Thru Hull Scupper AISI 316 Stainless Steel 3/4" (Variant)

Function and technical context

The thru-hull - also called thru hull or hull pin - is the sealing element that passes through the body of the boat to allow the passage of fluids between the inside and outside of the hull: bilge evacuation, deck drainage, seawater intake or bilge discharge. Made of AISI 316 stainless steel, it offers resistance to marine corrosion much higher than standard steel, being the reference alloy for installations permanently in contact with salt water. The 3/4" measurement corresponds to the nominal diameter of the thread, determining compatibility with the hose and bottom valve installed on the same line. A defective, poorly installed or deteriorated thru-hull represents a direct risk of water entering the hull, with consequences that can lead to the sinking of the boat if it is not detected in time.

When to replace this part?

The most common symptoms that indicate the need to replace a thru-hull include: persistent moisture around the fitting in the bilge, inability to properly tighten or seal the thread due to thread wear, visible pitting in the stainless steel body (especially in waters with high concentrations of chlorides or galvanic currents) or micro-cracks detected during beaching. It is recommended to visually inspect all thru-hulls at each annual beaching and replace any unit that shows signs of active corrosion, deformation or loss of sealing. Acting preventively during grounding avoids emergency interventions in navigation, where repairing a leak is infinitely more expensive and dangerous than a scheduled dry replacement.

Compatibility table