What typically causes an engine to lock?

An engine locking occurs when the internal components seize up, preventing the engine from turning over. One of the primary causes of this issue is low oil. Engine oil lubricates the moving parts, reducing friction and preventing wear. When oil levels are insufficient, it can lead to increased friction between components, causing them to heat up significantly. This excessive heat can cause the engine parts to expand, ultimately leading to a complete seizure where the engine can no longer rotate.

While overheating can sometimes overlap with low oil issues, it is the lack of adequate lubrication that directly leads to the mechanical failure associated with an engine lock. Other factors, like fuel contamination, can affect engine performance but do not directly cause the engine to seize. Similarly, high speed alone is not a cause; it can exacerbate existing problems, especially if oil levels are low. Understanding the critical role of oil in engine operation emphasizes the importance of regular maintenance and checks for oil levels to prevent locking.