Hey guys,

   I have only worked on aluminum hulls so I have complete ignorance on fiberglass.

  My buddies boat has a nasty gouge out of his hull righ on the keel. I thin kit was from sometime his boat went on the trailer a bit and hit a chunk of metal. Now it did not punch a hole right through, but it actually dented the fiberglass. This was about 3 months ago i think he told me.

  Last time we went out, I noticed before we even got in the water, there was water that appeared to be dripping/seeping out of that dent. My thought was he waited to long to fix it, and now there may be water and damage to go along with it in there.

 Just how much damage can you do to the hull/gel coat of a fiberglass hull before it should be taken out of the water and fixed immediately? With Aluminum, obviously you can scratch it pretty good and not have to care too much. My rough impression from what I have read on here is this is not the case with a fiberglass hull.

i would get it fixed.  Our boat had a spot that was made the boat leak and it didnt really look that bad.  When the guy went in to fix it, he had to go back an extra 3 feet to fix it.  

Fiberglass composite is made of two materials, the fabrics, mat and roving, and the resin which is a plastic.

The resin gives the product its shape, and the fabrics provide structural strength.

You mention a "dent".  What has happened is not a dent such as you get in metal.  A sharp impact crushes the resin/plastic into a powder, which water can permeate.

The gel coat is the outer layer of the fiberglass which provides color, and protection for the hull.  Polyester resin which is the most common type used in boat building can absorb water.  The gel coat is impermeable to water, and thus protects the hull.  No matter if it is white, a color, or a metalflake, the main purpose of a gel coat is to seal the hull from the water.  

When water gets into the fiberglass either through impact damage such as you describe, or scratches through the gel coat, it can wreak havoc in the colder climes.  The moisture can freeze, expand and damage the composite in a way that allows for even more water to penetrate the structure, freeze and do even further damage.

While the damage you describe will not result in catastrophic damage such as hull failure, it can result in the gradual degrading of that area of the hull.

It's important to get it fixed properly.  That includes finishing the patch by applying gel coat.  

Houston, you've got problems.  Once the outer shell has been compromised down to the fiberglass matting, especially in an area below the water line, the fiberglass will begin to absorb water and then delaminate.  Once that process is underway the repair can be expensive as the hull area that is damaged must be removed and then gel and new matting extending beyond the actual damaged glass.  Possible repair from the inside may be necessary which would involve pulling the cap.

$$$$$ the longer you wait.  

Houston, you've got problems. Once the outer shell has been compromised down to the fiberglass matting, especially in an area below the water line, the fiberglass will begin to absorb water and then delaminate. Once that process is underway the repair can be expensive as the hull area that is damaged must be removed and then gel and new matting extending beyond the actual damaged glass. Possible repair from the inside may be necessary which would involve pulling the cap.

$$$$$ the longer you wait.

Exactly!

Awesome info guys! Thanks!