Mortimer Brewster wrote:
I had the same problem on my KZ. The window openings are oversized, the window being held in place with compression. This leaves a gap beneath the window. Over time the bouncing/vibrations of road travel take their toll, and the window shifts downward. This leads to small gaps on the top corners where water can intrude.
My solution was to shim the window up using some PVC trim that custom cut to fit. Be sure not to shim it so it's centered in the opening. This will prevent future sagging of the window. Nothing more than butyl tape is needed.
I would also inspect your other windows. If a window has sagged the butyl tape will leave a trace of it above the window. If you see this I'd go ahead and reset the window.
Thank you so much for this valuable information Mortimer! I would definitely check for any loose fit of the frame into the wall when I'll remove the window to fix the sealing and make the appropriate shimming.
I'll also check if I found some way to reinforce from the inside the very thin luan of the inside wall because when water spill around the window framing, it made a small "bubble" in the luan of about 3x3 inches and when it dried up completely the luan was cracked a little bit in the bubble and it's weird because it feels like if the wall is totally empty behind luan, like to isolation or nothing... so when I’ll remove the window I assume I'll have some kind of access to inside the wall and spray some expandable urethane behind the "bubble" to ensure if someone push on it it wont damage the wall...
For now the window is not leaking anymore because I made a quick "emergency" seal from outside the frame with RV caulk and it's 100% sealed for now. But now I need to make a more permanent fix to the seal. :-)
Thanks again for your advice!!
