use vacuum! water under a vacuum boils at a lower temp. this will speed up the drying process. get it out now rather than later. if you can't borrow a pump from a boat guy try an ac tech or appliance guy. they use them to remove the moisture in ac systems. use west systems to repair the hole. making it a little bigger will make it easier to repair. ie 1/2 hole use 1/2 inch dowel to fill it. don't go all the way through or you will have to plug it on one side to hold a vacuum.use a gauge to make sure it dosen't leak

might already have to plug from inside - he mentioned that he found water creeping into the bilge...

I just edited post #8. The screw hole does not go all the way through. So the water from that hole wicked through the transom to some undetermined hole inside my bildge.

Fresh water or salt water ?? Vacuum Pump or a larger hole for evaporation..your only choices...

The last really dripping wet one I did took about a week for the Vacuum pump at 20+Hg to get it where there was no water dribbling into the large catch bottle I had coming from the transom..an Outboard Transom
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I patched the holes and it is still good to this day.

on a personal note I believe it is near imposable to dry the thing completely and there is the problem.

As we know the wood =food source with the natural fungus and such always present so to complete natures recycle recipe.... just add water.

But if sea water is the culprit with Some woods salt water preserves them well..others not so lucky..

Just make sure you get as much water out as you can before patching.

Plywood is its own worst enemy in this condition..with the ply orientation well I mean nature's little water pumps slowly move water a long ways in all directions.

so acting quickly is your only choice.

Steve 1, thank you for replying to my PM.

It was fresh water. What about forcing bleach into the hole to help kill the rotting process before starting additional drying processes?

If I drill a 1/2 hole all the way through, I'll probably have to pull a engine to patch it on the inside. Something i'd like to advoid, as I've already pulled a engine twice this summer.:mad: The drain plug is close to the screw hole, about even with it. (see picture). I'm thinking about pulling the plug assembly out, and used the heat and desk fan through it, along with enlarging the screw hole to 1/2 inch, but NOT going all the way through the transom.

This is a well-made boat by 1985 standards. Would the plug assembly hole be sealed before the plug assembly was installed? In other words, if the plug assembly was pulled, would there still be some kind of water-proof bearier(sp?) preventing moisture from escaping through the plug hole?

Sorry about the blurriness of the picture. The screw hole is about 2 and a half inches from the drainplug hole.

You may of got a little lucky there and the water migrated thru too the transom drain then into the bilge..

Yes the drain plug hole would be good access and chances are it was sealed with laminating resin. which is working against you now.by keeping the moisture in.

like i said try to get all the water out you can if you plan on keeping the boat.

The other thing with the guys up north is the freeze-Thaw cycles during the winter that does not help to keep a tight transom.

Another thing that hole is close to the bottom maybe with the heavy bottom Lamination and the over-lap from the transom lamination.

you could maybe be below the Wood ...in the old days we used some paste around the perimeter of the transom core Also and set it in wet Mat before clamping and maybe the Screw hole is in an harmless area like that.

Seal all of the holes and use a GPS for a speedometer.

I wouldn't think you woudl want the pitot so close to centerline on a single. This must be a twin engine boat.

Use a vacuum pump it is the only way to dry it out in a hurry. A fan will only dry out the water on the surface not what has soaked into the wood. Fix it right now or replace the transom later.( BIG JOB ) See if you can get a pump and drill the hole bigger and fit a hose just into the fiberglass and seal it to the gel coat. fix the hose into a large glass bottle -- the kind bottled water used to come in -- have two tubes going into the bottle top and seal it up ( cork or rubber plug works great) -- one tube goes to the hole in the transom the other goes to the pump. This will make the pump last a lot longer since the bottle will trap the raw water. I doubt that you will be able to create enough vacuum to boil water at room temperature pulling moisture out of a transom. Let the pump run for a few days -- check the bottle oftener and change the pump oil every few hours. Too bad you don't live closer - I have a good used one that I would let you borrow.