Thru Hull Scupper Plastic 1 1/2"

Function and technical context

The thru-hull is a structural hull accessory that allows water, fuel or fluids to pass through the lining of the boat in a watertight manner, and is usually used as a scupper or drain on decks, cockpits and stern lockers. This 1½" model is made of technical plastic with high resistance to marine corrosion, ideal for installations in humid environments where conventional metals can degrade due to electrolysis or prolonged exposure to salt. Its geometry – with an external diameter of 75 mm, total height of 102 mm and internal passage of 46.5 mm – guarantees an adequate drainage flow and a reliable seal against the ingress of water when correctly installed with a tightening gasket. Faulty installation or a deteriorated thru-hull can compromise the watertightness of the hull, with the consequent risk of water entry and progressive sinking, which makes it an active safety element of the boat.

When to replace this part?

The most common symptoms of a plastic thru-hull in poor condition are the appearance of humidity or dripping around the fitting in the bilge, visible deformations in the body due to exposure to mechanical loads or UV rays, and cracking of the plastic, especially in boats with several years of use. It is recommended to visually inspect all thru-hulls at each docking or seasonal maintenance, checking the tightness of the locknut and the condition of the sealing gasket. Preventively replacing any thru-hull that has microcracks or looseness prevents serious breakdowns that are difficult and expensive to remedy in navigation.

Compatibility table