H260 Remove and Replace Centerboard While in Water
I changed my centerboard uphaul line by dropping the centerboard while the boat was in the water and then reinstalling it with the new CB uphaul line attached. It was actually a fairly easy process if you have an area to work in that has a shallow gently sloping bottom with relatively good visibility. Mine was done in a Florida lake with a sandy bottom.
Materials:
12" long 3/4" diameter threaded rod (home depot). Weld a strong steel eye carefully on to one end so that you can still slide a 3/4" nut past the eye on to the threaded rod. (see Photo)
Cradle for the centerboard (see photo) Mine was constructed with 2 by 4's and 2 by 12's.
15' to 20' of line. We'll call it CB removal line (attaches to the eye on the threaded rod). I used a spare piece of Sta-set double braid.
This narrative only addresses removing and reinstalling the CB. If replacing the uphaul line follow the widely discussed process on the forums.....tracer line, etc.
To Remove
Need to be in roughly 4' to 4.5' of water at the CB for it to drop to the bottom and clear the hull. Less if you pump out the ballast tank. Wooden cradle isn't needed for this step.
The dinette table was lifted out of the way by cutting a short piece of 2" schedule 40 PVC in half lengthwise and clamping it to the compression post with hose clamps. (see photo)
Run a ratchet strap or straps around the boat at the aft end of the CB trunk to hold the CB firmly in place. I also stretched a tarp under the boat to catch the CB bracket pins if they fell out during the CB removal (they did).
Remove the CB trunk cover plate to reveal the factory bolt in the CB bracket. Cut away sealant, remove factory bolt, and install the threaded rod about 3/4" into the CB bracket. If the ratchet strap is tight then everything should be in alignment. Your clue will be as you loosen the factory bolt. If it spins freely after a few turns, then alignment shouldn't be an issue. If it is tight or binding, you can visually determine if the bolt is centered in the trunk and shift the CB bracket slightly to free any binding. If misalignment can't be achieved at this point, don't attempt to force the threaded rod and risk cross-threading the CB bracket. Just release the ratchet strap and hopefully the CB will fall to the lake bottom on the tarp.
Assuming you have the threaded rod in place, attach the CB removal line to the eye with a simple bowline knot. I did this alone, so I ran a 3/4" nut finger tight on the threaded rod to hold the CB bracket in position, then loosened the ratchet strap and let the CB swing down to rest on the bottom. While holding the line, spin the 3/4" nut off the threaded rod and gently lower the remaining centerboard, CB bracket and threaded rod to the lake bottom on the tarp. Mine took a little wiggling but dropped right out. At this stage you don't really feel the true weight of the CB due to the buoyancy of the water.
Float the boat out of the way and you can simply walk right up to the whole assembly lying there on the lake bottom. Unscrew the threaded rod with the CB removal line still tied off inside the boat for later use. Lifting it out of the water at this stage is when you feel the full weight. I had some fiberglass repairs to do so it had to come out.
To Re-Install
Note - During reassembly I used the zip tie trick to keep the centerboard pins in place (thanks to others on this forum). New uphaul line was in place, ready to be pulled thru with tracer line.
Put the cradle in place and drop the CB in position (see photos). CB bracket should be in roughly 4.5' to 5' of water depth.....yours may vary.
Screw the threaded rod back into the CB bracket. Remember that the CB removal line runs from the eye on the threaded rod back up thru the CB trunk thru the factory bolt hole and is tied off inside the boat.
You really need a second person for this step. Float the boat over the CB sitting in the cradle while trying to align everything as much as possible. Pull the slack out of the CB removal line and the tracer for the new uphaul line. As you pull on the CB removal line it will naturally pull the threaded rod and CB bracket toward the trunk in the bottom of the boat and virtually guides the threaded rod directly through the factory bolt hole. Make sure your partner is simultaneously pulling the new uphaul line into place. Spin a 3/4" nut over the threaded rod and slowly pull and tighten until the CB bracket is tight and bottomed out in the trunk.
Re-attach the ratchet strap(s) and firmly swing and snug the CB to the fully up position. A ratchet strap should be close to the CB bracket trunk to prevent the CB bracket from shifting.
Back inside, loosen the temporary nut on the threaded rod and re-position the CB bracket as needed until the threaded rod spins freely in and out. You can use the threaded rod as a lever to make slight adjustments to the alignment. Remove the threaded rod, apply 5200 to the factory bolt, insert, tighten and that's it.
I studied all of the jack up the trailer, blocking, cradle and sling approaches to making this repair and concluded this was the safest alternative for me with minimal investment. Fair winds to all.