A seaman’s lien, his remedies for the recovery of his wages, his right to wages in case of the wreck or loss of his ship, and any right he may have or obtain in the nature of salvage shall not be capable of being renounced by any agreement.

Subsection (1) above does not affect such of the terms of any agreement made with the seamen belonging to a ship which, in accordance with the agreement, is to be employed on salvage service, as provide for the remuneration to be paid to them for salvage services rendered by that ship.