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How Much does a Head Gasket Replacement Cost?
The engine assembly in a modern motor vehicle can be split up into two major components – the cylinder head and the engine block.
The cylinder head houses the valvetrain components, such as the camshaft/s and fuel injectors, and the engine block houses the rotating assembly of the crankshaft and pistons as well as other crucial cooling and lubricating components.
Both these components rely on oil and coolant to provide lubrication and cooling properties as well as a good seal between them to allow proper compression inside the cylinders.
All these components need to be separated otherwise engine failure will result. Enter, the Head Gasket!
The job of the Head Gasket is to join the cylinder head to the engine block to provide a sealed area for combustion to occur, as well as allow the coolant and oil to circulate to the sensitive components that need it most without them becoming contaminated.
All this stress placed on the gasket can cause it to fail or ‘blow out’ over time or when the engine is overheated – it is designed to fail first to prevent further damage to other components, but operating a vehicle with a blown head gasket may cause complete engine failure.
The average price of a head gasket replacement starts around $1200 and can increase to $3000+ depending on any other damage and other work required. An inspection by a mechanic will confirm the costs for you.
Head Gasket Replacement
What is a Head Gasket?
The head gasket is the most important gasket in the engine. It sits between the cylinder head and engine block and its purpose is to create a seal around the cylinders to allow for maximum compression inside the cylinders and to prevent coolant entering the combustion chamber.
They are usually made of a composite material, but can also be made of copper or a multi steel layer design to provide the best possible seal.
When the cylinder head is bolted down to the engine block, it compresses the head gasket to create an airtight seal between the two, while small cutouts in the gasket allow coolant and oil to flow through to the top of the engine.
Symptoms of a Head Gasket Failure
- Engine overheating
- Engine running poorly, or misfiring
- Excessive white steam from the exhaust when engine running
- Milky oil due to coolant contamination – looks like chocolate milk
- Exhaust gases in the cooling system when engine is running
How is the repair performed?
- The head gasket will be confirmed as the failed component
- The engine oil and coolant will be drained from the engine
- The cylinder head and all associated components will be removed from the engine and sent away to be inspected and cleaned
- The old head gasket will be removed and the engine block will be checked for damage
- The new head gasket will be fitted to the engine, and sealant will be applied as required
- The cylinder head and associated components will be refitted and torqued to the correct specifications
- The engine will be filled with new coolant and oil and the engine run to check for any leaks
- The vehicle will be road tested to ensure correct operation
Tips to Remember
- Around 70% of the repair cost will be labour, as replacing the head gasket on many vehicles is a very labour intensive task, sometimes taking 10 hours or more to carry out the job correctly.
- Before assuming the worst, make sure your vehicle is inspected to correctly diagnose the issue you are having, to prevent expensive repairs that don’t fix the problem!
How Important is this Repair?
Operating your vehicle with a blown head gasket not only increases the chances of causing irreparable engine damage but may leave you stranded on the side of the road waiting for a tow truck to come and pick you up.
If you notice the temperature gauge moving towards that red ‘H’ or white smoke coming from the exhaust, it’s time to have your vehicle inspected and repaired before it’s too late!
If you’ve read this far, you obviously care about your car. A lot. So next time you need a service, repair or inspection, visit AutoGuru.com.au. We let you search and book from over 1600 qualified mechanics, who eat car troubles for breakfast.