Sounds like an old ski and the tubes have deteriorated. Should not hamper steering but will let water in. Basically you have to replace the tubes, They used polyurethane for a few skis, either because nylon was unavailable or for some other reason and it does not seem to like either the heat or the water.
I have a way to replace them without opening up the ski. Not sure were you are but if in Western Australia I can help.