VENTED DECK FILLS

Attwood Angled Vented Deck Fill Model # 3682
Perko Combination Fuel and Vent Set Model # 1319
Perko Combination Fuel and Vent Set Model # 0541
Seacurefill Fuel Recovery System 1 ½” Model
Vented Deck Fill Summary

If your boat doesn't already come with a vented deck fill installed, be prepared to cut into your deck to accommodate one. It also must be located away from an area that can get substantially flooded, as the vent in the cap must breathe air.

Combination deck fills and vents, or vented deck fills, literally combine the fuel vent (that usually vents overboard) with the deck fill. Essentially, the vent line is redirected into the neck of the fill allowing vented fuel to return safely to the tank. When these units are installed at the factory, there is no need for an overboard vent. However, if you choose to install one of these devices yourself you must seal off your existing overboard vent so that water does not condense or siphon into your boat.

You may also have to cut a slightly larger deck opening to accommodate this larger fixture. This new unit allows for movement of air into and out of the tank via the cap and essentially functions as a vent when not refueling. For this reason, vented deck fills are not air tight, and therefore are NOT watertight.

Both Attwood and Perko specifically bring this trait to your attention and urge you not to install this device in a location that can become substantially flooded or submerged. The Seacurefill device uses your existing vent and functions somewhat differently so water intrusion is not a problem with this unit.

Above: ATTWOOD ANGLED VENTED DECK FILL (Model #3682)

Above: ATTWOOD ANGLED VENTED DECK FILL (Model #3682)-- OPEN

ATTWOOD ANGLED VENTED DECK FILL (Model #3682; retails for $59.99). The Attwood Angled Vented Deck Fill features a hinged plastic cap and a stainless filler neck with an integral vent and splash guard to prevent spills. The angled neck of this model allows for various installation orientations, including an angled surface. We chose to mount it on a 45 degree angle which allowed for good visibility to see the internal vent (which is inside the filler neck) when refueling. This gave us the comfort of looking around the inserted nozzle for hints that the tank was nearing capacity.

During our mock-up test, with the nozzle fully inserted and pumping at both 10 gpm and 20 gpm, fuel managed to back up the filler pipe and trigger the auto shut-off on the pump nozzle too late. At 10 gpm, the splash guard managed to redirect most of the fuel back into the tank, but at 20 gpm, fuel worked its way past the guard and ended up on our deck. Since the unit was mounted on a 45 degree angle, the vent was actually slightly higher than the fill opening and we wondered if this characteristic contributed to the auto nozzle clicking off too late.

On the plus side, its built-in plastic splash guard minimized “misting,” which occurred on other models when vented fuel bounced off the nozzle, keeping the deck essentially dry until the tank became full. This unit requires a grounding wire to prevent sparking when a nozzle is inserted, so please refer to the instructions for safe installation. The Attwood deck fill and can be ordered through the BoatU.S. and West Marine catalog sales special orders department.

Above: PERKO COMBINATION FILL AND VENT SET (Model #1319)

Above: PERKO COMBINATION FILL AND VENT SET (Model #1319)-- OPEN

PERKO COMBINATION FILL AND VENT SET (Model #1319; retails for $20.99). Perko offers many styles of vented fills for gas, diesel and water. The model we tested was a black plastic deck fill with a hinged “flip top” opening that did not require a deck key and was clearly labeled “gas.” Because it was hinged, the lid could not roll into the water but we did worry that when open, someone stepping on it could break it. Since this model is all plastic, no special ground wire was required.

Because of its hinged design, there was no beaded retainer chain for the lid getting in the way of visibility into the neck of the deck fill. When the fuel tank was nearly full, we could easily see that the vent was doing its job by redirecting vented fuel back down the filler neck during the refueling process. As in other tests, we waited for the auto shut-off device to disengage. Unfortunately at both 10 gpm and 20 gpm testing, fuel spilled out of the filler neck suddenly just as the nozzle clicked off and flowed onto the deck. We also found that the larger nozzle (delivering 20 gpm) did not fit very well in the deck opening and we experienced slight misting on the deck during the fueling process as a result of the vented spray hitting the nozzle and landing on the deck.

This unit and other Perko models can be ordered through the BoatU.S. and West Marine catalog sales special orders department.

Above: PERKO COMBINATION FILL AND VENT SET (Model#0541)

Above: PERKO COMBINATION FILL AND VENT SET (Model#0541)-- OPEN

PERKO COMBINATION FILL AND VENT SET (Model #0541; retails for $28.99). This Perko product featured a round polished chrome cap and a plastic body. The cap has a beaded stainless steel retainer chain which is attached to th e inside of the neck, making a snug fit for the nozzles. The tight fit blocked our view of the vent, so we couldn’t observe the venting process as it occurred. Additionally, the tight fit caused misting on the deck as we noted with other units, especially at the higher velocity. A ground wire is NOT recommended on this unit because of its plastic body and the possibility of an electrostatic discharge.

During testing, we experienced results similar to the other models previously tested. At 10 gpm, the tank would suddenly become full and backsplash would spill out of the deck fill just as the automatic shut-off nozzle disengaged. And at 20 gpm, even more fuel flowed from the deck fill and onto our deck. This unit can be ordered through the BoatU.S. and West Marine catalog sales special orders department.

SEACUREFILL FUEL RECOVERY SYSTEM (1 ½” Model; retails for $139.00). The Securefill is a different kind of vented deck fill. Instead of having an integrated vent, it requires you to permanently install a new vent fitting in the deck adjacent to your existing deck fill. It works by redirecting the vented fuel back into the original deck fill via a piece of clear vinyl tubing that you must attach temporarily each time you fill up your boat. The concept is simple - the clear tubing literally allows you to see the venting process during refueling so you will react and slow down in response to the rising fuel bubbles.

To install, you must cut a hole in your deck about the same size as your existing deck fill. You do not have to abandon your existing vent, but below deck, you will need to fit your existing 5/8” vent tube to a nipple on the bottom of the unit and add another short section from the Seacurefill unit to the existing overboard vent. This allows for the boat’s vent system to breathe and operate normally when not refueling.

Above: SEACUREFILL FUEL RECOVERY SYSTEM (1 ½” Model)

Above: You do not put fuel in the Securefill unit although it looks like a regular deck fill. A different color cap is now offered to prevent potential confusion, especially when someone else, like dock staff, refuels your boat.

Above: The Seacurefill temporarily bypasses your existing vent during fueling. It is fully restored after you replace the cap on the Seacurefill unit and your deckfill.

We tested this device as we did the other units – at both 10 gpm and 20 gpm and pumped until the handle clicked off. In a way, this was an unfair disadvantage since this unit relies on you “seeing” the venting process so you can react by slowing down. Regardless, we carried out the test as planned using the standard “control fill” and found that that this unit allowed the nozzle to click off just in time (we could see fuel rising in both the clear tube and fill level) with minimal spilling at 10 gpm. For the 20 gpm delivery, we saw fuel enter the tube but fuel rose too rapidly for the automatic shut-off nozzle to disengage, spilling out a few ounces onto the deck. Seacurefill does make a 2” model that we suspect would better accommodate larger nozzles and higher delivery speeds. The Seacurefill Fuel Recovery System can be purchased at BoatU.S. and West Marine stores and through internet and catalog sales.

Above and Below: The vented deck fill is a good concept, but we only recommend these products if you use them with caution.

Vented Deck Fill Summary:
The vented deck fill is a good concept, but we only recommend these products if you use them with caution. The vented deck fills did not promote backsplash as much as some of the inline separators did, but we were surprised by the fuel that found its way onto our decks. In general, these devices have a slight advantage over the inline separators: if you move the nozzle over to one side, you may be able to see when the unit begins to vent into itself and slow your speed of fuel delivery. The Seacurefill gives the most visible cues since clear tubing allows you to see precisely when your tank begins to vent, signaling your tanks are full.

In general, we found that while refueling at 10 gpm, the amount of fuel from the venting process wasn’t significant enough to trip the auto shut-off fuel nozzles. Many times, the auto-stop feature disengaged just as the fuel reached the top of the deck fill, so the spills were contained to only a few ounces. However, none of the devices tolerated the high-speed fuel delivery at 20 gpm and sometimes spilled as much as a cup or more from the deck fill. Fuel would often continue to gurgle up and onto the deck, even after the nozzle clicked off. Additionally, because these deck fills have integrated vents, the nozzle opening was snug which made them prone to misting the deck with fine droplets of fuel.

As with the inline separators, we’ve learned you should never rely on the auto-stop nozzle triggering off in time. You will want to use an absorbent fuel collar, bib or pad to catch droplets, but do keep in mind this will restrict your ability to see what’s happening in and around the vent area. Also, always fuel slowly as you reach the top of your tanks.