411 Leaking Port Lights

Aug 10, 2014
4
Beneteau 411 St. Clair Shores, MI
I have a 1999 411 with a leaking Lewmar, old style, port light. I've replaced the rubber gasket and recaulked the seals/slits on the outside of the port light. Water still streams in around the aft closure on the window. Any ideas or should I take it all apart and start over?
 
Feb 21, 2013
4,638
Hunter 46 Point Richmond, CA
Per this Lewmar article My hatch/portlight is leaking. What should I do? | Lewmar: It is important to establish the leak path. Where the water finally appears in side the boat is not always a good indication of the leak path. The easiest way to trace a leak is to wait for a dry day perform a leak test by spraying water on the portlight with a shore water hose. Establishing the leak path may be difficult if there is a significant level of condensation on the hatch/portlight. Possible leak paths are:
  • Under the lower frame..........caused by insufficient bedding compound between the low frame and the deck, or the compound breaking down over time. It may also occur if the cut out in the deck is too big or the hatch/portlight is not mounted on a flat surface.
  • Between the lower frame and the rubber seal (gasket) .......caused by the upper frame being distorted or a loss of seal pressure. Lay a straight edge along the sides of the hatch and also diagonally across the lid to check for twist. Also check the seal for dirt or damage. Try closing the lid down on a sheet of paper. If the paper can be slid out when the hatch is closed the seal is not compressing.
  • Through the holes in the acrylic used on some products to fasten the handles, hinges or friction levers. The handles have a standard O-ring under the plastic moulding on the outside of the acrylic. This should be cleaned and lightly lubricated with silicone grease.
  • Between the acrylic and the upper frame......caused by a breakdown in the adhesion between the sealant and the upper frame or acrylic. Try gently pushing the acrylic up out of the frame and look for movement.
Do an interenet search on "fixing a leaking Lewmar, old style, port lighs" and you will find articles and threads on this subject like these: Fix for Leaking Lewmar Portlight Windows – Foghorn Lullaby AND Remedy for leaking Lewmar portholes | Sailboat Owners Forums
 
Last edited:
Aug 10, 2014
4
Beneteau 411 St. Clair Shores, MI
Per this Lewmar article My hatch/portlight is leaking. What should I do? | Lewmar: It is important to establish the leak path. Where the water finally appears in side the boat is not always a good indication of the leak path. The easiest way to trace a leak is to wait for a dry day perform a leak test by spraying water on the portlight with a shore water hose. Establishing the leak path may be difficult if there is a significant level of condensation on the hatch/portlight. Possible leak paths are:
  • Under the lower frame..........caused by insufficient bedding compound between the low frame and the deck, or the compound breaking down over time. It may also occur if the cut out in the deck is too big or the hatch/portlight is not mounted on a flat surface.
  • Between the lower frame and the rubber seal (gasket) .......caused by the upper frame being distorted or a loss of seal pressure. Lay a straight edge along the sides of the hatch and also diagonally across the lid to check for twist. Also check the seal for dirt or damage. Try closing the lid down on a sheet of paper. If the paper can be slid out when the hatch is closed the seal is not compressing.
  • Through the holes in the acrylic used on some products to fasten the handles, hinges or friction levers. The handles have a standard O-ring under the plastic moulding on the outside of the acrylic. This should be cleaned and lightly lubricated with silicone grease.
  • Between the acrylic and the upper frame......caused by a breakdown in the adhesion between the sealant and the upper frame or acrylic. Try gently pushing the acrylic up out of the frame and look for movement.
Do an interenet search on "fixing a leaking Lewmar, old style, port lighs" and you will find articles and threads on this subject like these: Fix for Leaking Lewmar Portlight Windows – Foghorn Lullaby AND Remedy for leaking Lewmar portholes | Sailboat Owners Forums
Thanks so much. This is a really good list of things to check!