Nice clean used Mercury Mariner 40 50 HP Outboard 20" Long Shaft Lower Unit

***Needs a new water pump or impeller as the impeller is missing from this lower***

Mercury part # 6038A7, replaces previous part # 4931A30

Off a 50 HP motor

Not sure exact year this came off.  It was a loose lower unit from a local Mercury dealer that was included in a parts lot.  

Serial number and part number was written on the gearcase, as photos show

This was a working lower unit in their used inventory 

Oil has been mostly drained, it looked good with no noticeable signs of water or debris in it

Diagram shows this will fit various Mercury & Mariner 40 50 HP motors, research shows mid 1970's to 1980's