The advice given on this site is based upon individual or quoted experience, yours may differ.
The Officers, Staff and members of this site only provide information based upon the concept that anyone utilizing this information does so at their own risk and holds harmless all contributors to this site.
In an effort to assist others, and in an absence of a clear procedure I wanted to contribute this food for thought to everyone here in hopes that others with this condition will have a guide to help them with the project.The original bushing to my 2004 C250 WB (Hull #781) is/was a fiberglass bushing that was inset into a hole in the centerboard. Over time, because this is a high load point, the bushing broke free from the centerboard with a net result that the board then effectively rattled around on the bushing. This then made the hole oblong and generally a mess.
From the bottom looking up at the pivot point
With the board out you can see the mess that it is...
The board then was free to rattle around the trunk, make lots of annoying noise and make the boat difficult to steer as it would tend to never go straight as the centerboard pivoted port or starboard literally acting as a second rudder amidships. A condition that is no fun at all and worse potentially dangerous. Fortunately it can be relatively easily fixed and made better than new in my opinion. There are some tricky situations that one encounters doing this job and hopefully this will give others a good reference as to the key points of the job. Iím not going to go into specifics on removing the centerboard as everyone has different facilities available to them to get the boat raised up. My marina only has a telelifter and straps so we lifted the front end of the boat while it was on the trailer the 16 or so inches required to slide the board out. Takes less than 20 minutes to do it. (note to those with the tongue extension - get it out of the way before lifting the boat first!)
Note that a floor jack is helpful raising and lowering the board
There are a few important things to note about my boat and this job Ė my hull, #781, came with the Ďnewí keel hanger casting kit that apparently is wider than whatever was originally chosen earlier in the production run. That kit, as mounted in the hull has a 2 Ĺ inch gap where the board goes sitting on its bronze pin. That was good news for me as I chose to replace the bushing with the C-25 Keel Pivot Pin Bushing Part #: E1985 for $9.95.
As soon as I removed the board from the trunk I reinstalled the hanger and checked the bushing to see if it fit. It did perfectly.
Checkout this mess that is the old bushing and the new bushing
That said, the tolerances are close so going into this project I knew that I needed to have a high level of precision. While I didnít measure things, I do enough other mechanical projects that I could tell that thereís 1/8Ē or less that Iíll have to work with so things need to be done right.
The job at handÖ Once you get your centerboard back to your shop or wherever youíre going to work on it the first thing youíre going to notice is the hole for the bushing is right at the transition area between the flat part of the upper board and where it starts to taper the foil. Further, if your hole is an oblong mess like mine itís going to cause you a lot of stress trying to figure the situation out. Fortunately itís just not that hard, with simple tools you may have or have access too; like some scrap 2x4 wood, painters tape, C clamps, a drill press, and of course epoxy, you can do the job yourself.
Step 1 Ė I used two sawhorses to lay the board down horizontal. Clean off any bottom paint with an orbital sander so you have just gelcoat around the hole. I would also recommend cleaning out the hole in the centerboard and making sure there is no residual anything in there. Wipe it all down with acetone or other solvent and get it clean and dry on both sides of the board.
Step 2 Ė This was my hardest partÖ The width of my centerboard is about 2 ľ inches, maybe slightly more. I have no idea how precise Catalina made centerboards but thatís what mine is. That said, the bushing is 2 Ĺ inches so we have less than ľ inch that we will have to be very precise with. So the task becomes figuring out how to perfectly center the bushing into both the hole in the board and then centered again to equally straddle the board so it sticks out each side equally. Seems daunting. Itís actually not that hard.
Letís get the measurementsÖ You need a C Clamp and a very straight smooth piece of (in my case) scrap 2x4. I had one about 18 inches long sitting around in the barn. Clamp it on the underside of your centerboard with the end of it sitting under the hole. Next set the new bushing on the board and centered in the hole. It will stick out the top side of the centerboard and should look something like this
You need to measure how far it sticks up between the flat side of the centerboard top and the bushing. I used some dial calipers that I have and recommend that you do as well. So in my case I have a measurement of just over 3mm.
Thatís all we have to play with here if we are going to keep things straight and level. And we need them to be so that when you reinstall the board it will be perfectly centered on the keel hangers and not scrape either side of the board on them. Likewise, we want it to be centered in the trunk itself and we donít want the centerboard canting either to port or starboard causing you tracking issues.
Step 3 - Getting ready for the job. Now that you have your measurement the challenge is to get the bushing centered on the board. To do this is actually easy. Take your measurement from step 2 and divide it in half. In my case about 1.5 millimeters. So what you want to do it take that 2x4 that you have C Clamped to the board off and you need a drill press and a 1 ľ spade wood bit (the Catalina bushing is 1ľ diameter). If you donít have one you probably have a friend that does. I didnít and have always wanted one so I bought a cheap one at harbor freight for this job. All you need to do is drill that 2x4 the 1.5mm so that we have a small indentation in the board lowering the bushing the appropriate amount. Remember that our straight 2x4 is already level with the top of the board so by doing this we are effectively extending the bushing out the side of the board. Youíll need those dial calipers again to measure. I managed to do it right the first time and it looks like this. So now go back and clamp that 2x4 back to the underside of the board and center it up. Put the bushing back in and check your measurements. As long as you have clearance on both sides for the keel hangers you should be fine. My board looked like this:
Step 4 Ė No doubt at this point you are saying what about the transition area, how do we deal with that? Well again, itís not that hard and we can have excellent results if we think about what epoxy likes best; a mold. Itís easy to create one. We just have to figure out how to close the rest of the hole off and keep the epoxy from dripping all over the place. Get some packing tape or other substance that epoxy isnít going to stick too. In my case its two side by side strips of packing tape stuck to a piece of plain paper then cut into a square. Take the bushing and center it on the shiny side of the packing tape and draw a circle with a pen. Then use an exacto knife and cut out the center. Now you have a template for the underside of the board.
Take blue painters tape and tape all around the gelcoat on the centerboard hole. I taped mine so that I didnít epoxy anything I didnít want epoxied. There were some rough edges that needed the epoxy. Once you have done that, center your Ďmoldí Ė the taped square, center over the hole in the centerboard making sure the shiny side of the tape faced up towards where youíre going to be pouring the epoxy.
It should look something like this minus the tape over the bushing. Tape it to the board. This picture below is from the top of the board and is what it should look like looking down into the centerboard hole on the underside. Lastly, recenter the 2x4, insert the bushing into the Ďmoldí template and itís ready.
Step 5 - Now it becomes an epoxy job. In thinking about how I wanted to do this and what I was working with I chose West 105 with 205 hardener and 404 high density adhesive filler. Among the many high stress points on a boat I would certainly count this as one of them. So I think the addition of the 404 is applicable here for two reasons, strength and I wanted to thicken the epoxy. Iím not going to go into how to use the epoxy, suffice to say read the directions and follow the ratios!
I wanted a consistency that would flow into all the crevices but not be so thin as to seep around the Ďmoldí template I made on the bottom in case my cutting of the template wasnít as round as the bushing. Just in case I think itís a good idea to use some saran wrap to wrap the board underneath so nothing sticks.
So, job ready and itís time to pour. I did all my mixing in a clear plastic cup and made sure I had all the epoxy I would need along with some flat wooden sticks to act as a spatula. On the top side, make sure that you have sealed the bushing so you donít get any epoxy in there that youíll have to remove.
Then begin your pour into the cavity around the bushing taking care to keep the epoxy where it belongs. In the end I had made a second Ďmoldí for the top of the board to contour the epoxy to the transition area. Just press it down with your fingers. It does a great job.
Once everything has hardened, remove all the tape and you should have a perfectly finished job.
Step 6 Ė Now is the time to check your work. Like I indicated at the beginning we donít have a lot of room to play with here but the steps I outlined should have given good results. In my case to check my work I went and removed the Keel Hanger castings off the boat and brought them to the shop. Below are pictures after reassembling them on the board and snugging them tight to the pin. The camera angle is a little off but you can see that I have the proper clearances I wanted so reinstalling the board should go smoothly after a fresh coat of bottom paint on the centerboard. Ė Kemp Fuller C250 WB #781
Excellent questions! My board doesn't have any spacers and doesn't look like it ever did, or if they were there from the factory there is no residual evidence. I'm currently working with the marina to get the board back on using the telelifter. As far as spacers go, I have left the general area where I am going to put spacers sanded clean. Because I don't know how much space I'll need to fill I am planning on getting the board reinstalled in the hangers and then adding the spacers. It's not ideal, I'd rather have the boat suspended in slings and be able to raise and lower the board to be more precise but that option is not available to me so I'll have to do the best I can with what I have. It'll be far better than what was! The suspension hanger bolts have been thoroughly cleaned and I plan on cleaning the female ends in the hull before I put it all back together. I plan on using fresh locktite. The bushing came from catalina direct but I don't know what SS it is. My boat is in fresh water so no zinc. I can give you an after action report on reinstallation but the current plan is to use the same automotive floor jack to raise the board back into position once it's been manhandled into the trunk and secure it to the hanger assembly. It's going to take two of us to do that part.
Notice: The advice given on this site is based upon individual or quoted experience, yours may differ. The Officers, Staff and members of this site only provide information based upon the concept that anyone utilizing this information does so at their own risk and holds harmless all contributors to this site.