Hello all, 1987 Catalina 30 Mk II owner. I’m getting a freshwater leak into the bilge when it rains, whose origin I’m trying to track down. Yes, there are a few drips from portholes here and there; but they all have a clear path to get down onto the bilge more or less directly. There is a leak that is coming through the bottom of the bulkhead on its way to the bilge, which has caused some soft wood there. Could it be that rainwater intrusion into the mast is pooling at the bottom, then running down through the deck via the hole through which mast wiring comes down into the boat? How do I confirm this hypothesis, and if confirmed, what crafty options are there to put a stop to this?
Through-mast leak?
- Thread starter LukeAvanti
- Start date
Luke, with water that is s definite, maybe.
You certainly have had enough rain water to expose the leaks. You may need to take your best guess and then try to prove it.
If you have a fair guess as to the source, try to cover the outside area of the source and see if the leak stops. The challenge is you see it at one place, but water has a way of moving through a boat and coming out in a different place from the source.
It you suspect the mast base, then tarp off the area of the mast and see if that "puts the finger in the dyke" stopping the flow. If your mast is deck stepped, you may find that water inside the mast has no way to get out. It should have small holes at the mast base to get out on the deck and return to the sea. These weep holes can become clogged and need cleaning.
Good luck.
You certainly have had enough rain water to expose the leaks. You may need to take your best guess and then try to prove it.
If you have a fair guess as to the source, try to cover the outside area of the source and see if the leak stops. The challenge is you see it at one place, but water has a way of moving through a boat and coming out in a different place from the source.
It you suspect the mast base, then tarp off the area of the mast and see if that "puts the finger in the dyke" stopping the flow. If your mast is deck stepped, you may find that water inside the mast has no way to get out. It should have small holes at the mast base to get out on the deck and return to the sea. These weep holes can become clogged and need cleaning.
Good luck.
A few comments. The front bilge wall on my boat was penetrated by a drain hose from the front part of the boat. So any leak forward of the bulkhead would drain to that bilge front wall drain. I think you may be able to view if water is flowing this route by looking on the aft side of the forward water tank. I had several leaks at stantions ( and any other forward deck penetrations) that I sealed successfully with Butyl tape.
The previous post also details a potential source. There are (should be) drain holes at the base of the mast. However, the mast fits over a deck mounted casting. As dirt accumulates at the base mast interior, the drains become ineffective. It also may be that the rain water is travelling down the mast wiring. The cure here is to add a PVC coupling (or better yet an elbow) as the wires come out of the deck.
Good Luck
The previous post also details a potential source. There are (should be) drain holes at the base of the mast. However, the mast fits over a deck mounted casting. As dirt accumulates at the base mast interior, the drains become ineffective. It also may be that the rain water is travelling down the mast wiring. The cure here is to add a PVC coupling (or better yet an elbow) as the wires come out of the deck.
Good Luck
Hello and welcome,
What you described is exactly the reason I unstepped the mast this winter lay up.
I will put a cover on the mast head, add weep grooves in the mast step base.
The PVC nipple that was epoxied through the deck to accommodate mast wiring has became loose as well as filling in the roughly quarter inch of recess in the center of the step with epoxy
What you described is exactly the reason I unstepped the mast this winter lay up.
I will put a cover on the mast head, add weep grooves in the mast step base.
The PVC nipple that was epoxied through the deck to accommodate mast wiring has became loose as well as filling in the roughly quarter inch of recess in the center of the step with epoxy
