Attwood Marine 90° P-Trap Fuel Tank Vent, Flush Mount, 5/8 in I.D. Hose, 1-3/8 in Install Hole, ABYC Standard

Overview

The Attwood Marine 90° P-Trap Fuel Tank Vent is a flush mount fuel tank vent for permanently installed marine fuel systems using 5/8" I.D. vent hose. Its 90° P-trap layout helps keep splash water from reaching the vent line while still letting air move freely during fueling, normal running, and washdowns.

This style is a practical fit where a low profile exterior vent is needed on the hull side and where a straight hose run back to the tank is easier than forming a separate anti-siphon loop. It uses a 1-3/8" installation hole and is intended for hull thickness up to 1", making the fit points easy to check before replacing an old vent or cutting a new opening.

The internal baffle and trap arrangement is made for fuel venting duty, including ABYC H-24 ventilation requirements and ISO 10088 minimum venting area requirements. The removable cover helps with inspection, debris removal, and fuel system pressure testing without replacing the whole vent assembly.

Key features

• Flush mount 90° P-trap fuel vent for a clean hull-side installation that is less likely to snag lines, fender whips, or covers.
• Fits 5/8" I.D. fuel vent hose, a common hose size for marine tank vent plumbing.
• Requires a 1-3/8" installation hole and supports hull thickness up to 1" for straightforward fit checks during replacement or retrofit work.
• P-trap design helps reduce water entry during normal sea conditions and washdowns while still allowing the fuel tank to breathe.
• Can eliminate the need for a separate anti-siphon loop in the vent hose when installed in the correct high location above the tank.
• Removable cover allows access for screen cleaning, vent inspection, debris removal, and fuel system pressure testing.
• Available with black or stainless steel vent head options to match different hull finishes and deck hardware styles.

Variants

This Attwood Marine fuel tank vent is offered in two vent head configurations for the same basic flush mount P-trap application.

The vent head finish changes between variants. Both configurations share the 90° P-trap layout, 5/8" I.D. hose fit, flush mounting style, 1-3/8" installation hole, and maximum 1" hull thickness specification.

• 1674-1, Vent Head Black. The black vent head gives the exterior face a lower contrast look on darker hulls, black trim, or installations where the vent should visually recede.
• 1674-6, Vent Head Stainless Steel. The stainless steel vent head gives the exterior face a metal finish that pairs well with stainless deck hardware, rub rails, and other exposed marine fittings.

Installation and fit

Install the vent as high as practical above the top of the fuel tank and in a location that keeps the vent opening protected from continuous spray, direct boarding water, and hull areas that sit low when the boat is loaded. The fitting should not be placed lower than the top of the fuel tank, since that can allow fuel to escape through the vent line.

The 90° outlet helps the vent hose turn inward immediately behind the hull surface, which is useful in tight sidewall cavities and other areas where depth is limited. Before installation, confirm the 5/8" I.D. hose size, the 1-3/8" cutout, available clearance behind the hull, and the maximum 1" hull thickness.

Use on board

This vent suits small powerboats, fishing boats, center consoles, runabouts, and similar vessels with permanently installed fuel tanks that need a compact flush mount vent. It is most useful where the fuel vent is exposed to rain, washdowns, and occasional spray, but still needs to breathe properly during fueling and operation.

Maintenance and care

Keep the vent opening clear of wax buildup, salt, dirt, and insect debris so the tank can vent freely. During seasonal service or fuel system checks, remove the cover for inspection and cleaning, then confirm the vent hose remains secure, unkinked, and routed upward from the tank as intended.