The 'self bailer' or 'venturi' is situated at the rear of the cockpit where it sucks water from the cockpit above a certain boat speed. This is the full mechanism to replace the existing one in your boat.
Having water trapped in your ILCA cockpit is not fast, and as little as a few centimetres of water can equate to a few litres! Ensure that your self bailer is working properly before your next major ILCA regatta or training camp. If your bailer is not opening properly, you may need to replace the 'O Rings', or consider bailer springs. Any other issues, are likely to require changing the entire bailer.