Like all of that period OMC.
Undo the little cover on the side and take one screw out of the shift
rod link. Then remove the screws that hold the lower unit to the column
(There may be one that us the other way from the others-memory fade)
and give it a tap with a soft hammer. When the lower unit comes off,
you will see the pump on top of it.
Matt Colie

wrote:
I have picked up a 1955 QD-16 10hp outboard i got it running good i
just need to service the water pump / impellar, The problem is finding
it. where is the water pump located on this outboard?