The new gasket is placed on the head to ensure a tight seal. A head gasket sealer is sometimes used at this stage to close any gaps.

The next stage involves re-fixing all the head bolts and to put the remainder of the engine back together.


Once more, if you notice any of these issues, find a local mechanic as quickly as possible using WhoCanFixMyCar. You can get a range of bespoke quotes from the best garages near you for free.

Enter your registration number and a few contact details, to receive direct estimates of head gasket repair cost from local mechanics:

Get Quotes For Head Gasket Repairs


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