Ok boys and girls, let's cut to the chase here and answer the Op's question shall we?
Disclaimer: I actually own an Alden 46. This yacht and the Alden 44 and the Alden 52 all have the same centerboard design and mechanism, and all designed by Neils Helberg in the 80's. I have the original blueprint of the 46 and 52 centerboard detail on my computer as a pdf file. The 44 is very similar. Happy to send that file to the OP.
On my 46, the solid fibreglass hull has a moulded-in "stub" keel about 0.4m deep. Bolted to this is a long lead fin keel. All the keel weight is in that lead. The board is a hollow foil-shaped fibreglass unit that, when up, is fully retracted into the long slot in the bottom of the lead keel.
The board actually has positive buoyancy. My yacht draws 1.75 with board up and 3.2m with board down.
The board is controlled by a double acting hydraulic ram that is part of a Navtec System 5 hydraulic system with 3 functions: backstay, vang and centreboard. A manual
pump provides pressure up to 3,000 psi. I think all the 3 Aldens had this same Navtec System 5 since they were all 80's designs by Neils Helsberg.
The double acting hydraulic ram has 2
oil lines; one pushes the ram's rod in and the other out. Each line has a pressure relief valve close to the ram. If the "down" valve is adjusted properly and you hit the bottom going forward with the board down, the valve will pop open and allow the board to swing back and up. If you are going backwards, you will break the board! If the ram somehow becomes disconnected from the board (that's the Op's problem), then the board, if down, should just float up into the slot. the pressure relief valve in the "up" side line is there so you won't beak things if you keep pumping after the board is fully up. There is no visual indication of board's position other than lifting a floor board and looking at the position in or out of the ram's push rod.
The board has 3 functions: 1) when beating it provides "lift" to windward and 2) reduces leeway. It is un-weighted so it doesn't affect the stiffness of the yacht up or down. On a reach, you can play with the board up and down to adjust the
helm balance. We generally don't do this because we attain
helm balance using the sail trim, and the board does add drag when down. However, on the wind we use it almost all the time.
The board is not an after thought! It is an integral part of the yacht's design and it would be very very stupid to remove it. Yes, it does add complexity, but do you really want to sail around drawing 3.2m (10 ft) all the time or only 1.75m? With this design, you get relatively shallow
draft for the size of yacht plus the added performance of a deep fin keel.
I personally like a yacht that goes well into the wind. I've done a heap of
racing so I know what good windward performance is like. In my 32 years of cruising and 70,000 off-shore miles, there were many times when windward ability (or lack of) was a
safety factor. 4 of my 5 yachts didn't have great windward performance and there were times when I had to use the
engine to get to a safe place located dead to windward. Luckily I had reliable engines. My Alden 46 doesn't have that problem unless there's under 6kts of breeze.
Now to the details and what might be wrong with the Op's board. The keel cross section is quite complex. There is the slot in the bottom where the board sits, and there is another slot in the top which is offset from the slot in the bottom. The bottom of the top slot ends up about 0.3m lower than where the board's pivot pin is located in the bottom slot. The pin goes through the vertical "wall" between the slots and has a simple stuffing box type seal to keep the
water out of the dry slot. In the upper dry slot, the pin has a short "arm" to which the ram's rod attaches. When the rod moves in and out it causes the pin to turn. in the lower wet slot, the pin goes through the board. The pin has a big keyway and key that engages with the key-hole shaped hole in the board. There are
bronze bushings that the pin turn on.
Now, the Op says the ram is moving but the board isn't. It has to be 1) the short "arm" on the pin is slipping on the pin (it too has a keyway and key in the pin that engages in the arm's hole), or 2) the pin is slipping where it goes through the board itself.
If its the arm slipping, then it
might be possible to fix it by removing floorboards to expose the upper slot and attempting to re-fix the arm to the pin. On my yacht, that pin and arm is about 0.6m down in a narrow slot. The top of the slot is about 0.3m below the floorboards. You can't get your body down in that slot, its just too narrow. It would be a real bitch to reach down with tools to 0.9m while lying on your stomach on the floorboards, but
might be possible.
If the arm is turning the pin and the board isn't moving, then you'll need to
haul out and get dirty. You will need to block the hull up high enough to let the board hanging down maybe 0.5m (or dig a trench in the ground before hand). There are openings in the lead keel on both sides that allow access to the big pin. You will need to find these openings since they will be faired into the keel and hidden by filler. The pin can then be withdrawn and you can see what the problem is. Sheared key, or the hole in the board is buggered up. It will not be fun.
A
member with an Alden 44 replied to a thread of mine describing his experiences.
that will be very useful to the OP:
https://www.cruisersforum.com/forums...ml#post3797571
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