In general, there are a few signs that will point to head gasket failure. If engine oil and coolant are found mixed together, either in the engine or in the cooling system, the gasket is often the culprit.
Further testing will be done, and a machine shop will try to confirm whether the head gasket is the problem.
How is a head gasket replaced?
Replacing a head gasket is a labor-intensive process and requires disassembly of several under-hood parts before even reaching the engine. Then, parts of the engine will be taken apart in order to inspect and clean the areas touching the head gasket, and to replace the failed gasket. Then everything must be put back together. This process will take several days, typically.
If any of the removed components are found to be worn or failing, it may be best to replace them at this time, as well.
RepairPal recommendations for head gasket issues
If many components are recommended for replacement, or an engine rebuild or replacement is necessary, consider the cost of rebuilding versus getting a new car.
Additives that claim to stop leaks or reseal the head gasket from the engine coolant passages are dangerous. They can clog the radiator or damage the water pump.
Can I replace the head gasket myself?
This is not a DIY project. There's a lot of disassembly to be done, and many factors to consider while repairing a head gasket. If you decide to have the repair done as opposed to getting a new vehicle, it's best to let a professional mechanic.
Head Gasket Replacement Cost Estimates
The average cost for a Head Gasket Replacement is between $2,427 and $3,190 but can vary from car to car.