Moeller Manual Vent Gas Cap with Gauge, 12.25 Inch, Part 621501-10-1

The Moeller Manual Vent Gas Cap with Gauge (part number 621501-10-1) is a replacement fill cap designed for manual-vent fuel tank systems, built for use internationally and in boats built before 2011. The cap measures 12.25 inches and incorporates a built-in fuel gauge, letting you check remaining fuel level directly at the fill point without removing the cap or checking a separate gauge elsewhere on the tank. As a manual vent design, the cap relies on the boat's separate vent line configuration rather than an integrated pressure-relief vent, making it suited to older tank setups that use this style of fill and vent arrangement.

This gas cap is intended as a direct fit replacement for the fill opening on compatible Moeller-style fuel tanks, restoring a secure, gauge-equipped closure to the fuel system. Because it is rated for international use as well as pre-2011 boats, it suits both older domestic vessels and boats operating under non-US emissions requirements.

Specifications

• Brand: Moeller
• Manufacturer Part Number: 621501-10-1
• Product Type: Manual Vent Gas Cap with Gauge
• Diameter: 12.25 inches
• Vent Type: Manual vent
• Gauge: Integrated fuel level gauge
• Weight: 0.1 pounds
• UPC: 808282390686
• Category: Gas Caps and Deck Fills

Fitment

• For use internationally and in boats built before 2011

Frequently Asked Questions

What is the Moeller 621501-10-1 gas cap used for? The Moeller 621501-10-1 is a manual vent gas cap with a built-in fuel gauge, used to close and monitor the fuel fill opening on compatible manual-vent fuel tank systems.

Does this cap fit boats built after 2011? The Moeller 621501-10-1 is designated for use internationally and in boats built before 2011; fitment on boats built in 2011 or later is not specified.

What size is the Moeller manual vent gas cap? The cap measures 12.25 inches across, corresponding to the fill opening it is designed to close on compatible tanks.

Does the cap include a fuel gauge? Yes, part number 621501-10-1 is a cap with an integrated gauge, so fuel level can be checked directly at the fill point.

Is this a manual vent or a pressure-relief vent cap? This is a manual vent design, meaning it relies on a separate vent line in the boat's fuel system rather than a built-in pressure-relief vent.

How much does the Moeller 621501-10-1 gas cap weigh? It weighs 0.1 pounds.

Is the Moeller 621501-10-1 suited to international use? Yes, this cap is designated for use internationally in addition to boats built before 2011.

What is included with the 621501-10-1 gas cap? The product is the manual vent gas cap with gauge itself, part number 621501-10-1.

How do I know if this cap will fit my boat's fill opening? Confirm your existing fuel fill uses a manual vent tank system and a 12.25 inch opening, matching the dimensions of the Moeller 621501-10-1 cap.

What category of part is the 621501-10-1? It is classified as a gas cap and deck fill component for marine fuel tank systems.