Leak in 23.5 water ballast tank

Sep 19, 2016
172
Caliber 33 Sebastian, FL
After eliminating all through hull fittings as the culprit in my persistent water leak, I tried adding some blue food die to the ballast tank. Subsequently finding blue tinted water in my bilge confirms a leak in the ballast tank. I can't find any imperfections in any visible part of the tank so I guess the next step is a borescope to try and find the exact location of the leak. Any thoughts on how to proceed? From my searching, I gather that there are not many options for actually fixing the tank if it ends up being under the cabin sole.
 
Jan 19, 2010
12,362
Hobie 16 & Rhodes 22 Skeeter Charleston
Sorry to hear of your problems. That is a real bummer. You could try putting it on a trailer... and with the tank empty and the under-hull valve closed..try reversing the hose on your shop-vac and place that over the vent plug for your tank. Then start pouring soapy water around in your boat and look for a stream of bubbles.
 
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Jan 19, 2010
12,362
Hobie 16 & Rhodes 22 Skeeter Charleston
I actually did this sort of test recently with a hobie 16 I have. I kept getting water in the starboard hull. I put my shop vac on reverse over the drain plug and sloshed a bucket of soapy water over the boat. Found the leak in seconds.
 
Sep 19, 2016
172
Caliber 33 Sebastian, FL
Sounds simple enough. I will give that a shot tonight. Thanks.

Of course, the real trick will be fixing it after I find it. Seems like I'd have to cut away the cabin sole to get to the tank. Not sure how feasible that is considering the one piece construction. The boat was a basket case when we got it so I've already paid for all new sails and running rigging. I'd hate to see all that go to waste but this being a boat brings a whole new dimension to the sunk cost fallacy.
 
Jun 2, 2004
3,390
Hunter 23.5 Fort Walton Yacht Club, Florida
You could narrow it down by tilting the boat forward or back and then filling the tank half full ten seeing if you have blue stuff in the bilge. There is actually a lot of visual access to the tank. I found that sticking my cell phone into hard to see places and taking a picture was very helpful.

Good Luck
 
Jan 19, 2010
12,362
Hobie 16 & Rhodes 22 Skeeter Charleston
@PropellerHead

Have you reached out to Crazy Dave? He helped design these water ballast boats and knows a lot about them. Your situation makes my stomach hurt. If worst case scenario happens, I bet you could keep the sails, part-out much of the other pieces of your boat and have about half of what you need to buy another H23.5. Also sell the old sails and O.B. on your new H23.5 and recover some more. Once your old boat is parted out, sell the trailer. You can probably get 3/4 there (less the PITA of it all). Lets hope it does not come to that but if it does
Trailer = $1,000
O.B. = $500
Winches = $200
Swim Ladder = $200
Other railing = $500
Old Sails = $300 - $800
Mast and Rigging = ???? ($1000 total?)
Ports and windows = $1000 (combined)
Roller furler = $500

If you do have to cut the sole out and decide to repair it.. it could be an opportunity to do something really cool. Rustoleum and other companies make garage floor epoxy coatings that are BEAUTIFUL (do an image search of garage floor epoxy). Personally I think this would look great as the sole of a sailboat... and the epoxy might actually seal a crack or two if that is where the leak is found AND you can add anti-skit to the mix for a very functional cabin sole.
 
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Jan 19, 2010
12,362
Hobie 16 & Rhodes 22 Skeeter Charleston
You could even tape off some very cool designs in your sole and use more than one color. Lemons out of lemonade ????

You could start a reality TV show (everyone else seems to be) called "Pimp my Boat"... go nuts!:yikes:
 
Jan 19, 2010
12,362
Hobie 16 & Rhodes 22 Skeeter Charleston
Sorry, I'm getting carried away... but here is another very cool epoxy mix
 

Doug J

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May 2, 2005
1,192
Hunter 26 Oceanside, CA
You say the boat was a basket case when you got it. Are there any mods the PO did that involved screws, drilling, cutting, etc, anywhere near the ballast tank? If so, that would be suspect.
Also, can you describe how you did your blue tinted water test? Are you sure it wasn't leaking from the vent or valve holes?
 
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Jun 4, 2004
392
Hunter 31 and 25 and fomerly 23.5 Stockton State Park Marina; MO
Two common areas for a hard to find leak on the 23.5 are:
1) The bilge pump line has been re-located so it does not remain above the water line. This allows water to back flow through the bilge pump when heeled over on starboard tack. This line should come into the galley area and loop up as high as possible and then come down to the through hull exit.
2) The area under the mast step contains the single bolt that holds the centerboard bracket. This bolt comes through 2 layers of fiberglass structure; the hull lay-up and the ballast tank top lay-up. It's possible (probable) that when the centerboard has been dropped and reinstalled that enough sealant was used to keep outside water from coming in but not enough to stop ballast tank water from leaking out. This joint is above the water line so only will leak when under way. Put some tissue around the edge of the aluminum plate that the bolt goes through and go for a brisk sail or motor. If this soaks you have found your leak.
Both the above are solutions only if your water is coming in only under way. If rain or wash water appear to be the source then all fittings through the deck and cockpit must be checked. Additionally, I found a leak on mine in an unlikely place. The navigation lights on the bow were allowing water to run down the wires into the bow pulpit and into the for-peak. Creating a drip loop in the wire before it enters the pulpit and caulking the wires and grommet at the pulpit entry cured this.
Good luck!
Dennis
 
Jan 19, 2010
12,362
Hobie 16 & Rhodes 22 Skeeter Charleston
The op said he put dye in his tank and found the dye in the bilge. So it is not rain water or a siphon effect from the bilge drain.
 
Sep 30, 2016
339
Island Packet IP 44 Ventura, CA
I hope you get your boat fixed, and without too much pain. But if it all goes south Ive read threads on this forum recently where folks are looking for a 23.5 trailer and mast. Im sure you could sell the sails and part out the rest of the hardware. A hassle, but it would recover quite a bit of cash.
 
Sep 19, 2016
172
Caliber 33 Sebastian, FL
Didn't get a chance to do the soapy water test last night but I might be able to do it tonight.

I did the dye test with the boat at anchor over night in calm water. The area over the center board bolt is always dry as is the through hole for the depth transducer and the area around the ballast tank vent.

I read somewhere that someone found that the tank had been punctured by the screws that hold the down the bracket for the port-a-potty. That's a spot that I intend to focus on. No other mods on this boat.

Good to know that I'll be able to get some of my investment back if I do give up on the boat. I'm not there yet though. In fact, I've decided that the leak is slow enough to live with. It takes about ten hours to fill the bilge enough to trigger the bilge pump. On the morning after spending a night on the water, I'll have my wife stand on the port side while I run the bilge on manual to get all the water out and then she's good for the day.
 
Jan 19, 2010
12,362
Hobie 16 & Rhodes 22 Skeeter Charleston
I read somewhere that someone found that the tank had been punctured by the screws that hold the down the bracket for the port-a-potty. That's a spot that I intend to focus on. No other mods on this boat.
Lets hope that is what it is for you. :pray:
That would be an easy fix.
 
Jun 2, 2004
3,390
Hunter 23.5 Fort Walton Yacht Club, Florida
Another thought was to use clay to create dams to isolate which end or which side the leak is occurring.

Glad you found the post about the screws on the porti pottie I thought of that but forgot to mention it.
 
Jun 8, 2004
10,024
-na -NA Anywhere USA
You all beat me to punch on the screws holding the pots poti down which is why Hunter used short screws. I have seen longer screws used by dealers installing that or by an owner.

Other areas to look.
1. Air vent plug not tight or worn out
2. Wing nut gasket worn out
3. Look at base of compression post where it rests into a larger base and note any small screw hoes in the compression post just above to see if any water coming thru. If bolts missing it takes a #10 bolt
Keep us posted
 
Sep 19, 2016
172
Caliber 33 Sebastian, FL
So far, the soap bubble test has been inconclusive. I went ahead and ordered a cheap endoscope off Amazon. Will keep you guys posted.
 

DJN51

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Oct 26, 2009
377
Hunter 23.5 East Chicago In
Have no idea if it would work,but if boat is rough how about dumping couple bottle of radiator stop leak in ballast.and sail her to get it to move around and reverse shopvac to pressurise the ballast tank to force stopleak particles to leak.or even sawdust.
 
Jan 19, 2010
12,362
Hobie 16 & Rhodes 22 Skeeter Charleston
Have no idea if it would work,but if boat is rough how about dumping couple bottle of radiator stop leak in ballast.and sail her to get it to move around and reverse shopvac to pressurise the ballast tank to force stopleak particles to leak.or even sawdust.
I like it...That sure is creative thinking... but I think stopleak requires heat to activate. Also, I would not want to be the first person to try this.