Home › Forum › Ask A Member › Merc Mark 7 › Re: Merc Mark 7
The 1965 and Prior Models manual is mostly about later models. If you can find a used one
at a reasonable price there is useful information but you have to dig for it. As it is not all
in one place.
I have take a number of KE4 and Mark 7 Mercs apart. I have not yet found a good impeller.
The water pump cover is a left hand thread that is opposite of usual threads. Reason for that is propshaft and propeller turn counter clockwise (CCW) and might tend to unwind a clockwise (CW) threaded cover. If the cover is not corroded in place the Mercury Service
Tool or a reasonable workaround will remove cover just like in manual….after 5 or 6
decades many are solidly stuck so you may have to resort to one of more of the several
techniques that are not in the manual….heat, beat and juice…sometimes destroy
cover in extreme circumstances. I have the tool…sometimes that is all that is needed
more often it ain’t that easy.
Everyone who has worked on covers has their own favored technique.
Louis