How do I fix or re-seal a foam kayak bulkhead?

How do I fix or re-seal a foam kayak bulkhead?

Due to the flexing of the kayak both in transport and on the water, over time the foam wall separating the cockpit from the dry compartments (better known as a bulkhead) may come loose.

The following video will show you how to inspect, prepare, fix and re-seal your kayaks foam bulkhead to provide both strength and waterproofness.  
  1. Inspect bulkhead and identify areas that need to be sealed
  2. Tools and materials needed:
    1. Putty knife 
    2. Sharp utility knife
    3. Latex gloves
    4. Flashlight or headlamp
    5. Waterproof sealant like Sikaflex caulking (plus caulking gun) 
    6. Acetone
    7. Cloths or paper towel for clean up
    8. Vacuum
  3. Using sharp knife cut away old sealant/caulking to make room for new application
  4. Vacuum up loose bits of old sealant/caulking, then wipe clean with a bit of acetone on a cloth or paper towel
  5. Carefully apply caulking or sealant
  6. With glove on, smooth sealant with a finger tip,  Then using a a cloth, clean up any excess material
  7. Let dry for a full day or more depending on temperature and humidity (and following the application directions on sealant or caulking tube) 

If you need to replace the bulkhead completely follow these steps
1. Remove the bulkhead completely without ripping it
2. Peel any sealant residue from both the bulkhead and the inside of the kayak
3. Using coarse sandpaper, make the bonding surface rough both around the bulkhead and on the inside of the kayak
4. With the sandpaper create a chamfer (a beveled edge) around both sides of the bulkhead where contact is made with the kayak; the chamfer helps to create a strong sealant bead that will both hold and seal the bulkhead better
5. Wash the inside of the kayak and the edge of the bulkhead with acetone or lacquer thinner to make then extremely dry and clean
6. Apply a very thin layer of Sikaflex 291 (or equivalent marine sealant/adhesive) inside the kayak where the bulkhead will touch the hull and deck
7. Slide the bulkhead in place and seal it on both sides (inside the compartment and inside the cockpit) with a continuous bead of sealant, then smooth it out with a wet finger so that there are no holes or bumps left
8. Let the sealant dry for at least 24 hours before allowing it to come into contact with water, though a few days of curing time is preferable

    • Related Articles

    • How to fix bulkheads on thermoformed ABS kayaks

      If you are experiencing the issue of the bulkhead becoming separated or unglued on your Thermoformed ABS kayak, there is a relatively easy fix following these steps and with white Sikaflex marine caulking. The following article explains the steps, ...
    • How to repair or fix a cracked kayak

      There is no reason why you cannot fix a plastic ABS Thermoformed or Composite boat on your own. Using these resources and the right tools it can be done. If it seems too difficult, then many kayak dealers and also marinas offer this service. Ask ...
    • How do I fix a leaking hatch (and replace the rim with a new seal)?

      1. If the leak in your rim is small then try the following first with some silicon: Tear off the removable glue/silicon of the hatch rim where it is leaking as best you can by hand. Apply one full circle of glue to the hatch rim and screw parts, and ...
    • I own a Riot whitewater kayak. Is there an owners manual for my kayak?

      See link at bottom to view and download the Riot Whitewater Owner's Manual from 2008. Works fairly well for info on current (since we have not changed them much) and older model (discontinued) kayaks.
    • I have a small cut in the hull of my kayak. Is it possible to repair this damage?

      Yes, even though it is very hard to cut or damage our kayaks, if it does happen, then please order your repair material from one of our dealers where you bought your kayak. Please note that not all colors maybe available. You will then need a ...