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Feature effectively look below the surface or find damage hidden inside a casting. In this case, pressure testing will help you see what’s going wrong inside the engine.
Cracking is an indication that an area is experiencing more stress than it can handle.
Vacuum Testing: This is the same basic idea as pressure testing, except in reverse. Instead of using air pressure to test the cooling jackets for leaks, vacuum is used on a head or block after the water outlets have been plugged. If the casting holds vacuum, there are no leaks. But if it doesn’t, you’ve found a leaker. Unfortunately, this technique does not use water or dye to pinpoint the leak, so you still have to use one of the other techniques to find the leak. It’s mostly a quick check for verifying the integrity of a casting. Ultrasonic Testing: More commonly used in industrial and aviation applications, ultrasonics can also be used to find internal flaws in castings and other parts. The technology uses sound waves to find cracks. A
transponder generates an acoustic signal (up to 25 MHz) that passes into and through the part. Cracks or flaws will reflect some of the sound waves back to the detector, which allows the information to be displayed on the tester.
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The best applications for ultrasonic testing include heavy castings, large shafts and expensive parts that may be used for racing or extremeduty service. Ultrasonics can also be used to check the integrity of welds and
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