4) What is the mean behind of wet compression test?

Question

Accepted Answer

Wet compression test measures the compression pressure of an engine cylinder with the addition of a small amount of oil.

Wet compression test is performed to determine if low compression in a cylinder is due to worn piston rings or cylinder walls.
In this test, a small amount of oil is added to the cylinder through the spark plug hole before performing the compression test.
If the compression pressure increases significantly after adding oil, it indicates that the low compression is due to worn piston rings.
If the compression pressure remains low even after adding oil, it suggests that the issue lies with the cylinder walls or valves.
Wet compression test helps diagnose engine problems and determine the need for repairs or replacements.

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