Conducting a Cylinder Compression Test. Before conducting a compression test, disable the ignition and the fuel injection system if the engine is so equipped. Prop the throttle plate into a wide open position to allow an unrestricted amount of air to enter the cylinders during the test. Remove all of the engine's spark plugs.
Connect a remote starter button to the starter system. There are may types of compression gauges available. The screw in type tends to be the most accurate and easiest to use. Carefully install the gauge into the spark hole of the first cylinder.
Connect a battery charger to the car to allow the engine to crank at consistent and normal speeds needed for accurate test result. Depress the remote starter button and observe the gauge's reading after the first engine revolution. Allow the engine to turn through four revolutions and observe the reading after the fourth. he pressure from The reading should increase with each revolution. Readings observed should be recorded. Before removing the gauge from the cylinder, you can release the pressure from it using the valve on the gauge.
After testing all the cylinders. If one or more cylinders is much lower than the other, continue nder with testing those cylinder with the test. Squirt a small amount of oilring sealing into weak cylinder. Reinstall the compression gauge into that cylinder and conduct the test. If the reading increases with the presence of oil in the cylinder, the most likely cause of the original low readings was poor piston sealing. Using oil during a compression test is normally referred to as a wet test.
After testing all the cylinders. If one or more cylinders is much lower than the other, continue nder with testing those cylinder with the test. Squirt a small amount of oilring sealing into weak cylinder. Reinstall the compression gauge into that cylinder and conduct the test. If the reading increases with the presence of oil in the cylinder, the most likely cause of the original low readings was poor piston sealing. Using oil during a compression test is normally referred to as a wet test.
