Water inside the Deck floor

[Rees]

I've been attempting to stop the water that leaks into my boat from above when it rains.  I replaced the saloon hatch, caulked chain plates, R & R'd the deck vents and have gone over my mast boot several times with 3M sealant adhesive. Even with all this effort I am still finding water all around my mast and (sometimes) on my nav table which is below one of the deck vents.  Water from these two areas now seems to have a common theme; it appears to be leaking out from between layers of the deck above and the cabin ceiling. I can see what appears to be a crack parallel to the deck inside the hole that the mast passes through as well as the hole that makes up the vent "though-hole(?)"  I have placed a moisture meter on the ceiling in various places on the saloon and galley ceiling to find high moisture readings mostly on the starboard side of the boat near the galley.  I cant for the life of me figure out how water is getting into this area, but as I mentioned previously, I see regularly indications of water exiting through these apparent cracks between layers. Is there anyone out there who has dealt with this problem or with knowledge of the inner workings of deck construction to know what is going on between my deck layers and how water might be getting in there?

[Noah]

I don't understand the first photo. Do you have one taken farther away to give some context as to what we are looking at?

[Dave Spencer]

Noah,
It took me a minute to figure out the top picture but I now see is as an extreme closeup looking up the mast at the partners from inside the boat.  The four arrows point to voids between the interior liner and the deck.  The inside of the mast boot can just be seen between the deck and the mast.
I don't know what the "vent through hole" is though.

[Ron Hill]

Rees : How about your hull # and production year!!

I believe that you have syced out your problem. Could the water be coming in from one or both of the deck organizers ??
Is this water intrusion happening now AFTER you installed a new center hatch??

A thought

[waughoo]

We shall have the OP confirm, but I suspect the vent through hole is at the dorades (assuming a mk1).  If you are seeing isolated moisture readings in the headliner at the galley, I would look for deck hardware above that area... traveler, dorade boxes, aft end of the handrails, sea hood mounting, sliding hatch teak rails etc...