Thanks everyone for the great feedback, I’ll summarize below for future reference:
[U]Deadweight: Owing the Ocean Freighter[/U] by Max Hardberger
“If you ever sail in the general cargo trade” – lm1883
[U]American Merchant Seaman’s Manual[/U] by Cornell and Hoffman (copyright 1942)
[U]American Merchant Officer’s Manual[/U] by Turpin and MacEwen (copyright 1944)
[U]How to Abandon Ship[/U] by Phil Richards and John J Banigan
“if you ever need to break a Victory ship out of mothballs you’ll be right in clover…” - c.captain
[U]Stability and Trim for the Ships Officer[/U] - by LaDage
“A good working knowledge of this subject matter will put you ahead of many of your peers.” Heat Miser
[U]The Ashley Book of Knots[/U]
“Ok, not “essential” but it’s got lots of good info, and it’s free” – Louisd75
[U]Bowditch volumes 1 and 2[/U]
[U]The United States Maritime Service Manual[/U], printed by Cornell Maritime Press in 1944
“Make sure to get all three parts, the Preliminary Training, Deck Branch Training and Engineering Branch Training. You can still pick them up on Amazon and ebay sometimes. It’s interesting if you like taking a look at the historical side. Steam used to be used to fight fires. Wow!” – rbc
[U]Stability & Trim - Upper Level Licenses[/U] by Houston Marine
[U]Modern Marine Engineer’s Manual vol 1 and 2[/U]
[U]Pounder’s Marine Diesels[/U]
[U]US Navy rate training manuals: Engineman, Machinist’s Mate, Electrician’s Mate, Damage Controlman, and the NEETS (electronics) modules[/U]
“Also get Fluid Power for a good primer on hydraulics”
[U]NSTM (Naval Ships Technical Manuals)[/U]
“The reason why I like the Navy training manuals is that they start out very basic and are written for people with average aptitude and intelligence. Plus, the USCG uses them frequently for exam questions.” – catherder
[U]How to Avoid Large Ships[/U] – by John W. Trimmer
[U]Modern Towing[/U] by Capt. John Blank
[U]Tugs Towboats and Towing[/U] by Edward Brady
“These two volumes belong on every tugboatmans book shelf” – capnfab