Bought a 1988 204 Fisherman center console, got it in the water Manhasset Bay mid August (by the time DMV got reg done). "Neighboring waters" looks like from your avatar Northport?
Powered with a Honda 150 4 stroke along with 2 batteries put the scuppers just below waterline. Bilge hatch is somewhat sealed and has old pop out access port which i'll be replacing before next season. Kept the boat docked, and every time before we launched i'de flip the manual bilge pump switch to drain out whatever water accumulated. Theres always about an inch of water covering the access hatch. Quickly got out of the habit of plugging the flapper scuppers after last plane when I was home, it was pouring, and I was asking myself: Did I leave them plugged or not due to pending rain, lol.
Sounds like we have the same boats & yes that is the Northport lilco stacks in my avatar.
I got my boat in June boat & it has mostly kept it on a trailer for years. Regardless Im certain we both have some moisture in the transom plywood & that adds water weight. I think a little is better than a lot in this case. It's just the age & design of the hulls. Mine does not seem terrible & I know its been used on & off a trailer for quite a while. Hope yours is a drier boat as well & hope mine is as dry as I hope. Lol, that said.... still a great fishing boat.
an old trick is to drill a hole low on the transom & one at the top. Leave it all offseason at the very least. See what comes out the bottom hole. A hot sunny day will aid in this by heating the moisture enough to increase any seepage. You will see some most likely. Epoxy will plug these holes quite well & the epoxy drives moisture back when it cures so the holes will seal well. Just plug the holes on a cloudy or cooler day. I had a whaler for years & most older ones have some stage of wet transom. It can be inevitable.
i did some research online & came across some pics of a similar boat with the waterline painted straight through the middle of the scuppers. I’m sure across the that is the correct location & the evidence of an actual water line of the one i saw looked to be right at the bottom of the scuppers as well. I think that was a 204c overnighter though & they look to have much more bow weight than ours due to the cabin structure. That probably always caused the 204 fisherman to sit ass low. Same hulls, different centers of gravity.
Mine came to me painted across the top edge of the scuppers, actual waterline at rest with a full tank is right at the painted waterline. So I keep the plugs in mostly but not when fishing. Lol, boots required. I also have now sealed down the hatches & replaced the round plates with new sealed screw down type. The deck must be sealed at the floor hatches.
The drains are large diameter, 1-1/4”. If the bilge stays empty the boat stays buoyant & the floor will wash out as it lowest point, at the stern. If you’ve ever seen an old wooden fishing vessel they used a wash deck like this too. It’s an age old design. Just keep the over wash out of the bilge below as it adds weight & the small pump can’t compensate for too much Water coming over the back in snotty seas.
Now for the scuppers themselves. I purchased a set of the flapper type. I then after looking at them & reading others opinions decided to go ahead & get the ball types instead. I understand that the ball type keeps a lot of the nuisance back flow through the scuppers out when at mooring. The flaps will inevitably fail to seal well & the boat will stay wet due to that.
i ordered the good ones though, I hope. I opted for the flow master ones that have a two piece design that allows for them to be easily removed. This is important for hosing out the boat on the trailer & keeping leaves from collecting in the drain tubes. After all a boat on a driveway is nothing but a large gutter most days. If I can leave them off at home the leaves wash right out too. Also when docked for the season you can take them off to clean the scum off from time to time or they will begin to clog in no time. Toss the crab legs over board & off the floor too. Lol, my buddy likes to bring potatoe chips fishing & they’ll clog the ball types. Keep them cleaned out & they should work as designed.
The boat is designed to take wash either over the bow while under power or over the transom perhaps while drifting in rough seas. It will, in theory, wash immediately out the four transom large scuppers. The floor needs to be sealed tight for this to work correctly. Rain water washes out as well.
The previous owner gave it to me with the hatch loose & unsealed, with four plugs in the scuppers. that’s just not good idea with this hull design at all.