However, a severely blown head gasket might lead to indirect problems that *could* prevent cranking:
* Low Compression: A major head gasket failure can cause significant loss of compression. While the engine might still crank, it might crank very slowly or weakly due to the lack of compression resisting the rotation of the crankshaft.
* Hydrolock: If coolant leaks into a cylinder due to the blown head gasket, the cylinder could become filled with liquid. This hydrolock will prevent the engine from turning over, effectively preventing cranking. This is a serious condition that can cause engine damage.
* Oil Leaks: A blown head gasket can lead to significant oil leaks, potentially reducing oil pressure to critical levels. Low oil pressure could damage the engine and, indirectly, make cranking difficult or impossible (though it's more likely to cause the engine to seize while running).
In short, while a blown head gasket itself doesn't directly prevent cranking, the consequences of a blown head gasket can create situations where the car won't crank. It's important to distinguish between the initial crank attempt and the engine's ability to run afterward (or at all).
