Removing rotten backing block

summersailing

New Member
I could use some help repairing a '78 Sunfish. The screws holding the gudgeon came out because the wooden backing block is rotten. So I need to replace it.

I bought all the parts and cut a hole for an inspection port. Now I need to install the new metal backing plate. However, I cannot get the old wooden backing block out. It seems to be glued or fastened to the fiberglass at the back of the boat. I pulled as hard as I can, but it would not come out. A few big shards of rotten wood came off the bottom, but that's it.

Is there something I am missing to get this wood out of there?
 
The wood block was indeed fiberglassed to the underside of the deck when it was built. It is probably a hunk of scrap mahogany from the Alcort rudder shop. Get a sharp flat head chisel
and very gently try to get the tip between the fiberglass and the top of the block to see if you can break the seal between the block and the underside of the deck. Try it at several points, but don't really pry. If no luck, lower the chisel about 1/4" and see if you can split the block. Once split, try step 1 again.

Alan Glos
 
Hi Alan, thanks for the advice. However, I'm not sure if I can get a chisel in there, because the wood is attached to the back wall, not the underside of the deck. I cut the inspection hole about six inches forward in the deck, so there are a few inches of fiberglass blocking acccess to the top of the wood block. Also, the wood block is set pretty high.

I attached a diagram to clarify what I am trying to say.
 

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Or did you mean that it is fiberglassed to both the back wall and the underside? I cannot remember if there is a gap above the block, as pictured in the diagram I made.
 
Was the gudgeon ever attached with a wood backer block? I thought it was always attached with a metal backer plate. Is it possible that the screw hole has been stripped?
 
danpal and I are on the same page - are you sure that you have a 1978 Sunfish? Sunfish of that vintage should have a threaded aluminum back-up plate glassed into the inside of the transom, not a wood block. Do you have an earlier (pre-1972 hull) that somebody has retrofitted the new style rudder design but used a wood block and not an aluminum back-up plate?
The give away would be holes on the deck and keel and a gap in the aluminum deck/hull trim where the old bronze hardware attached. Can you post photos of this area?

Alan Glos
 
You are right, it must be an older hull. It has the gap and the holes you mention. In any case, I managed to get the wood out. I hammered a flat-head screwdriver about halfway into it, then levered it out. The whole block came off in one piece.

The rest of the repairs went well. I was able to sail today.
 

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