This document provides step-by-step instructions for conducting an engine compression test. It covers the necessary preparation steps, such as warming up the engine, disconnecting spark plug wires, and disabling the ignition system to prevent the engine from starting during testing.
The guide details how to install the compression gauge adapter into a spark plug well and crank the engine to obtain pressure readings. It also explains how to interpret the results to diagnose issues like sticking valves, carbon buildup, head gasket failures, or worn piston rings.
Run the engine for about ten minutes or until it reaches normal operating temperature.
Crank the engine for at least four compression strokes or until the pressure reading stops rising.
The reading should not vary more than 10% from cylinder to cylinder.