Genuine BMW 11121729907 Cylinder Head Gasket – BMW | 11121720077 11121729897

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The head gaskets in your BMW are the seal between an internal combustion engine’s engine block and cylinder head. They are made of compressible metal, organic fiber, or a combination of both. They can seal high engine combustion pressures and prevent engine oil and coolant from seeping into the engine cylinders. Some head gaskets are large flat gaskets with holes for the cylinders in the block to mate with the combustion chambers of the cylinder head. Other head gaskets are rings that seal each individual cylinder to the cylinder head combustion chambers.

Head gaskets are single-use gaskets and require a precise amount of force between the cylinder head and engine block to seal properly. Once the cylinder head is securely bolted in place on the engine block, the head gasket compresses to fill in even the tiniest gap to seal the combustion chambers. However, if the cylinder head is loosened or the head is removed, the head gasket will not seal again and must be replaced.

Head gaskets fail when they lose their ability to seal in combustion pressure and prevent oil and coolant from leaking into the engine cylinders or the engine’s exterior. Head gaskets failing can be caused by an overheated engine, excessive combustion pressure from engine RPMs being consistently high, or even the age of the gaskets.

Severe head gasket leaks will cause your engine not to start or run rough from improper cylinder compression. Smaller head gasket leaks may be less noticeable but can be just as bad for your engine. Oil leaking into the cylinders will create black smoke, and coolant in the cylinders will create white smoke; both can contaminate your vehicle’s catalytic converter and engine sensors and lead to critical engine failure.

Replacing Your BMW Head Gasket

When replacing the head gaskets in your BMW, the mating surfaces of the cylinder head, engine block, and cylinders must be free of oil and debris, and the cylinder head must be secure to the proper torque specification. Oil, debris, or a cylinder head not fully secure will prevent the gasket from sealing to the engine surfaces, while an over-tightened cylinder can split the gasket creating oil, coolant, and compression leaks.

BMW Head Gaskets.