I never have witnessed bubbles exiting a leaking housing either. In all the cases, I've just found water inside the device (housing, strobe, light) later. I've never actually witnessed the water leaking in.seewhy said:BTW I did not notice any bubbles coming out of the housing when water enters. 2 points to note, 1) housing can still flood without the 'telltale' sign of bubbles, 2) the air inside the housing can be compressed to higher pressure and may be pop the C-clip :dunno: . But as mentioned if flooding in kept less than 10%, pressure should be minimal build up thus C-clip should be ok.
It would make sense though, that no bubbles exit (up to a point), because outside the housing, the pressure is high. Inside the housing, the pressure is low (atmospheric pressure). The housing is under stress to hold this pressure off. If a small gap appears, water is going to be forcing its way in, not air forcing its way out. Therefore it seems logical that no bubbles will be observed. When pressure inside and outside is similar, then water going in will force some air out and bubbles will be observed. The only way air-pressure inside can increase (without leaking) is, as lovells mentioned, if gas is being produced by the batteries. But don't think can become as much as the surrounding water pressure.