Whether it’s just general wear and tear or a hidden rock just below the surface, boat fins will inevitably need to be replaced from time to time. As long as you have the right tools for the job, the replacement process is quite simple.

• You will need a thick rag, mallet, silicone gun, plastic razor, pick, general purpose adhesive remover, microfiber rag, and of course a spare fin to replace the old/broken one.
• First, remove as much glue as possible from the notch in front of the fin with your pick and plastic razor.
• Next, wrap the thick rag around the head of the mallet and proceed to tap the fin forward into the notch so you can take it out.
• To remove the fin, lift the back first. With the rear out of the fin slot, you can then lift the front of the fin up and out.
• With the entire fin removed, wipe off any glue that may have stuck to the fin on its way out, and make another pass on the exposed fin slot with your plastic razor to remove any additional excess you see.
• If there are still spots of excess glue lingering in the fin slot after your passes with the plastic razor and pick, grab your general-purpose adhesive remover and microfiber rag to handle them. Use the plastic razor as necessary to extract the loosened glue, and make sure to have a glove on the hand using the adhesive remover cloth so you don’t get it on your skin.
• With the fin slot completely clean, you can now take your new/spare fin and install it by first slotting in the front to lock it in, then sliding it down and back to line it up with the rudder.
• Once the new/spare fin is installed, secure it in place by loading up your silicone gun and gently applying a small amount into the notch in front of the fin. You do not need to apply the silicone anywhere else around the fin.
• After that, wipe off the excess silicone, let it dry, and your boat will be ready for use again.