Cylinder Head Gasket
If there's one gasket that's exposed to the most severe conditions, it would have to be the mechanical seal between the engine block and cylinder head. Filling in the gap and allowing surfaces to mate has never been this excruciating. The cylinder head gasket has to lock in compression between cylinders to keep the forces of combustion within. The gasket also seals passages to keep engine oil or coolant from leaking into the cylinders, making sure that there won't be any anomaly in the transfer of heat and gases. This seal has to endure the engine's extreme heat-cool cycles to do this job.
Exposed to extreme heat, temperature swings, and pressure, the gasket may blow out. A blown gasket may cause minor vehicle problems or even serious troubles like engine failure if left unchecked. Early on, you should be able to spot troubles with this mechanical seal so that you can fix it right away.
Tell-tale signs of a bad head gasket
Coolant is leaking. The engine may overheat frequently when there's coolant leak. You may also spot coolant drips on the ground. Trace the leak through the outside of the engine. Use a test kit to find the real source.
Compression is lost. A broken gasket can lead to compression loss. You may then hear some hissing or tapping. Lost compression may cause engine power deficiencies. There may also be air leaks. A compression gauge can be used in this case.
Coolant has leaked into the cylinders. When the gasket breaks, coolant may find its way into the cylinders as the fluid heats up while the pressure also rises during the intake stroke. You know that there's coolant in the cylinders when there's a white cloud exiting the tailpipe.
The coolant system has air. When there's air in the coolant system, you'll notice frequent overheating and depleting coolant even without apparent leaks. This may come about at the same time the coolant has leaked into the cylinders. However, beware that air in the coolant system may also be caused by other problems. Tests may be done to confirm if this is indeed caused by a blown head gasket.
There's coolant in the oil. When coolant infiltrates the oil system, this can result in engine damage. At first, you may not notice any obvious irregularity in the operation of the engine. You won't be able to detect this symptom of a bad head gasket until you change oil. Oil may thicken and form clumps. The color may also be changed to light tan. To catch this sooner, you may have to inspect the oil cap's bottom all the way to the filler neck to search for a thick oil mixture that might already be colored tan. Also check the rocker arms.
Oil has mixed with the coolant. A fractured gasket may let oil escape into the cooling system. The oil-coolant mixture may have light tan color. This is hard to detect early on. This may go on for some time until engine problems come to light. By checking the coolant regularly, this symptom can be detected.
What may cause head gasket blowout:
- Compression stress
- Incorrect installation