Dauntless
Contributor
Go to your local dive shop and see if they have a pressure tester, if not call around as many do. Put a fishing sinker or heavy weight in the empty case, seal case, add enough water to cover, and seal the chamber, pump it up to 150 ft or so and look at it to see if you can find the leak. The chamber probably has a plexiglass top so shine a light down to watch.