Are you sure it is the midship hatch and not the front Orbix hatch that is leaking? The front Orbix hatches are notorious for warping and leaving a gap at the front and rear.
The only problem I've had with the midship hatch is when I get the cord caught between the lip and the hatch, preventing the hatch cover from sealing tight.
I'm 100% positive that it is the midship hatch, i usually carry a picnic blanket and i'ts usually dry with only a few drops of water seeping through when water flows over the Orbix hatch in light rapids. The problem is that when going through large rapids the cockpit fills up and i sit in water that covers the 6" hatch for up to about 10 seconds at a time. The cat bag is always full of water.
I found out that you can put in another hatch by cutting off the lip that holds the hatch in place. This is not really desirable. Have you had a similar experience? Do you think i should get another rubber cover and will it make any difference? The cover i have on is not really that tight.
The closest kayak shop is about 600km away and i make always check that the the cord is not pinched.
This Saturday when i took her out i sealed the hatch with a plastic bag and elastic band and put the hatch-cover over that. Our rivers are currently experiencing some heavy flooding so we are getting some great rapids. There was a section of about 200m where the wave train caused the hatch to be underwater for about 20 to 30 seconds. At the end of the trip there was a minimal amount of water in the hull, so it's safe to say the problem is with the hatch-cover. I have acquired a new screw-on hatch that fits on top of the lip over witch the rubber hatch-cover folds. I'll replace the old hatch and take it for a spin and i'll let you know how it works out.
how did it work out?
I completely stopped the leakage from the middle-hatch but unfortunately water still fills the kayak from the front hatch. I've tried fixing the front hatch with rubber but cant seem to stop it filling with water in rapids. I've actually given up and just got some extra dry bags.
That said the water inside was reduced significantly, depending on the amount of rapids we do on a day.
Thx, dealer got me a new hatch, waiting to get installed. looking to make a spray skirt or diverter since I never access front hatch on the water.