Deck leak to raw water intake area

[Mick Laver]

This one is driving me nuts. After any kind of substantial rain fresh water collects by the engine raw water intake through-hull. There is no drain hole to the bilge there (yet!) so there's no where for the water to go. For the life of me I can't figure out where it would be coming from, and would appreciate any suggestions.

I've attached a picture (after cleanup) where the buildup occurs. Thanks.

[Roc]

Hi Mick,
The first thing that comes to mind about your issue may well be that water gets around the two flip seats in the aft section of the cocpit.  When I wash my boat, and if I spray the water too much around the seats, I find that it will find it's way in then drip down and collect in that spot you show.  As a test, dry that area off and get a hose and spray in that flip seat area.  You might find water has then collected there.  I keep my bimini up all the time, so when it rains, that area is somewhat protected.  If you keep your bimini collapsed, a heavy rain might affect you, like how a brisk rinsing with a hose is in that area affects me if I'm not too careful.

[Jim Hardesty]

Mick,
In addition to Roc's suggestion.  Shamrock leaked at the emergency tiller port.  The o-ring was bad and the port needed resealed.  It didn't pool where you showed, but your boat may have a different flow path.
Jim

[cmainprize]

Hi Mick I concur with Roc.  The only time I get water in the boat is when it rains and the side panels from our enclosure are off.  I also notice the stuff in the aft cockpit lockers will be wet after I wash the boat.  The lip is not very high and factory foam does little or nothing to seal out the water.  It's even worse if you have a crap built up around the lip, the water backs up quick and runs into the locker. 

[Stu Jackson]

The Mark Is didn't come with any weatherstripping for the lazarette or locker.  An old Mainsheet article from years ago, probably by our guru Ron Hill, suggested doing so.  I used 3/8" rubber stick-on from Ace Hardware.  After 10 years it needed to be replaced, but it worked.

[Wayne]

I had a leak at one of the legs of the steering binnacle and water ended up right where yours puddles.  But of course water does easily get underneath the locker lids, too.

[Stephen Butler]

We had exactly the same problem aboard our 1990 Mk 1.5 - same leak and same puddle location.  Fixed it with Ace Hardware seal strips per the recommendations on this site. 

[Mick Laver]

Thanks all for the suggestions. When I looked at the caulking around the emergency tiller plate (see pic)  I was convinced that was the source of the leak. However, after removing the access plate I saw everything was bone dry (pic) and the O-ring is in good shape. There's no path from the cracked caulking around the plate to the lazaret.

I pulled everything out of the stbd lazaret, gave the hatch another "shower", and discovered the recess aft of the rudder post was indeed collecting water. Not a lot, but enough to explain the source of the leakage. I found some weatherstripping that didn't look too fragile at Home Despot (Frost King EPDM Rubber Weatherseal 9/16") and put it around the aft and outboard sides of the lockers (pic). Problem solved. Thanks again.

[Breakin Away]

Thanks for the tips. It will help with my identical leak problem.

Unrelated question: Is there a special tool for removing the emergency tiller access port? (Maybe it's on the tiller, but I'm not at the boat.)

Thanks!

[Mick Laver]

Yes there's a special tool. Check in your emergency tiller bag.

[Mick Laver]

I thought that putting weatherstripping around the lazaret hatches had solved this problem, probably because I tested it by hosing off the top of the cover and not noticing any more water collecting by my raw water intake. Since the weatherstripping wasn't the problem to begin with, of course adding more solved the "problem." Doh. After a couple of wetter than usual winters here I decided to get serious. I took everything out of the lazaret and the storage area under the aft berth, taped paper towels all over the place, and waited for the rain to come so I could at least see the approximate area where the leak was originating.

It turns out the caulking that seals the liner for the propane canister had shrunk or rotted. It poured a little water where the red arrow in my picture is pointing and sure enough, it leaked right through into the laz. Re-caulking the liner solved the problem.

[Breakin Away]

Thanks for posting this. I tried your weatherstripping fix, and it didn't stop the problem. My caulking is clearly deteriorated, and is a likely source of the problem.

How did you re-caulk? Did you remove the whole liner and re-bed it? (Might be difficult if there are propane vent hoses attached.) Or did you just pick out as much old caulk as you could and shoot some new stuff in from above?

That whole are is a little tough to get to right now under my boat cover, but this will go to the top of my list for as soon as my boat is uncovered.

[Mick Laver]

I'm afraid I wimped out and scraped a layer of the old stuff as I could with a pocket knife, cleaned with bleach and microfiber sponges, and re-caulked over the old. I did look at removing the liner but it seemed to be too much of a PITA for what I was trying to accomplish. We've had a couple of rain "events" (hard to call them storms) come through since I did the job and everything's still dry. I'm confident that was the problem.

[Breakin Away]

Unfortunately, I live in a place with seasons  , so with the winter cover in place I was limited to putting masking tape around the hatch. It rained yesterday, and there was still water that leaked in. So either the masking tape failed to make a good seal, or the leak is coming from somewhere else. I'll try again in the spring.

What kind of caulk did you use?

[Mick Laver]

I taped a plastic bag over the whole propane canister locker. Silly looking, but it worked well enough to tell me that's where the leak was coming from (that and the paper towels in the laz.) I used white silicon seal to caulk it.