Rainwater leak under cockpit deck

[matts997]

I’ve got an annoying leak under the cockpit deck of my H280, where various cables/wires run beneath the deck (e.g., stern light and shore power wires) passing through a hole to the stern. Image attached. During every Seattle winter, rainwater pools in a depression in the gelcoat under the aft sleeping quarters and collects behind the engine.

I’m not sure how to best repair this. My first thought is to simply remove the old caulk (Boatlife sealant) and re-caulk with 4200, which I’ve read is supposed to have more adhesive than Life seal. Also wondered whether some sort of rubber boot, maybe screwed & sealed in, could work. A friend thought butyl tape might help, but I’ve never worked with that.

Any ideas/suggestions?

 

[LloydB]

Clean off and out as much of the hardened caulking that you can then replace with butyl tape. The butyl tape is not so much tape as it is a long roll of flattened putty and it will not dry up or harden up with time like the caulk has apparently done while leaving a hairline crack for water to flow through.

 

[Hollyberry]

Clean off and out as much of the hardened caulking that you can then replace with butyl tape. The butyl tape is not so much tape as it is a long roll of flattened putty and it will not dry up or harden up with time like the caulk has apparently done while leaving a hairline crack for water to flow through.

Sometimes aka 'Duct Seal'...

 

[dlochner]

That will never seal with caulk or butyl tape. For the many of us who do not have a Hunter 280 could you provide more photos showing the area where the wires enter and the general position.

 

[jssailem]

cables/wires run beneath the deck (e.g., stern light and shore power wires) passing through a hole to the stern.

I understand you believe that the leak starts in the area of the wires passing through a hole. Certainly you are experiencing a lot of rain.

If certain that this hole and degraded caulk is the cause, perhaps it is time to reroute the wires higher up on the panel and seal the lower corner hole of the image area so no pooling water might leak into the boat. You might consider using a Cable Clam to pass the cables through the panel and stay water tight.

https://www.bluesea.com/products/category/23/Cable_Clams

As Dave suggests, More images of the area might help us to better understand your issue.

rainwater pools in a depression in the gelcoat under the aft sleeping quarters and collects behind the engine.

This sounds like the symptom that causes you to look at the above identified cables. Are you certain that their of no other possible deck penetrations that might contribute to this problem. (you tested the theory by running water into the area and finding it in the "depression".)

The evil issue that faces boat owners about water leaks, they can come from multiple sources and sometimes a source you would not associate with the leak.

 

[MaryEllaRose]

Even with a cable clam you’ll still need some sort of sealant between each cable where it passes through the clam.

 

[dlochner]

Even with a cable clam you’ll still need some sort of sealant between each cable where it passes through the clam.

A good quality cable clam, such as the Blue Sea or Scandvik rely on compression of a rubber seal around the wire. They don't leak when properly installed.

 

[Captain Larry-DH]

Even with a cable clam you’ll still need some sort of sealant between each cable where it passes through the clam.

You use one wire with each cable clam. It wouldn’t work with a bundle like that.
I think the only way to stop water from passing through a bundle like that is if it’s elevated, so the water needs to flow up before it flows through.

 

[Tally Ho]

I think @Captain Larry-DH is right….clam won’t seal a bundle like that. I have a similar mess of cables going through the cockpit sole on my O’Day 322, but it is under a “box” mounted on my pedestal. I built up a bit of a butyl tape “wall at the base of the wire bundle, but water could still make its way in if it runs down the wires.

I owned a H280…I am trying to think of where these wires run…in the pedestal thing with the cooler on top?

Greg

 

[matts997]

I owned a H280…I am trying to think of where these wires run…in the pedestal thing with the cooler on top?

Greg

No, the wire bundle passes through a tiny “bulkhead” further aft of the pedestal beneath the cockpit deck (under the helm seat) and adjacent to the radial drive and cables for the wheel steering. It’s below that removable deck panel on H280s that slides out over the swim platform, allowing access to the steering mechanism and cables. See the red circle in the attached diagram. I'm almost certain this is the source of the leak, as the Boatlife sealant I applied 2 yrs ago totally stopped the leak for about a year, but as you see from my first image, it didn’t hold up and cracked.

I don’t think it’s getting submerged in pooled rainwater, but rather rain is coming down directly on top of the bundle through the seam between the removal deck panel and the rest of the cockpit decking. Normally, water coming into this seam runs out the boat’s stern over the swim platform. But the leak occurs when water runs down the wires, through the hole, and down to the bottom of the boat’s interior between the holding and fuel tanks.

I’ll take some better pictures this weekend..and if I have time I’ll remove/clean up the old sealan first. Thanks for all the comments thus far!

Matt

 

[dlochner]

Are there drip loops on the wires? When a wire enters a horizontal opening a drip loop provides a place the water running down the wire from above to drip off the wire before it enters the bulkhead.

 

[Crazy Dave Condon]

Would pressurizing the cabin with a leaf blower brushing the deck with soapy watery to find air bubbling out work here to find the leak?

 

[matts997]

Are there drip loops on the wires? When a wire enters a horizontal opening a drip loop provides a place the water running down the wire from above to drip off the wire before it enters the bulkhead.

Interesting idea. No, there are no drip loops on my wires/cables...I haven’t seen drip loops on a boat before, only on utility lines?

Would pressurizing the cabin with a leaf blower brushing the deck with soapy watery to find air bubbling out work here to find the leak?

I'm pretty confident I have the source of the leak identified--it went away completely when I last caulked it--but the caulk didn’t hold up for longer than a year, so now it’s back.

After thinking more about everyone’s comments, I’m going to next assess whether I can effectively re-route the wire/cable bundle slightly, without having to re-wire everything from the main electrical panel to the source.

Thanks everyone.

 

[matts997]

Finally got back to this and took a view more images of the situation, showing the cockpit with the helm seat and cockpit floor panel removed. As you can see, there’s a drain channel beneath the cockpit floor where water runs down on top of the wire bundle and out the stern & over the swim platform (another one of Hunter’s head-scratching design features).

Wondering what all of you think about using an expandable marine foam caulking where the wire bundle passes though the hole? West Marine sell this:

Sealant Foam Spray, 12 oz. | West Marine

Check out our Sealant Foam Spray, 12 oz. and more from West Marine!

www.westmarine.com

My other thought was finding/re-purposing some sort of metal “tent” or gutter to go over the bundle and screwing/caulking it into the gelcoat above the hole.

 

[dlochner]

Thanks for the photos, they are helpful. I think using any kind of caulking or foam is just another temporary fix.

I count 3 wires and 2 cables in that bundle. Removing the wires from the bundle and using a proper seal will be the best solution.

Remove all the cables and wires, clean up the area and glass the hole shut. Then install a seal like the one below. More work, more likely to work.

Seaview Cable Gland

The Seaview Cable Glands provide waterproof cable routing. These are made of very strong plastic or marine grade 316 stainless steel and come in a variety of colors and finishes. Seaview cable seals fit a wide range of cables and connectors. Features:

www.defender.com

 

[matts997]

Good suggestion and thanks for the link. Discovered that Seaview also makes retrofit seals that can accommodate a cable or bundle up to .39”...it’s possible that installing 2 or even 3 of these would be less work than re-working all the cables/wires. My next step will be to trace where all the wires/cables are going behind the aft bulkhead--it may not be as bad as I think...i.e., to disconnect/re-connect.

 

[Tally Ho]

Good suggestion and thanks for the link. Discovered that Seaview also makes retrofit seals that can accommodate a cable or bundle up to .39”...it’s possible that installing 2 or even 3 of these would be less work than re-working all the cables/wires. My next step will be to trace where all the wires/cables are going behind the aft bulkhead--it may not be as bad as I think...i.e., to disconnect/re-connect.

It looks like the wire bundle goes in to the side of the wall…is that right? Or does it go through the floor?

If it goes through the side wall, your ”tent” might work.

If it goes through the side wall, how close to the “floor” in the hole? If the hole is very near the floor, that is a problem the tent won’t fix.

Greg

 

[dlochner]

It looks like the wire bundle goes in to the side of the wall…is that right? Or does it go through the floor?

If it goes through the side wall, your ”tent” might work.

If it goes through the side wall, how close to the “floor” in the hole? If the hole is very near the floor, that is a problem the tent won’t fix.

Greg

I think the water is running along the cables and leaking through the holes until it drips out. The cables should have a low spot before they enter the side wall, that low spot will prevent the water from flowing along the cable and into the cabin.

 

[Barnacle Bill]

How about getting creative and shielding that mess of cables with some sort of curved plastic or fiberglass cover so that rain water is diverted away from where the cables pass through the vertical surface.? I suppose that won't work if the cables are at an angle where they are angled down as they enter the hole, but if they are straight or angle up, this might work. Even some sort of PVC pipe fitting split in half and then surrounding the cables for maybe 4-5 inches.

 

[dlochner]

Another cable sealing options is a cable gland like these from Amazon. This type of gland will require removing and reinstalling the cables and sealing the big original hole with something. It could be new fiberglass or a piece of plywood properly sealed or a piece of starboard.