Repairing a Leaky Windshield


Webmaster's Note: In response to a question from an owner on the SENTOA Listserv, Buddy Brown from Nordic Tugs, Inc., sent the following response on how to repair a leaking windshield on a Nordic Tug

Leaking windshields are a challenge. First determine if the leak is from the glass to the frame or the frame to the boat. Pull the trim ring and look for a rusty looking water trail. If it is the glass in its own frame
leaking, your best bet is your local glass shop...automotive. You could also check Diamond Sea-glaze's website for service info.

If the leak is from the frame to the boat: Unfortunately to do it correctly, the window needs to come out, be cleaned up, re-sealed and re-installed. Use extreme caution and patience. The frame will bend if you are aggressive.

Removal procedure: You already pulled the trim ring. Put a double-thick layer of duct tape around the outside of the window to protect the boat. As you work watch the condition of the duct tape and replace as needed. Through the years I have found the 1 to 1-1/4" Red Devil metal puttyknives work the best as they are quite flexible (you may need to sharpen them). Get a few of them as you will destroy them.

Start at a corner and drive a putty knife under the frame, stay on top of the duct tape. The flange is only an inch wide do not drive the knife under the frame too far as you can damage the powder coat. The body of the putty knife can damage the powder coat on the edges as well. It could be a bugger to start; tap the knife along cutting the seal as you go. Using a heat gun on the frame will help to soften the sealant, it will stretch and cut easier.

Did I mention be patient! Start a second knife the other direction from the corner to try to start the separation from the boat...don't try to force the window out. Drive the knives under the frame at a 45º or so angle to cut the sealant. You will have to pull the knives out and restart constantly as they are driving toward the window not damage the frames with the knives and hammer. As you drive the knives away from the corner you started you can start driving shallow wedges in behind the knives...gently, don't bend the frame. The further you go the easier it gets. That should get the window out, and likely you can see where the leak was by the condition of the seal. Now clean up the mess.

Re-installation: Apply liberal amounts of polyurethane sealant (we use Sikaflex 291; 5200 has too high of tensile) to the mating flange and re-install the window. Tighten the screws on the trim ring inside. Clean up the ooze with a plastic scraper, 3M Adhesive Remover (or equivalent) and rags. Be sure you see no voids in the final seal around the perimeter of the window.

Sit back with the beverage of choice and admire your work!

Buddy Brown
Facilities, Safety and Compliance
Nordic Tugs, Inc.

360-757-8847 x107


Copyright © 2012 SENTOA • Last Update November 30, 2017 • Questions? Contact the SENTOA Officers.