What is the purpose of a compression check on a reciprocating engine?

The purpose of a compression check on a reciprocating engine is to assess the health of the engine's cylinders and sealing components. This diagnostic procedure involves measuring the pressure within the cylinders during the compression stroke. By doing so, it helps to determine whether the piston rings, cylinder walls, and valve sealing areas are functioning correctly. A proper seal is essential for maintaining adequate pressure, which directly influences engine performance, efficiency, and overall reliability.

High compression readings indicate good sealing and health of the engine, while low readings may suggest issues such as worn piston rings, leaking valves, or other internal wear. This information is vital for diagnosing potential problems early on, which can prevent more extensive damage and costly repairs down the line. Monitoring cylinder pressure through compression checks is a key aspect of routine engine maintenance and is critical for ensuring that the engine operates efficiently and effectively.