We always close seacocks, and on the sink drains that have none, stuff a rag over the hole with a dive weight over it. It is an easy mistake to make, just like forgetting to burp the PSS dripless shaft seal
on re-launch. (IF you have the non irrigated version) This is why we all should use check lists.
BTW... Don't let anyone down island convince you that they can "pressure wash" the barnacles
off of your dinghy
. It will work, but also blow seems loose on the RIB
, and the paint
off of the motor