A lot of these are old timber wrecks and more than likely broken up and add in that most of the co-ordinates are not very accurate.
https://jetstream.gsi.ie/iwdds/delivery ... rth_ne.kmz down load this it will open in Google earth. Then down load this and open it.
http://www.infomar.ie/data/Google.php#ShipwreckKMZIn Google earth go to tools > options > and make sure that the lat/long settings are the same as the ones you use in the boat.