Boat bottem leaks

[corbinstein]

Does anyone know the thickness of the bottom of a '75 SJ21?
I've got a small leak and will need to add some fiberglass, but wonder how thick it is.....

[cguthrie]

Depending on where, the hull can be anywhere from 1/8 inch to 3/4 inch thick

[Diarmuid]

Where is the leak? Unless you have a puncture wound, the SJ21's only common point of hull leaks is the glassed-over wooden strips to either side of the keel box. These can seep in a remarkable volume of water; adding more FG won't fix it. The leak comes from the keel gasket screws.

[Eddie10]

If you have an auto bailer, make sure you bubble tested that area - especially if it hasn't been removed in a few years, the screw hole can let in a lot of water. If you are getting water over the deck, check mast step as advised above and inspection ports. You don't mention what year the boat is, but lastly make sure you test the drain plug in the transom - the North American boats with the screw in plugs have a rubber o-ring, when it's missing the plug leaks even when screwed in tight.

[corbinstein]

No auto bailer, and I can't find a Plug at the back.... Does anyone know exactly where the plug should be?
Pics please....

[bluepearl]

Most of the boats I've seen don't have a drain plug in the transom. If you are getting enough water in your boat to need a drain, you have serious problems.

[Diarmuid]

It can be amazingly tough to figure out where water is coming from. Here's the classic test: Dry everything from the mast step to the back of the keel box as thoroughly as possible with sponges and a terrycloth towel. Really squeaky dry. Might even want to do a wipe down with an alcohol-soaked rag, then let it flash off.

Then shake a thin layer of baby powder, corn starch, or (if you are really brave) an envelope of Kool-Aid powder on all surfaces, plonk the boat in the water, and come back to check it every couple hours. You'll see a growing wet spot where your leak is coming from. Our boat started collecting water during daysails; the baby powder revealed the keel gasket screws were to blame. Fixed those. Still getting a little water in the bilge on rowdy days; powder test proved it was splashing in thru the keel pin hole. That's okay. Finally, last year, we were finding water in the bilge while the boat was on its mooring. Not much, and not all the time. Couldn't prove any obvious source near the keel box. So I got ambitious and sprinkled powder more widely. Aha! Mush on the quarterberth. Bloody port aft window was leaking rain. That's why it was intermittent. The water was rolling off the seat into the bilge; then the bench would dry off, leaving no evidence.

Now our boat smells like a nursery, but that's the price of detectoring.

[corbinstein]

I'll try the baby powder check next time she's in the water.....

I've got another leak up front coming from under the berth and the (not sure what you call it), but the hole under the berth is full of water as well as the "tank" around and behind it is full too....

I'm sure I've got punctures because there are old repairs that I suspect leaking....

How can I get this think up high enough to glass in areas?

I'm thinking about borrowing a trailer from someone who has a fixed keel so that I can inspect the bottom of my boat if possible...

[cklamp]

Corbin, check your windows, and the areas where the pulpit mounts if you have one, as well as the holes for your Mast step, and any other cleats that might be in those areas. I had very similar water leakage as you and it was coming from those areas.

As far as lifting goes, many marinas have a hoist if you can get that trailer... also check out Fleet 1's web page, there are a couple of people in Fleet 1 that have built our own lifts using a similar design to what Stephen Jenson has used. It's on our tips and tricks page. There are dimensions for a lifting beam too, so it should give you a good start on some ideas.

I built one for about 40$ in lumber, and 50$ worth of chain hoist at harbor freight when it was on special.

there are many ways to lift an Sj21, I think some other's were listed on hubbards site too.

Later
C

[kuriti]

I put some thought and research into lifting the boat inside my garage next winter for painting and bottom inspection. Since i can't leave it in the driveway or back yard (home owners gestapo) I need a way to lift it about 5 feet off the ground with nothing overhead. this link had some ideas. The guy at the bottom of the page who lifted an Oday 23 seems to be the best method i could find. Not sure if i will try it or not. probably get a quote for having someone else do it first...

http://forums.sbo.sailboatowners.com/sh ... p?t=104228

hope this helps.