Pontoon Boat - Filling Basics

[atvaholic]

Hi, I have a water skeeter pontoon boat, im not sure the model but I have had it for about 4 years. I seem to have a problem filling the bladders substantially. The problem is, the "valve" system seems to stay open when I remove the pump and I seem to lose significant amount of air before I can close it.

I'm sure im doing something wrong...is there a trick to keeping this full? My float tube automatically closes as soon as I remove the pump fitting...any ideas?
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