If you have not had it serviced or you do not know the service history best to go ahead and service it. There is a rubber gasket between the lens and camera that needs a very small amount of lubricant periodically depending on how it is stored or used. (I, personally, do not use mine much and lubricate it once per year.) It is recommended that it be replaced yearly...that is the recommendation that was given to me. As far as water in the advance lever...There is a black piece of rubber material that covers the top of the lever. Water becomes trapped under that and can seep into the mechanism, which happened to me. A 'wire' needed replacement and the black cap removed. I am not a camera repair person. I had my camera sent out. I had purchased it used. I used it for a period of time and then sent it for maintenance. I have discovered that any piece of equipment used for diving needs to be serviced periodically and maintained with more discipline. For instance, using a Nikonos camera whether in the ocean, lake or pool needs to be rinsed or and dried after each use to remove chlorine or salt. Another piece of advice use 36 shot rolls as you can not remove film under water or for that matter change lenses, which is why I never purchased a second lens. But, the good thing is that in warmer climates where there is a lot of sunlight ISO 100 will work 60 feet under water in daylight. I hope that this is helpful.
