Just curious about something that I never really thought about before. I have read several places never to put more that 3 psi inside a pontoon when pressure testing it. I know the reasoning behind it but If the pontoons are leak free and the plugs are in the threaded bungs at the top of each chamber, is possible for the pressure to build up in the pontoon on a sunny day enough to cause a leak in the pontoon, and also a possibility to collapse the pontoons when the temperatures drop to -40 degrees in the winter time. Is this a possibility or are the pressures and vacumm that might happen not enough to cause any damage.