Tomcat fish box filling up?

[Westie]

Hi,
I have a 2006 Tomcat and I've noticed that the starboard fish box fills up with water; port side is totally dry. I know this particular boat leans a bit to starboard but I have balanced the cargo so it's not even noticeable. It seems the valve just above the water line isn't preventing inflow. Any thought on how a could be remedied without replacing the valve? If I need to replace, is that easy to do?

Thanks

[rogerbum]

I'm uncertain about what "valve" it is that you're speaking about. Do you mean the nearby scupper?

[Westie]

Yes - I mean the scupper. It seems very stiff.

[Discovery]

I have had problems with the fishbox pump-out lines taking on water when I launch and load from the trailer. To fix the problem, I put rubber corks in the discharge holes on the outside. Blow back through the line to determine which ones are the fishbox's so as not to plug the bilge discharge lines. The fishbox's are best suited for wet storage only. When heavily loaded cruising, I also plug the deck scuppers with plumbing clean out plugs, but from the inside. This keeps the deck from taking on water with a stern heavy loaded boat.

[gulfcoast john]

Hi Westie!
Mine has 3 aft through-hulls on each side. The lowest (with a rubber flapper on the outside) is the passive cockpit scupper drain, which makes a 90 degree flat turn. The other 2 output the bilge pump and fishbox macerator pumps. If a big guy stands in the aft corner he may put that scupper far enough underwater so that seawater can flow into the cockpit oozing past the flapper (but it has no direct connection to the fishbox drain). I consider it good practice to stick the garden hose in the drains from the inside to flush em out, since a lot of cockpit debris, leaves etc all gets washed down there, esp at that 90 degree turn, and ensure no debris is holding the flapper open. It's easy enough to replace that scupper assembly from the inside, although it won't do any good if the real issue is the drain is too close to the waterline. If they used 5200, you’re hosed. Some owners plug the inside cockpit scupper with a stopper when having heavy company at the dock or launching like Brent. Not advised when underway. I've never had that issue so far (Triton hull #0001) though I did buy the stoppers. I read that the starboard listing issue was addressed by moving the 30-gallon water tank to the slightly forward port sponson (that’s where mine is).

The fishbox drain is plumbed to a macerator pump on each side, with the output sent up a loop and overboard when the pump is turned on. Any water in the fishbox can't get past the pump until the pump is turned on (there is no fishbox float switch unless the owner installs one, and fish would crush it or clog it). Seawater can’t enter the fishbox macerator pump thru-hull due to the loop being within an inch of being as high as the sides of the cockpit. If seawater is coming in over the side of the boat that way, you have a lot more of a disaster than water in the fishbox.
Cruisers disconnect the fishbox hose/clamp where it enters the macerator pump and let that end lie in the bilge, so that errant rainwater that gets in the fishbox drains into the bilge and gets pumped overboard by the automatic bilge pump/float switch, also through an upper loop (did someone do that on your port fishbox?). That way the fish boxes stay drier (not dry) and our rear anchor, lines, fenders, hoses and other stuff we store in the fishboxes stays drier. If you never, ever put fish in the fishboxes that's a good solution. But you wouldn't want fish scales etc to drain into the bilge.
Despite the gaskets and cockpit scupper drains all TC255 fishboxes seem to suck down rainwater or any other water by capillary action, or perhaps by magic.
Good luck!
John

[BTDT]

[rogerbum]

In a strange way, I kind of like the fact that one can't keep the Tomcat fish boxes dry. It was a snarky comment I made on a thread about this 5 years or so ago that wound up connecting me to the seller of my current Tomcat. So if the fish boxes stayed dry, I probably wouldn't have the current boat. The bottom line with the fish boxes are that they are not properly designed. If you look at the boxes on many other boats (for example the Skagit Orca), what you find is a much deeper "trough" around the outside that extends to the scuppers. E.g. the trough is deep enough so that when water enters, it drains through the cockpit scuppers instead of into the box.

With a good bit of work, one could re-do the fiberglass on the deck around the fish boxes to create a deeper trough. However, the cockpit drains are not that far above the water line so it would be better to drain the trough into a sump system with a separate bilge pump. Then the boxes would stay dry.