Deck fillers

In the Cap Screws product group, you will find cap screws for installation in fuel and water tank filler openings: a cap screw made of chrome-plated brass with the Fuel marking, a 38mm GAS cap screw with a lock, a cap screw with an O-ring 36mm, a red fuel cap, a cap screw cap in red, and a Roca cap screw without a cap 38mm made of stainless steel.

A deck filler is a filler opening installed on the deck, from which fuel, water or other liquid is filled directly into the tank without having to take the filler hose all the way inside – this is safer and more practical, especially with fuel, as the vapours cannot collect in the cabin. The marking (such as "Fuel" or "Gas") is an important safety feature that prevents the wrong liquid from being filled into the wrong tank – this confusion can be dangerous if, for example, fuel ends up in the water tank. The lockable design prevents unauthorized access to the tank and reduces the risk of theft in port. The O-ring is a consumable part that should be checked and replaced regularly, as a worn or hardened ring no longer seals the filler opening watertight, which can allow salt water into the tank. Always check the diameter and thread of the filler before ordering to ensure that it fits the existing installation opening.

The color of the cap on the filler neck (red for fuel) is a standard practice that helps you quickly identify the correct tank, even in the dark or when refueling in a hurry – this color coding should also be followed when changing the cap to avoid misunderstandings. The size of the O-ring must be precisely matched to the diameter of the cap; a ring that is too loose will not seal, while one that is too tight may prevent the cap from being screwed on properly.

It is worth checking the surface of the lid around the lid screw regularly for cracks, as a possible leak around the screw is difficult to detect until damage has already occurred to the lid structures. Roca manufactures high-quality, long-lasting screws that can withstand repeated refueling for years.

The markings on the deck screws (Fuel, Gas, Water) are internationally recognizable, which makes refueling easier even in foreign ports.

Replacing the O-ring on the cover screw is a simple but important maintenance measure that should be done every few years as a preventative measure before the old ring starts to leak. Roca manufactures screws in several different diameters, so accurate measurements before ordering will save you from unnecessary returns.

Roca brand screws are widely compatible with the standard mounting holes of many different boat manufacturers, making it easy to find a replacement part.

Fast delivery

For products in stock, 1-3 workingdays. For ordering products, 2-7 days.

Customer service

010 548 5605 (days 9-18) asiakaspalvelu@marinekauppa.com

14-day right of return

Products have a 14-day free return right. All products have a minimum 6 month warranty.

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CONTACT INFORMATION

Our customer service is available on weekdays 9-17.
email: asiakaspalvelu@marinekauppa.com

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Deck fillers group products

Deck Filler Body Cap, red

Deck Filler Body Cap, red

Roca Deck Filler Body without Cover 38mm

Roca Deck Filler Body without Cover 38mm

Deck Filler Body with Lock 38mm, gas

Deck Filler Body with Lock 38mm, gas

O-ring for Deck Filler 36mm

O-ring for Deck Filler 36mm

Fuel Cap, red

Fuel Cap, red

Fuel Deck Filler Body, chrome-plated brass

Fuel Deck Filler Body, chrome-plated brass

Perko Fuel System Locking Cap

Perko Fuel System Locking Cap

Osculati Universal Deck Filler Key, stainless steel

Osculati Universal Deck Filler Key, stainless steel

Osculati Deck Filler Key

Osculati Deck Filler Key

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