Flooded battery compartments are often due to a battery cap that was not tightened sufficiently.
When a dive computer comes in for repair from a reported flood or moisture problem, it is always tested with the original parts in a pressure pot at a depth of 270ft, or 82.296m. This is done for several hours to find the location of the suspected water leak.
When tightening the battery cap, it is best to use a large coin like a US quarter. Smaller coins, like nickels or dimes are not recommended. The preferred method is to tighten the battery cap down all the way once, wait a few seconds, and then tighten it again. This is called the “Double Tight” check.
It is also a good idea to check the o-ring for dirt and debris (anything that will cause a sealing problem) when you remove the cap for a battery change. Be sure to keep the O-ring lubricated, but not overly, as it can make it difficult to see if there is anything that could prevent a proper seal. Another good practice is to check the battery cap from time to time for tightness between changes.
I hope this information will help you from having any problems. Please feel free to pass this along to others who own a Shearwater Petrel.
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