Issue 128: Sept/Oct 2019
A New Approach to Through-Hull Redundancy
Given that I needed to change the ball valve on the through-hull for my AC raw-water intake, I was the perfect candidate to test this better-mouse-trap device intended to replace the time-tested tapered wood plugs we keep in case of a through-hull emergency — only this isn’t what I did, not at first.
When the ball valve came off, and water gushed, the first thing I did was push the tapered wood plug into the 1-inch hole. We were no longer sinking, but things were at an impasse. With the plug in place, I couldn’t screw a new ball valve onto the through-hull. I knew the Sea Bung I’d been sent promised a better outcome.
In short, the Sea Bung is a mushroom-shaped piece on a long stick-like stem. The mushroom part collapses as it’s pushed through a hole (it’s made of thermoplastic polyurethane) and then opens back up on the water side and takes advantage of head pressure to stop the inflow.
It was time to try it. I pulled the wooden plug out and quickly shoved the Sea Bung straight through the through-hull. Water pressure pressed it against the outside flange of the through-hull fitting and the inflow of water stopped immediately, totally.
After cleaning the threads of the through-hull fitting with a wire brush, I applied a sealant to them before sliding the new ball valve down the stem of the Sea Bung and screwing it on. Then, I pulled the Sea Bung back out of the through-hull and quickly closed the ball valve.
I don’t have any complaints or critique of the Sea Bung. The package included two bungs, a small and a large (I used the smaller one). A feature I didn’t use is the ring molded into the top of each stem. This is a tie-down point for a string or cord that could be used to apply and keep tension on the Sea Bung, in a case in which the through-hull is too close to the surface to provide adequate head pressure.
Sea Bungs are made in England and more information can be found at: seabung.com — Roger Hughes, Good Old Boat contributor
Open Anything
The Mantus Marine Universal Deck Key is a winning combination of several boat-specific tools in one. It’s forged from stainless steel and has a different form factor than other deck keys. One part of the key slides on the other, creating a spanner wrench that is adjustable up to four inches. I successfully tested the key on several slotted, keyhole, and finger-twist deck plates. I tested the shackle-opening slots on several stubborn shackles of different sizes, and the key provided plenty of leverage to open them easily. There are four hex wrenches on the tool (7⁄16, 11⁄32, 3⁄8, and 5⁄16) and a key for opening octagonal-starred deck fills. And rest assured, there is a bottle opener. For some reason, there is no tool for opening hexagonal-starred fills (common on Beneteaus). Mantus was interested to learn of this omission when I called them; maybe something we’ll see in the next version?
For more information: mantusmarine.com — Jerry Thompson, Good Old Boat contributor
Thank you to Sailrite Enterprises, Inc., for providing free access to back issues of Good Old Boat through intellectual property rights. Sailrite.com
