Funny how sometimes a window won't leak running a hose on it but it will when it rains. I doubt the window will fall
out by removing the clamp ring. Our Uhaul
window had some sealant that was so hard I didn't know if I could get it out. It's very hard to track the water back to the source because of the way it will travel. I finally used Proflex RV sealant that comes in a caulk tube to stop my leak. Used it on the shell seam, the rubber weatherstrip that holds the window in, and inside behind the clamp ring where there was a gap in the original caulk. I just didn't want to pull that window out, even though that may have been the best fix. Sometimes I like to go for the simple fix and "let sleeping dogs lay"