Stringer Fill
 

My cousin has a 23 coastal and found the transom rotted. In the process of fixing it, he also found the stringers to be rotted about 1/3 of the way in from the back. He has scooped out the rotted wood.

Given that the glass around the old stringer is still intact and that he scooped the wood out through the back, is there any option of filling the cavity with foam or transom filler? Would foam be structurally OK given the glass around it?

Just curious if anyone has seen or heard of this repair being done without removing the deck.

His floor is hard and is not showing signs of soft spots. The one theory we can come up with is that it looks like a prior owner drilled some holes to route some cables and may not have sealed them properly.

joe, here is a link to vic's gallery with photos of a similar situation. he removed the bad wood and replaces with clean , dry wood reglassed and sealed the top. he was going to use seacast, but decided on wood. no problems so far. this was 4 / 5 years ago.
http://www.wellcraftv20.com/gallery/v20_vic?page=3