How to Seal Around Boat Port Lights

How to Seal Around Boat Port Lights
The port lights on your boat allow daylight to shine in and brighten interior cabins. They are important because daylight lets you save your precious battery power for nighttime. Even after the sun goes down, your port lights let you keep an eye on what is going on outside when you're in the cabin. As important as they are, leaks in port lights are very damaging. The water enters a cabin that usually has little airflow, so mold develops quickly, and there is less drainage in a cabin than there is on the deck. If you catch leaks early, you can often fix them just by resealing the port.


Difficulty: Moderately Challenging

Things You’ll Need:
  • Gasket Marine sealant Kerosene Dowel stick Drill Aluminum rivets Fine sandpaper Tape
  • Gasket
  • Marine sealant
  • Kerosene
  • Dowel stick
  • Drill
  • Aluminum rivets
  • Fine sandpaper
  • Tape
Step 1
Buy the appropriate sized gasket for your brand of port light. Check the boat owners manual if you are not sure what type of port light it is. Buy marine-quality sealant for the finishing seal. The type of sealant you choose depends on the surface material of the boat (metal, wood or fiberglass) and the material of the port light rim (plastic or metal). However, never purchase any sealant for your boat that is not marine grade. Ordinary sealants may not hold up to the weather or even the expansion that occurs because of the pounding motion of a boat.
Step 2
Remove the port light by taking out the screws on the inside. Run a knife under the existing seal on the outside. Clean the entire unit. Soak any surfaces with old sealant that won't come off with kerosene. Rinse completely.
Step 3
Push the gasket seal into the channel around the glass with a wood dowel stick. Heat up stubborn gaskets with a hairdryer just enough to make it a little more elastic. Reassemble the rim around the glass. The alignment may change and require re-drilling of the rivet holes. Use aluminum rivets to attach the pieces and marine sealant to make them waterproof.
Step 4
Run a bead of sealant around the rim of the port light under the lip. Place the port light back into its opening. Some sanding may be required to widen the opening by a small amount. Use fine-grade sandpaper. Tape in place. Screw in the port light from the inside of the cabin. Remove tape outside.

Article Written By Tami Parrington

Tami Parrington is the author of five novels along with being a successful SEO and content writer for the past three years. Parrington's journalism experience includes writing for eHow on medical, health and home-related topics as well as writing articles about the types of animals she has raised for years.

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