356 Keel Delamination

Feb 1, 2010
15
Hunter 356 Northpoint Marina, IL
Hello Hunter Owners,

I just pulled our boat out for Winter storage and noticed the back of my keel has started to delaminate. (See attached picture). I am puzzled how this happened? It's a 2002 and we sail it in Lake Michigan. I am the 3rd owner and have personally never grounded. It had to occur this season because I checked the keel before put-in this spring.

20181013_091942.jpg
I checked around the keel and everything looks fine. I also inspected the bilge and there were no signs of delamination. Also checked the keel bolt nuts and they were snug as well.

Has anybody else experienced this and if so how did you end up repairing.
 
Jan 19, 2010
12,362
Hobie 16 & Rhodes 22 Skeeter Charleston
Bummer. I've repaired a similar delam on a Coronado 23 once. You are going to have to grind all of the loose fiberglass off of the keel... then flair out a good ways and then using concentric patches of whetted fiberglass cloth of increasing size, fill in the missing places... then fair. If you have not done fiber glass work before, it might be cheaper to get the yard to do it. They already have all of the tools etc. and by the time you acquire the tools and know how, you would be behind the curve.

If you decide to do it yourself, there are many here who can walk you through the processes. It is not that hard but it has to be done right or you will have to do it again in a few seasons.
 

SG

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Feb 11, 2017
1,670
J/Boat J/160 Annapolis
The hull of the Hunter 356 is supposedly:
CONSTRUCTION
Fiberglass bottom reinforced with Kevlar from the stem to the keel sump, cored from boot stripe to sheerline with Baltek. Deck is Baltek and plywood-cored fiberglass.

It's looks pretty strange to me. Maybe some water got in there and froze over the winters? You didn't end-up with an anchor line or mooring hooked on the back of the keel?

Looks like some mechanical damage, not just delamination --- unless you "opened it up"?
 
Mar 20, 2004
1,729
Hunter 356 and 216 Portland, ME
What you've got there is not OEM! the 356 keel stub extends down maybe 3" from the hull proper and the all lead keel is bolted/5200'd to that. it looks like someone fiberglassed over the raw lead and that add-on is what's delaminating. what you should see is a glass stub with the lead keel (bare lead) below that. It's shouldn't be covered, and the keel to hull joint is exceptionally strong. Maybe the keel hit something very hard and the stub was damaged; the chosen repair might have been to just glass over the whole thing and hide it instead of dropping the keel and repairing the stub.
 
Jun 9, 2008
1,771
- -- -Bayfield
I agree with chuckwayne. That looks like fairing compound or something that was put on to make the seam from the fiberglass hull shoe to metal keel smooth. Not sure why it is failing. Could be that the preparation was poor. Need to know more about what sort of cocktail was applied. But, it also appears to be cosmetic rather than a structural issue.
 
Dec 22, 2012
95
Hunter 27-3 103 Gables By The Sea
From the drawings in the Hunter 356 manual and website, the top of the keel that connects to the hull is "U" shaped. See attached keel drawing from website. That is the front and back touch the hull proper and the center of the keel, where the hemongo keel bolts are, touch and attach to a sump which hangs down and is what you see when you look in the bilge. For instance Beneteau keels are attached directly to the hull and there is no sump. The aft part of the keel that you show in the picture is where the keel contacts the actual hull proper aft of the keel sump. My guess is it is fairing. After mating the keel, it is probably necessary to use some fiberglass material to fair the joint. My thought is you are going to have to carefully grind that to see what you have. Careful not to grind into hull laminate. Once you start grinding it should be apparent what is what. I would grind on that loose stuff first. Why did it come apart is anyone's guess. Not much likes to stick to lead, it's kind of greasy. I had a J30 with fairing and it came apart. The solution was to grind and replace. The yard guys have probably seen some hard grounded boats so they should be able to know if there is any structural damage.
 

Attachments

SG

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Feb 11, 2017
1,670
J/Boat J/160 Annapolis
The Cause? I would try and understand that too before I simply patched it.

The original had Kevlar, not just FRP.
 
Mar 20, 2004
1,729
Hunter 356 and 216 Portland, ME
the top of the keel really isn't "u" shaped - don't know why the drawing looks like that. The sump is a really thick section, about 3-4", that sticks down and the keel is put on with 5200 and those huge keel bolts. the keel doesn't touch the hull lines at all. The joint is faired with polyester fairing compound, no frp at all, and it is pretty brittle and can crack or fall off. the fairing is only a couple of inches wide.
The Kevlar is in the laminate schedule and stops just before the keel (it's under the gelcoat). I would strip all of that stuff off - it's not needed to protect the lead, and as SG said, I would want to know why it's there.
 
Feb 1, 2010
15
Hunter 356 Northpoint Marina, IL
Chuck, do you think Hunter did the fairing or did someone do it after the fact.

Should I consider putting in an insurance claim on this? What would you estimate a yard would charge to fix?
 

SG

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Feb 11, 2017
1,670
J/Boat J/160 Annapolis
I clarify what ChuckWayne meant was the Kevlar is embedded in the glass which is in the main coating below the gel-coat coating (I think the distinction is that you won't be seeing Kevlar fabric if you just strip off the gel-coat).

In answer to your questions, JVorhies, if you hit something that caused that damage, presumably you might have reported it contemporaneously? How would the deterioration of the aft portion of the keels trailing edge been caused by a collision with something going forward? If you backed into at sufficient speed to cause the delamination at the keel stub, then you would have seen some material signs lower on the trailing edge. If the ledge was just below the water line, the rudder wouldn't have survived.
 

Bob R.

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Jun 5, 2004
160
Marlow-Hunter 40 Pasadena, MD
I got confused when I started reading this thread yesterday. I thought it was a continuation of an old thread from last March of almost identical keel fairing damage caused by a hard vertical grounding on a sand bottom while the boat was anchored in shallow water and the boat rose and fell riding the waves or wake. That boat's damage included a visible horizontal crack along the entire length of the keel stub/keel joint, plus the fairing damage at the aft end of the keel. I tried, but couldn't find some old photos I took of the keel of our 2002 H356 after I sanded off bottom paint and ground off a bunch of blisters that had formed in the barrier paint covering the lead. I had exposed most of the stub/keel joint, which I remember as being straight front to back. I do not recall seeing that much fairing material at the aft end of the keel. I do have a couple of photos of Marlow Hunter fairing the stub/keel joint for our new MH 40. The fairing is not more than 3-4 inches wide. The photos were taken in May 2018.

20180503_073035_1525347537701.jpg 20180503_073050_1525347537645.jpg
 
Jun 8, 2004
10,024
-na -NA Anywhere USA
@chuckwayne
Here we go again on the lead keel attachment. Chuck Wayne is correct because I was a stocking dealer of that boat not only worked on them but watched them in every aspect being built. Thank you for advising Chuckwayne. See the other thread on this just below this thread
 
Dec 22, 2012
95
Hunter 27-3 103 Gables By The Sea
Not to argue with you guys but my 2003 356 is built exactly like the drawings. The keel is U shaped and it does contact the hull fore and aft (actually there is a little sump, maybe 1" or 2"20181030_094957.jpg 20181030_095037.jpg ). The main sump is a good 10 inches. The pictures below from my boat are exactly like the manual and keel drawing.
 

SG

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Feb 11, 2017
1,670
J/Boat J/160 Annapolis
Now I'm confused?
JVoorhies took the picture below of the trailing edge of HIS keel where it meets to hull. The delamination is at the stern (not along the horizontal joint running fore and aft, not along the leading edge, not "half-way down", etc.)

I don't see a keel stub like those shown in some subsequent posts?


upload_2018-10-30_11-27-54.png
 
Dec 22, 2012
95
Hunter 27-3 103 Gables By The Sea
That's because the keel is U shaped (fore and aft) and the aft end is bolted to the hull with maybe a little sump which would be above the delamination. The other question is why is the delaminated part flared/pulled out like that? Did the owner do that for emphasis? If it just came loose, usually it would just detach but stay in contact. Could it be the results of freezing trapped water. In Florida those problems don't happen. Seems if it would have grounded hard enough to force the fairing out then there would be some real structural damage. Looking very carefully at the photo there seems to be an oval area around the trailing keel edge, particularly to port, that does not match the texture of the area outboard to p and s. Why don't you call the yards where the boat was previously kept. If there were repairs, someone would remember. Insurance claim?
 
Dec 22, 2012
95
Hunter 27-3 103 Gables By The Sea
By the way, reputable yacht brokers work on a full disclosure basis. Structural damage due to a grounding would certainly qualify. That is a question that is commonly asked at listing time. Most likely it is just loose fairing but if it turns out to be previous serious damage you may have some recourse through the courts.
 
Mar 20, 2004
1,729
Hunter 356 and 216 Portland, ME
CharlieSea,
I suppose the 2003s could be different from the 2002s, but I don't know why they would make such a major change after building several hundred 2002s....... None of the 356s I've seen look like that..
My sump looks just like yours, but maybe that drawing represents the interior of the keel - I've definitely got a straight line where the drawing shows the "u" and the stub goes fully fore and aft the length of the keel I had to redo the fairing so I had that area opened up
 
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Feb 1, 2010
15
Hunter 356 Northpoint Marina, IL
The flair/pull out was exactly the way it was when I discovered her delamination.

I canceled out freezing because I put in this spring and there was no damage at the time.

I have never run a ground.

I originally thought maybe they put to much weight on the keel when they placed her on the cradle, but there was no damage on other areas of the keel. This is the 1st year I didn't watch them pull her out so I cannot speak to any issues they had pulling her out.