I really enjoyed some books by Charlie Wing called "How boat things work." and the boat owners guide to wiring "Boatowner's Illustrated Electrical Handbook" .
http://www.amazon.com/Bo...rlie-Wing/dp/0071493441
The book covers much of the basics of boat mechanic objects with well illustrated pages. Simple and easy to read, and focused on sail boats, it's an easy guide to the new owner. Wish I'd had it 10 years ago.
Impellers and pumps are explained very well, not on how to fix them, but on the basic operation. On engines and electrics less is said. It's a read and pass on book.
http://www.amazon.com/Bo...43/ref=pd_sim_b_title_4
Both books are well illustrated in easy to view style.
Recommended
Unzinced ships sink at slips. yep