The head gasket is a piece of reinforced metal that sits between the engine head and engine block. Its seal maintains pressure within the engine necessary for it to function.
Modern gaskets are designed to handle minor imperfections, but they can still break down. Previously, head gaskets needed sealants or adhesives to install, but not anymore. So instead, they now have built-in technology to seal themselves with a dry installation.
The holes in a head gasket are for different things: large holes for cylinders, medium holes for bolts, and small holes for coolant.
The most common sign of a head gasket needing repair is if coolant or oil leaks around your engine head. This is a standard indicator that the head gasket is no longer sealed to the engine.
If you notice your oil is becoming milky or more tan, this can be a sign of a blown head gasket. This is what happens when coolant from the engine contaminates the oil.
If there’s bubbling inside the radiator or the coolant reservoir, that means the system has gotten some air in it. Often, this occurs because of a leaking or blown gasket.
Blowing a gasket can cause overheating in the engine. It can also damage many different engine parts. If you notice overheating, immediately turn off your engine until you can determine the source of the overheating. However, never remove the radiator cap and check the coolant during this process. You will get burning hot coolant sprayed on you and need to go to the emergency room.
If coolant makes its way into the engine, you may see white smoke or water vapor come out from your exhaust pipe. One way that coolant can make it into the engine is through a bad head gasket.
There are only a few options for a head gasket repair, and none of them feel great. If you opt to repair it yourself, you’ll need to have experience rebuilding engines, as this is considered an expert-level job. Therefore, you should only attempt it with proper tools and lots of experience.
You can also opt to pay for a whole new engine. But this will often cost much more than a repair.
If you opt to pay for a repair, the technicians will have to perform tests to confirm the head gasket is blown. Then, they will need to remove half of the engine to access the head gasket. Once open, additional problems may be spotted, taking more time, labor, and, therefore, money.
Depending on the damage, you may need a head gasket repair or replacement. The head gasket repair cost will depend on many factors, but you can expect a range of $1,000-$3,000 for a proper head gasket repair.
At-home tests for a potentially blown gasket you can use are:
Once the car is sitting idle, open the hood and remove the radiator cap before starting it up. If there’s bubbling, that’s a sign of a significant leak.
A coolant pressure tester kit can check the pressure of the vehicle’s cooling system. If it’s low pressure, the leak may be caused by a blown head gasket.
These head gasket leak tester kits, also known as compression leak testers, can tell if there’s a head gasket leak.
Over time, the head gasket deals with constant changes in temperature, head movement, and intense pressures. As a result, the gasket will naturally fail after it loses integrity and breaks down as it gets older.
Without a flat surface, the gasket can leak. Warping can happen with aluminum parts that wear more quickly than steel. Heat can damage the engine block or the cylinder head, causing it to crack or warp.
If somebody has installed the head gasket improperly or has reinstalled it improperly, it may get a weakness or vulnerability that can cause it to fail eventually.