A tiny bulkhead hole allows pressure equalization. Very tight compatments can blow covers when crossing Mt. passes etc. Foam bulkheads have even shifted in boats with Valley hatch covers.
Now, take a hot boat from your car and drop it in 45 degree water. Hatches suck down right? Yep, and that's no big deal other than the compartment is now in a vacuum state. Any micro cracks etc now have water being "sucked" into them so to speak. Weird very minor nagging leaks have been cured by relieving this suction. Burping is smart, but pressure changes happen even when on the water.
I have done this for years and recommend it. There's no downside that I can see.
Even smaller stuff… … like waves breaking over a sun heated deck - can cause water to suck in around some hatch seals and such. Doesn’t happen if vented.
Still haven’t gotten to mine yet - but when water and air are both 90 degrees and you live very close to sea level, there aren’t much if and pressure changes and seals remain soft, so things like this can slide…
Hole should be more centered… … to avoid this rolling/inverted issue. Did it come this way from QCC? Mine came unvented, but that was like 6 years ago.
Do you have skeg or rudder? I don’t know how they do the rudder tubes, but if they’re still doing the skeg tubes the same way you’ll get part of a skeg box full of water draining into in the rear compartment on every roll. Before noticing this I’d been blaming the hatch covers. I redid mine so there is continuous tubing running from box to bulkhead now and the compartment stays pretty darn dry now after multiple rolls.
Ahhhh, I think I understand CD1 has taken the suggestion from “his outfitter” at Geneva Kayak to drill the hatch covers on his sectional Valley Aquanaut and tried to universally apply the same logic to venting the compartments on one piece boats.
Seriously dude, more paddling and less blathering of confused, misinterpreted and unfounded “advice” on P.net.
that would be my Explorer My hatches are extremely air tight. I forgot to take them off and drove from sea level up to Asheville, NC. When I stopped for gas and checked my kayak I noticed that not only were the hatches bulging outward, but the deck was also bulging outward.
Fortunately I haven’t noticed too many bad side effects to my deck.
Yep … came that way from QCC … … but, as I mentioned, the boat was upside down frequently, with me out of it, and for sometimes prolonged periods of time. All things considered, the relatively small amount of water that got through wasn’t an issue (to me). I can’t roll (yet) and during a real assisted or self-recovery I can have the boat uprighted in a very short period of time so I imagine the amount of water that would get in there could be measured in teaspoons (or less).
I suppose they put the hole up that high so it wouldn’t get blocked/closed by a dry bag or something else when packing it for camping, unless you’re stuffing the entire compartment all the way to the top!
And … it does have a skeg … … with continuous tubing shielding the wire from the skeg box through the bulkhead so no water is getting in through there.