A leak down test is a sort of compression test which lets for measuring the ability of the cylinder to hold compression. It is usually carried out in combination with a compression measurement and together they offer very important information about the car engine and help diagnose problems in that vehicle area.
The test which lets car owners to learn about the ability of the cylinder to retain compression is what is known as the leak down test and functions by measuring the pressure in a hot engine. This test is carried out by supplying air and checking the compression through the pressure measure.
There are specific tools used so as to apply leak down tests which differ to the tools used for basic compression tests refered to as compression testers. These basic compression testers are pressure gauges that must be used while the engine is warm in order to accurately measure the maximum compression pressure. Once you learn this value you can compare it with the ideal one shown in the car owner’s manual.
If the compression pressure comes too high, this probably shows that there is an issue in the combustion chamber. On the other hand, if the compression pressure is too low, this surely is an indication there is a problem and you should look where its root is since there can be many different failures making it happen.
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The leak down testing tool inspects if the cylinder can hold any specific amount of compression without issues. Besides this, it lets you to find out where the compression leak is allowing you therefore to look for a way to fix it. Besides this, you can find if the cylinder has any issues as well as you can also learn where is the exact point in which pressurized air leaves by listening while applying the test.
Through the use of the leak down test and depending on where you hear the air escaping from you will be able to know what exactly is going on and fix it accordingly. This way, a leak down tester usually offers much more useful and complete information than the one which a compression gauge would.