Blue Sea Cable Clam
Watertight Pass-Through for Cables

Marine Cable clams allow fish finder cables to pass through the hull of your kayak while maintaining watertight integrity. These are perfect for rigging sit on top fishing kayaks with fish finders. They are essential items if your objective is to penetrate the wall of the kayak.

Not only do the clams keep water out of the internal section of your kayak, but it clamps your cable firmly so it can't slide back and forth. Proper installation is an important step in kayak rigging to ensure water-tightness.

The Blue Sea Clam is easy to install and can be attached from start to finish in about  20 minutes. Less than that if you have done it before.

I have three sizes of clams. Each size clam has a maximum diameter cable it is recommended for. Be sure to read the installation instructions below before making a choice on the cable clam size.

Blue Sea Cable Clam Parts List

  • Top White Plastic Compression Ring
  • Black Rubber Seal (Looks like a Hockey Puck)
  • Plastic Deck Ring with Rubber Gasket
  • Stainless Steel Screws

Installation Instructions (Also on Package)

Mounting a fish finder on most sit on top fishing kayaks will require you to drill a hole through the top of your kayak for the cables to pass through.  The mounting location for most fish finders will be in the front equipment rib near the forward hatch. Your hole can be drilled at many location near the mounting spot for your fish finder.

Important Pre-installation Information:

  1. Marine clams attach in two parts: the base plate that screws onto the kayak hull then the compression cap that bolt into the base plate.
  2. The hole where the clam will be installed needs to be large enough to accommodate  the largest portion of the cable that must pass through, not just the wire diameter. This most likely means the plug that connects the cable to the back of the fish finder.
  3. The location of the clam must be on a flat, smooth portion of the kayak wall in a space large enough to accommodate the entire diameter of the clam.
  4. Clams come in different sizes. Choose the size designed to hold the cable diameter of both fish finder cables as well as being large enough for the base to cover the drilled hole while still leaving room for the stainless steel screws to attach to the hull.

Detailed Installation Instructions:

  • Locate the spot where you want to mount the cable clam.
  • Drill the proper sized hole in the kayak where you want the wires to pass through the hull.
  • Place the wires though the hole leaving enough to easily attach to the fish finder. 
  • Place the rubber gasket and base plate over the hole (topside) and attach with stainless steel screws provided in kit.
  • Take the rubber seal (looks like a hockey puck) and drill a hole in the center of the seal slightly smaller than the diameter of your cables.
  • Take a razor blade and slice through the seal from an outside edge to the inside of the drilled hole. The cables will slide though the slit to the center hole.
  • Push or pull the seal to the exact place where you want it to go.
  • Slide the compression cap over the cables and seal and attach the cap to the base plate with the bolts provided.
  • Compression cap compresses seal making the junction water resistant.
  • Don't forget to purchase our Kayak Battery Power kit to power your fish finder.
  • You're done with the Installation.

PDF Cable Clam Dimensioned Drawings

Small Clam Size 1001
Medium Clam Size 1002
Large Clam Size 1003


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