Because they have to be able to seal a variety of components all at once, head gaskets are among the most overworked gaskets in an engine. They prevent the engine’s coolant, oil, and combustion compression from coming into contact with one another and the outside world. When head gaskets do blow, there are a few different ways in which they can fail in that process (this is why they are not always easy to diagnose). Check out the best products for that.
When a head gasket starts to leak, there are a few distinct ways that the problem may manifest itself. The following is a list of some of the most frequent signs of a head gasket that has blown:
Oil to exterior leak
Certainly one of the most noticeable symptoms. You will notice oil leaking in the engine bay and sometimes even on your driveway or parking lot if the head gasket fails between the engine’s internal oil system and the external world (that is, outside the engine). If the head gasket fails, the engine’s internal oil system is exposed to the outside world.
Despite the fact that this particular sort of head gasket leak is not as immediately threatening as some of the other varieties of head gasket failure, it still requires care and, in our experience, will gradually get worse over time and with increased mileage driven. The oil pressure in your engine may drop as a direct consequence of this type of leak. If you observe this, you need to pay close attention to the level of engine oil, and you shouldn’t let the level drop too low. If necessary, put more in the tank.
A leak of coolant to the outside
This is a comment that we get from our clients rather frequently. It is not as simple to identify as a leak from the oil to the outside, but it is rather common.
The fact that leaking coolant either drips to the ground or evaporates while the vehicle is in motion makes it more difficult to observe. This indicates that you have a limited ability to visually identify the source of the head gasket leak. A coolant leak can be slow, moderate, or quite aggressive depending on whether or not a head gasket fails between an engine water channel and the outside of the engine.
After some time has passed, the level of coolant in your system will begin to drop, and you will find that you need to often add more. If the coolant level in your system drops too low, there is a risk of it overheating.
Leakage of coolant into the oil
In a relatively short amount of time, engine oil and coolant will become mixed together if your head gasket fails somewhere between an oil channel and a coolant channel. This will result in contaminated oil, sometimes known as oil that has the appearance of a blended “milkshake,” rather than oil that is clean. This is the process that is taking place in your engine when a blown head gasket is said to create a white, creamy sludge of your oil. It appears that the coolant has contaminated the oil in your vehicle, and the appearance you see is a direct result of this contamination.
However, hold on there — it is also normal for it to go in the opposite direction, from oil to coolant. This is due to the fact that the pressure in the oil channel is significantly greater than the pressure in the coolant. Because of this, the coolant will become milky, and you will find an oil film inside the cooling system.
Compression to outside leak
Compression-to-outside leaks do happen in some circumstances, especially if the engine design is recognized for this type of problem, but we do not hear about this type of head gasket symptom nearly as often as we hear about other of the head gasket symptoms listed above. If your vehicle is making a loud “ticking” noise while it is idling, the problem may be a compression-to-outside leak, which indicates that some of your engine’s compression is leaking out of the engine and into the surrounding environment (when you drive regularly the tick often goes silent). When a head gasket fails in this way, the car will typically have a rough idle, jerky acceleration, and a loss of power.
Compression leak to coolant
Another symptom that has been brought to our attention, but not as frequently as some of the others that have been discussed thus far. If your head gasket fails between a cylinder and a water channel, the crack or fissure that results will allow exhaust gases to flow into the cooling system. This will result in a pressured cooling system (due to exhaust gas accumulation), which will eventually cause your vehicle to overheat. Due to the increased pressure in the cooling system, it is possible for the hoses’ fittings to be blown off, which would result in a significant issue almost immediately.
To what extent? This, unfortunately, can lead to the radiator, hoses, and other components of the cooling system being destroyed. This particular form of leak also causes a significant decrease in the volume of coolant, which in turn leads to rapid overheating.
This particular form of compression leak makes it possible for coolant to spill into the cylinder itself, where it is then consumed by combustion as steam. This results in the telltale sign of a blown head gasket, which is “white smoke” flowing out of the exhaust pipe, as well as a scent that is unmistakably sweet both within the cockpit (occasionally) and outside the car (all the time). Another disadvantage is that as this coolant is consumed by the cylinders, it must pass through your exhaust and emissions systems, which increases the risk of damage to both of those systems.
A loss of compression between the cylinders
It is possible for the compression in your engine to leak from one cylinder to another if the head gasket that separates the cylinder walls fails. Compression can also be lost in your vehicle if the head gasket has blown out, which is another possibility. Misfires, jerky idle and acceleration, and a loss of power are the typical symptoms of the type of head gasket leak described here (most noticeable during acceleration).
Compression leak into oil channels
Compression will leak into the oil system if the head gasket that is located between the cylinder and an oil channel fails to seal properly. This results in your oil system becoming pressured, which is not a desirable state to be in at all. Something that we have witnessed a large number of times, hot compression gasses will destroy the lubrication of key bearings, such as the main bearing that is found on the crankshaft.
This symptom also causes the piston to draw oil into the cylinder, where it will be burned off as part of the regular combustion process. This is because the piston is drawing oil into the cylinder. As you probably have guessed, this will eventually lead to a decline in oil levels, and it will also mean that you see the dreaded “blue smoke” from the exhaust, which is of course caused by your engine burning oil.