Perko 1270 Style Replacement Deck Fill Cap, O-Ring, Retainer

Overview

The Perko 1270 Style Replacement Cap is a polymer replacement cap for Perko Figure No. 1270 fuel and water deck fills. It is made for boats that already use the 1270 fill style and need a correct replacement cap for gas, diesel, or water service.

This cap range is non-vented and includes the matching cap type marking, so the deck fill remains easy to identify during fueling or water fill-ups. Each configuration is supplied with an O-ring and retainer, which helps keep the cap sealed and attached at the fill point during normal use on deck.

Key features

• Polymer cap for Perko Figure No. 1270 fuel and water fills.
• Available in gas, diesel, and water versions so the cap marking matches the deck fill service.
• Non-vented 1270-style cap for use with the correct matching fill and system layout.
• Includes an O-ring and retainer for a proper cap replacement at the deck fill.
• Practical spare for boats where the original fill cap is worn, missing, cracked, or hard to secure.

Variants

This replacement cap is offered in multiple configurations for different fill services on board.

The service marking changes by variant, while the 1270 replacement cap style, polymer cap construction, O-ring, and retainer remain consistent across the range.

• 1270DPG99A: Gas cap. This version is marked for gasoline deck fills and should be matched only to the appropriate Perko 1270 gas fill, not to an EPA-compliant sealed fuel system.
• 1270DPD99A: Diesel cap. This version is marked for diesel deck fills, helping separate fuel types clearly at the deck fitting.
• 1270DPW99A: Water cap. This version is marked for water fills, making it easier to distinguish potable water access from fuel fill points.

Compatibility and fit

Use this cap only as a replacement for the Perko 1270 fill style. The part should match the existing cap type on the boat, including the service marking and the non-vented configuration. For gas installations, confirm that the vessel uses the compatible non-EPA fill style before replacing the cap.

Installation and use

Installation is straightforward when the existing deck fill is already a Perko 1270 style. Remove the damaged or missing cap assembly, check that the fill neck and sealing surface are clean, and fit the replacement cap with its O-ring and retainer in place. A clean sealing surface matters on deck, where spray, washdowns, fuel residue, and dirt can affect how the cap seats.

Use cases on board

This cap is a good match for boat owners, service yards, and marine technicians replacing a lost or worn cap on an existing Perko 1270 deck fill. It is especially useful as a spare aboard cruising boats, fishing boats, and workboats where a missing fill cap can quickly become a water intrusion or contamination problem.

Maintenance and care

Rinse the cap area with fresh water after saltwater exposure and check the O-ring periodically for wear, flattening, or cracking. Replace the cap if it no longer tightens correctly, if the retainer is damaged, or if the service marking is no longer readable.

What’s included

• Replacement cap
• O-ring
• Retainer