Cracks Appearing in Hull

Dunwishin

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I have a 2004 330 xpress, last year Mar. 09 a minor crack appeared on the port hull just above the water line at the galley sink skupper (I believe the location of the crack is just aft of a stringer). Over this winter the crack trippled in size, extended below the water line and additional cracking appeared forward of the stringer. Spoke to a Grady rep @ the NY boat show and they advised they will refer the matter to the local dealer for resolution.
If anyone else has had this problem, any causes and how the the matter was resolved would be appreciated.
 
Cracks

Hi Dave,
I have a 97 Marlin that developed a crack last year in the bow. The crack ran from the tow eye right down the center V about 4". It wasnt structural just gelcoat. I had a local fiberglass repair and i thought he did a great job because i could not see the crack after the repair. This winter after the first freeze the crack reappeared. I also spoke to the GW rep at the NY Boat show and he said the repair needs to be made with epoxy. I will have the repair done again by same guy and tell him to use epoxy this time and i will see what happens. I have never seen a crack at the waterline or along the side of the boat. I am on my 3rd GW and this is the first I have had this problem.

Good luck with the repair.
 
Dunwishin, can you post a picture of this problem? Lanie J, do you recall if the initial repair actually went into the glass area? It's interesting that GW told you to use epoxy to fix a gelcoat only crack. The repair guy will either have to match the gelcoat color with paint (above the waterline area) or really know how to bond gelcoat to cured epoxy.....no big deal if its below and bottom painted.
 
On the 330, the side hull is cored - plenty of strength, did you hit something (like drift fast sideways into something down low) or get the thru hull clipped on the side of a concrete bulkhead or hard dock?

Grady has a network of fiberglass repair shops around, will refer you to one to evaluate. The crack has to be stopped and reinforced to prevent reoccurence. There may be voids in the orignal glass, easy enough to grind out and build back up. I wonder how the inner skin looks.
Should be accessible from the cabin.
 
Was this ever resolved? I have a similar sounding crack appearing on my 1999 marlin
 
Water in core, freezes then expands, cracks gel coat. Possibly... But who knows untill it gets ground away what your issue is. If so more grinding needs to happen then dryout. Gel coat is not compatible with epoxy. Gel is polyester which is the resin used to build boats. Epoxy is much tougher, can take flex and is usually used to fix boats structurally inside where it doesnt' need to be gel coated. Epoxy costs alot more. There is something called a tie coat that maybe allow gel to stick to epoxy but I'd talk directly to a fiberglass shop. A "rep" won't know any thing.

Maybe a simple fix of grinding back putting a few layers of glass on then gelcoating again to make a structural repair. The crack is there for a reason.
 
Water in core, freezes then expands, cracks gel coat. Possibly... But who knows untill it gets ground away what your issue is. If so more grinding needs to happen then dryout. Gel coat is not compatible with epoxy. Gel is polyester which is the resin used to build boats. Epoxy is much tougher, can take flex and is usually used to fix boats structurally inside where it doesnt' need to be gel coated. Epoxy costs alot more. There is something called a tie coat that maybe allow gel to stick to epoxy but I'd talk directly to a fiberglass shop. A "rep" won't know any thing.

Maybe a simple fix of grinding back putting a few layers of glass on then gelcoating again to make a structural repair. The crack is there for a reason.

One on each side about the same spot
 

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The one guy that looked says its cosmetic. I'm going to get a second opinion soon. it concerns me at the moment started on one side had the gel coat repaired and it came back along with the other side
 
The one guy that looked says its cosmetic. I'm going to get a second opinion soon. it concerns me at the moment started on one side had the gel coat repaired and it came back along with the other side

What you're seeing is cosmetic but the question is what caused the crack. Impacts spider web gel coat. You'll at least need to remove the bottom paint and gel coat to get down to the first layer of glass to see if the glass is cracked. Basically you'll have to grind until there is no more crack.

Or just fill it and walk away.

Fiberglass is almost infinitly fixable so it can be repaired for sure but the direction and location of crack is strange. Stress cracks on corners and curves that's very normal but this is different. Hope it's not majore when you grind it.
 
Was anything every figured out on this? I am having the same issue on a 2000 Grady marlin
 

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Was anything every figured out on this? I am having the same issue on a 2000 Grady marlin
Has the boat been repowered?

The picture to me is not gel coat cracks. It looks like something serious and structural. It is possible that it could be freeze related. Is the hull stored in an area that has freezing weather?

Can you also post a picture of the boat on the trailer? I would like to eliminate an improperly sized trailer as a factor.
 
Could it have been a gel coat crack that had moisture in it , which the froze and opened up? Also was the boat trailered for a long distance?
 
Was anything every figured out on this? I am having the same issue on a 2000 Grady marlin
Zooming in on the picture, those cracks look a whole lot deeper than gelcoat stress cracks (which are primarily cosmetic). This appears (from the picture, anyways) to be more structural. But again, I only have one picture to base this on. I would, however, recommend having a qualified surveyor or a knowledgeable shop take a look at it and, at the very least, inspect the hull for major damage or a separated bulkhead.

Your crack does NOT appear to be the same as what's talked about in this thread.
 
When Coosa, or anything else, is used to core the hull side, are pieces end-butted, over-lapped, scarfed, or other, before being glassed over?
Not that I've ever seen. The coring, itself, isn't structural and doesn't need scarfing (or similar). A simple end butt is all that's needed - and even that doesn't have to be perfect. It's the separation of the two layers of glass that is key. The core's main purpose is simply to keep the two layers separated - THAT'S what adds strength. When a core is compromised, though, the core and glass layer loose adhesion and that gives us that "soft" feeling and flexing.