Kompressionarpróf

Kompressionarpróf is an Icelandic term that translates to "compression test" in English. It refers to a diagnostic procedure performed on internal combustion engines to assess the mechanical condition of the cylinders. The test measures the ability of each cylinder to hold compressed air during the compression stroke of the engine cycle.

To perform a kompressionarpróf, the spark plugs are removed from the engine. A special pressure gauge, designed to screw into the spark plug hole, is then inserted into one cylinder at a time. The engine is then cranked over with the starter motor. During cranking, the piston moves up, compressing the air within the cylinder. The gauge registers the maximum pressure achieved. This process is repeated for each cylinder.

The results of a kompressionarpróf are compared to the manufacturer's specifications and to each other. Significant variations in pressure between cylinders can indicate problems such as worn piston rings, leaking valves, or a damaged cylinder head gasket. Low readings in a specific cylinder can suggest internal engine wear or damage, while consistently low readings across all cylinders might point to a more general issue like worn valve guides or incorrect valve timing. This test is a fundamental step in diagnosing engine performance issues and is often used before more invasive repairs.