Hairline Crack in deck


New Member
I have a 1970 Sunfish I am restoring. I have run into yet another problem and would appreciate some feedback on how to fix it.

I was cleaning the boat this evening and noticed a soft spot at the front, center point of the splash guard. I took the splash guard off to get a better look at it and saw there is a crack running abeam. The crack is about 4”-6” long. It is very close to some of the threaded inserts for the splash guard screws. When I apply some pressure to the area I can see the deck lower at the crack. The crack is very thin right now. I would rather not go cutting a hole in the deck if I don’t have to.

I’m considering placing an inspection port near the crack. I would then turn the boat upside down and try to apply the resin and matting to the inside surface. I have a feeling this would be very hard though, and that I would probably end up getting resin everywhere but on the crack.

If anyone has a good idea on how to make this repair please let me know. I do know how to cut a hole in the deck, insert a backing, and glass it in, but I am hoping someone knows a better way.
Thanks for the help.
Brian, Sounds like a good time to put an Inspection Port in behind the splash rail. A port in this location will allow you to reach the mast step and Dagger Board Well aslo. Go to Wind Line Saile ( How-To section and/or Mike Kilpatrick ( and either will show you how to install a port. Both sites show where to place the port, about 3" behind the splash rail. A 6" port would be best in your case, but do not install it untill you do your repair first. Cut your hole and then mask off the deck.The repair is not diffucult, messy yes. Long sleeves and rubber gloves are a must. Make sure you are dry inside, sand the area well with some coarse paper, clean up the dust (wipe down the area with acetone). Get your resin, fiberglass (3-4" wide pieces cut to size), mixing cans and a couple of throw away pie plates. Mix your resin, pour it into the pie plate, prime the surface around the crack with resin, lay your first piece of glass in the resin and get it saturated and place over the crack, repeating until you have at least three layers, with each layer a little larger (1") than the first. You may want to squeegee the fiberglass to remove any bubbles and the insure good contact. All this is done inside the hull, so you will be working blind and by feel. A small mirror will help you inspect your work. Good luck.
John's advise is all great. If you haven't cut a port you really have no idea what's in there or the condition. It may surprise you.
About all I could add is to repeat about making sure you dry the inside first after cutting for the port. Mositure and resin do not exactly get along.
Now that we're in the interent age if you have on of the cheapo computer cameras they work great for "remote viewing" of the inside of the hull when used along with a good strong light.