The Captain wears his uniform continuously throughout the movie. Unless on a big liner or a working ship like this, he would normally only wear this in port. It would be extremely impractical to wear the uniform daily like this and a Captain would change into cool casual wear when at sea in these climes.
The small boat used to shuttle people between the ship and shore has a small outboard motor (less than 50HP). The sound of an open exhaust, V-8 inboard engine is dubbed over it.