What to use to seal windows

[seadaddler]

I am pretty sure my head window is leaking and now I think my windows in saloon are leaking on port side
in my 07 H-36 and so wondering what sealer to use to reseal when I attempt to take out windows and reseal.
Long time ago zI think some one said to use something with a 95 number in it but don’t remember for sure.
Seadaddler

 

[MFD]

If these have positive fastening (frames with bolts) I would go with butyl tape. It is easy to work with.
Also when it is time to do it again, easy to remove and simple cleaning/prep to replace.
Another bonus - no curing time, so you have all the time in the world to get it setup all nice. And easy to trim off any extra.

EDIT: And you can get butyl tape in white, gray, etc.

 

[BAD ORCA]

DOW 795 if youre putting acrylic lenses back in metal frames for opening hatches.

 

[Foswick]

It depends on if you need to reseal the window within the frame or the frame to the cabin. And, then it depends on what the window and frame are made of.

On my previous boat (Catalina 27), I rebedded all of the ports, as some were leaking. These were tempered glass in aluminum frames. I used Dowsil 795 to seal the glass in the frame, and I think that is a pretty common solution.

Sealing the frame into the cabin wall though ...

Initially, I used 3M 4000, as recommended by several people. A truly messy, nasty job and I never did get a good seal. All I did was take 10 years off my life from the stress. I removed all ports, cleaned them up, and rebedded with butyl tape. Once I cleaned up the old adhesive and started over, that job with butyl tape took maybe an hour or so for all 6 ports and was super simple. Didn't leak for the the next 15-ish years we owned her and never had an issue.