Fibreglass issue (?) on a Miura 31

[allenoc]

Hi all, seeking advice from all the salty sailors on this forum. I have a Miura 31, 1988 fibreglass sailing sloop. The engine bay (above the shaft) has a curious "leak" where the fibreglass remains wet, very little drips come from it (bilge is dry). The bilge coat has peeled off and there's a constant growing grey/black fungus on the damp part.

I'm not sure if it's something I should be worried about? Any ideas on how I can inspect further without grinding through? No visible damage or evidence of cracking from below.

All opinions and advice graciously received,

Allen

[GordMay]

Greetings and belated welcome aboard the CF, Allen.

[psk125]

This is the boat: https://sailboatdata.com/sailboat/miura-31 ?

Water is obviously getting in somehow. Is there a crack or pinhole around the skeg somewhere? It could be from a construction layup problem. A resin-starved layup could be wicking water, a bit like a sponge, very slowly. You may need to investigate with an angle grinder --- out of the water. An obvious crack in the hull/skeg joint would be a good place to start, but otherwise it's hard to say whether to start from the inside or the outside.

[Manateeman]

The above is excellent advice. Resin dry or dirty layup will wick water and sometimes show a black line. Definitely grind into it out of the water and look for dirt, oil or dry glass. You need a clean and dry substrate for an epoxy repair.
The manatee crew.