Skeg Weeping

[capjules]

Skeg Weeping

Hello,

I have Fantasia 35 Hull 69, year 1980

My skeg is weeping where it joins the hull just behind the prop.

the liquid coming out smells like resin and one drop hanging off looks clear
but as it builds up in the bucket it is almost black.

one drop about every thirty seconds for two days, have not been
back to the yard so don't know if it stopped yet.

anyone ever have a similar situation and if so how did you resolve it ?

I have attached two photos.

Thanks

Jules

 

[Hermit Scott]

When I hauled my boat, I had a few places that did that. I was very concerned. My favorite tool is a 4-1/2" grinder with either an 80 grit flap disc sander, or a wire wheel to remove fiberglass in short order. I used the wire wheel and started cutting away right where it looked like there was a leak through a crack.
Soon the area I was cutting into turned into a perfectly round hole with a core in it, water was leaking around the core.
A PO had drilled holes in the bottom of the bilge at angles so the bilge would drain while the boat sat on the hard. When they plugged them they did a very poor job. I beveled them out inside and out and layed in fiberglass and epoxy.

 

[sailingdog]

Is the hull or skeg cored? The discharge could be caused by rotted core material.

 

[capjules]

the hull is solid 3/4" below the water line and the skeg is solid as well, 3/8" glass skins filled with fiberglass mish mash.

the skeg is externally mounted into a hull cavity under the aft bunk and then bolted
in and heavily glassed over, there is no sign of damage on the inside, no water intrustion, delamination etc...

it is glassed all around the hull on the outside.

on the outside where the water drips from sounds delaminated
and the spot where it is dripping is right about where the skeg meets
the hull in the cavity is goes up into.

thanks for your replies

 

[capjules]

I have added a design drawing of the skeg installation to my original post.

thanks.

 

[BobM]

Sounds like your mush is living up to its name. Have fun with the grinder. It is probably the only way to find out what the heck is going on and to get back to good material.

 

[Newbie]

just thinking out loud here. Could you have backed into something and damaged the skeg?

 

[kloudie1]

Guessing here, but a scenario would be that the crcak forward started from fatigue or a minor contact with something in the water or on the hard.. Water has gotten in and now the stainless bolts are rotted from crevice corrosion.. The lower integrity of teh joint is letting it move more ... Water is showing black from stainless corrosion residue and smell is from trace of unreacted resin that is just now seeing water as the crack progresses between the skeg molding and the hull.. Solution is the same, start digging and stop when you get to good glass and fairing compound.. New bolt/bolts, some epoxy lay up after all dry.. fair with an epoxy fairing compound.. Good luck !

 

[capjules]

Hi Claude,

I did have the bottom bumped twice as sat along a very shollow seawall last year. if a power boat went by a little to fast the wake would lift the boat a few inches and then it would bump bottom. After it happened twice I moved it. On the inside of the boat there is no sign of damage, water intrusion or delamination.

So that sounds like pretty good assesment but I also have a few small blisters on the hull that ooze the same dark fluid with the same smell so I'm hoping the coloration is not from corrosion on the bolts. The bolts are 3 of 3/4" and all the stainless on this boat is of very high quality so I have to assume these bolts are of good quality as well and not compromised nearly enough to replace at this time if the water did get in contact with them for a few months.

I snorkel under the boat most everytime i take it out so i can keep an eye out for stress cracks or movement. It has no stress cracks or movement right now. It is rock solid and I sounded the whole thing and there is no delamination except for right
at this crack.

Somone is going to grind it in the morning so see how far the water has gotten in.

Thanks,

Jules

 

[capjules]

Fiberglass mush is not bad

Sounds like your mush is living up to its name. Have fun with the grinder. It is probably the only way to find out what the heck is going on and to get back to good material.

fiberglass mush is resin mixed with chopped glass mat.

It is solid and I prefer it over foam cores in skegs and rudders.

if the skin on my skeg or rudder gets holed what is behind it is solid
fiberglass and the water has no place to go.

If the skin of foam cored rudder gets holed the whole thing fills with water.

and I know many people are out there are sailing with water in their foam cored
rudders and it's rusting out the stock.

of course solid skegs and rudders are not feasable for lighter boats.

my problem is between the skeg and the hull not in the skeg.

 

[capjules]

P.S. Claude,

the water would have to be inside the skeg to get to the bolts
and the skeg is solid glass. wouldn't it take many years for the water
to blister it's way that far up through a foot solid glass. plus I think the whole skeg would be blistered out, delaminated and working by now if water had gotten all the way
the bolts.

It looks and sounds very healthy over all and I think it would show a good deal of symptoms if the water was that far in.

 

[kloudie1]

uhhhhh Not to be flippant, Jules, but 21 years is pretty many years.. I was thinking that the bolts were part of the support system of the skeg.. That crack at the leading end of the skeg works like a capillary and the water spreads at the tip of the crack along the interface of the hull and skeg molding. This water is more or less stagnant and will attack even the best grade stainless fasteners. Attached photo is of a 15 year old skeg tip bolt from a Tartan 37 .. The stainless was analyzed with a nuclear device ( we had those at work) and it is in fact high grade 316 stainless.
Once the skeg molding has un-stuck from the hull itself, water will enter the crack and work its way to the end of the un-stuck parts.. Not saying by any means that the problem is only that!! but the scenerio plays through when I see the crack and the way it is following the interface.. and hear the amount of water that is leaking out.. One approach is to perfectly seal the crack, glass it over, and go on the assumption that no more damage will happen because no more water is entering.. and it has been strong enough up to now, it may be OK..?? But since you are out of the water and have access, it is prudent to get the crack out to the end and, using epoxy, work your way back out so that the traces of digging are well bonded and invisible.. Good luck with it .. I hope I am wrong !!

 

[capjules]

it started last year

I don't know why you say 21 years.

at survey two years ago it was not like this.

at haul out last year it was not like this.

I bumped the bottom last year after haul out.

so this water has been in for less than one year.

unless I am missing something.

and what I instructed the yard to do is get to the crack end to end
and about eight inches forward and aft of the crack, we are going
to remove a good amount of matieral, dry it out and reglass.

 

[BobM]

Presuming...

fiberglass mush is resin mixed with chopped glass mat.

It is solid and I prefer it over foam cores in skegs and rudders.

if the skin on my skeg or rudder gets holed what is behind it is solid
fiberglass and the water has no place to go.

If the skin of foam cored rudder gets holed the whole thing fills with water.

and I know many people are out there are sailing with water in their foam cored
rudders and it's rusting out the stock.

of course solid skegs and rudders are not feasable for lighter boats.

my problem is between the skeg and the hull not in the skeg.

I agree about cored rudders...but you are presuming that the mush actually hardened. Keep us posted. No alternative but the grinder in my opinion, so you are on the right path.

 

[kloudie1]

Not throwing stones here, Jules.. I hope you are right, as I said..I think the path you are taking is prudent .. open up until ya don't find wet or crack and make sure ya get it sealed and bonded on the way out.. If the crack and wet goes to the bolts, look at 'em.. If it is dry before ya get to 'em, then ya probably have no problem with the bolts.. It can be very difficult to find places where water may enter an underwater interface ... it is easy to find where it comes out.. but that is not always where it went in.