I have a 1987 300 Weekender. It...

[TitanTn]

I have a 1987 300 Weekender. It has the famous side windows from the 80s that have leak problems. After spending some time inspecting the windows to see how they work - I've come to the conclusion that they're just simply a bad design. As water runs down the plexiglass it runs into the track that the plexiglass rides in. There's just not a way for that water to exit. When the track fills, it overflows into the next inside track, and when that fills it overflows into the cabin. Anyone have some suggestions for this? I'm thinking about drilling some drain holes at the bottom of the outside track, but not sure if I should be doing anything that extreme before trying something else. Any ideas?

[Wyoming_White_C]

I have an '86 Sundancer 270 with a leaky window and I am preparing to remove it and rebed it with 3M 4000 UV. I came across the "gutters" in this link and I think that I will order them as well. The idea is to deflect the runoff so it does not flow over the window assembly. I can't see how they could hurt anything other than costing you $50.
http://rvgutters.com/ezemarinegutters.aspx

[TitanTn]

Looks like a nice product. I've pulled my windows and re-bedded also. That's not where mine is leaking. It's the tracks that the "windows" sit in and slide. There's no way for the water to escape. There are some slotted drains with little covers over them, but the rubber track doesn't have any egress points for the water. I recently cut the rubber track near these slotted drain points and it seems to be doing much better. I still need to find something to fit between the outer, sliding window and the stationary, inner window. I assume there's something that is supposed to be there to fill that gap, but there isn't on mine.

[Wyoming_White_C]

I plan on checking that too, once I get the window out. Makes sense that there needs to be drainage once the water runs down the window into the track. There are several articles online by a guy named David Pascoe talking about windows such as these. His big issue is that if there is any flexing around the window frame due to walking on the deck, etc., it will break the seal. There is even a picture of a Sundancer 270 in one of his articles as an example of a bad design. I found it interesting when taking out the screws that eight of them are bolts with nuts on the inside, while the rest are just screws and come right out. This may be something that was done by a previous owner. Getting at the nuts on the inside necessitates removing some trim, the bamboo curtain and peeling back the carpeting an inch or so. I think that I can grip them with some small pointed vice grips while I unscrew from the outside. I think that I will install the gutters as well, just as a precautionary measure.

[Wyoming_White_C]

Pulled the window out this morning and Pascoe was spot on. The seal along the back two thirds of the top was completely compromised to the point where dirt had blown in through the crack. I scraped all the caulk off the fiberglass and then cleaned it with 409 and then acetone. Brought the window assembly home to work on it on the bench. There are three drains along the bottom of the track, covered with plastic covers. I have attached a pic of one with the plastic cover removed. Took the window out into the back yard and cleaned the tracks out really well with a hose and water flowed freely out of the drains, so I feel good about that. Perhaps yours were clogged up with dirt or even salt. Mine had gaps in the rubber track behind the drains to allow water out. As you said, maybe that was your problem.

[Wyoming_White_C]

Also, I meant to say that I might try to find a sign that says "No Step" like you see on airplane wings and put it on the deck right above the window. Other than looking completely dorky, it might do some good.

[TitanTn]

Sounds like you're well on your way to fixing yours. I think my issue is that rubber track. It may not be the right one or something because there's no slot where those drains are. I'm also missing the flocking between the sliding window and the stationary window on the starboard side. I'll have to figure out what to do about that.