Greetings from Minnesota!
I have a 1992 Gulfstream Conquest. The lower "channel" on the inside of my non-opening rear window fills with water when it rains and overflows onto the bedding, pillows, and gets behind the wallpaper at the head of the bed and forms mildew/mold.
Attached is a 7 second video of the inside of my window showing water in the inside bottom window channel. There's also a photo of the channel with water in it. Note that this is on the inside of the motorhome.
I have not yet located the source of the leak. I've had a new rubber coating applied to my roof and the integrity of that is not being questioned as it it new and seems fine. I'm convinced that the leak originates with the window itself....but... the seal between the fiberglass and the window seems fine.
After seeing a You Tube video (below) on removing the window and applying new butyl tape, I was going to follow the instructions in this you tube video.
However...I decided to do a "test" first and so I applied some vinyl tape at the top of my window (before it rained) to see if re-sealing the window with new butyl tape, as explained in the you tube video would solve my problem.
Below is a photo of my window with the vinyl "test" tape...which didn't keep the water out.
After applying the tape to the window before it rained, after it rained, there was fresh water in the lower portion of the window channel...so the tape didn't cover the problem area. I now doubt that removing the window and applying new butyl tape will solve the problem because the vinyl tape didn't.
Does anyone have any suggestions as to how to locate the problem and solve it? Any advice would be much appreciated.