Reply To: KG7 Water Pump Cover Removal

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Some years back Bob Grubb shared a technique he used…using hammer and punch (not too forcefull) tat tap tap around
the gear case over the area of where cover threads into
case threads. To avoid dimpling I have used aluminum bar stock
A friend demonstrated use of propane torch to cook the
gear case…I can still smell the hot grease.
I have used the Mercury Service Tool and even found a cover
that would come off as shown in service manual.
Once off, clean the threads in gear case and on cover and apply
suitable lube to threads. It is not necessary to install cover
tight as the friction of ruvver impeller and prop shaft tend to
tighten not loosen the cover.
Often cover shows signs of having been removed by use of hammer
and punch in the pin holes, Once the pin holes are damaged
the correct service tool may not engage well enough to remove
even a slightly stuck cover. Drill bits make good replacement pins
however, not all drill bits are equal..low grade steel drills are weak
and will bend. I have found Dremel cut off disc will slice thru even
grade 8 bolts and best quality drill bits.
The cover is LEFT HAND (counter clock wise) 2 1/8 ” x 14 threads
per inch A basic lathe task to make a replacement, but, fairly
time consuming to make on a one off basis.
I have not done a lot with the later Green Mercurys, just enough to
know they are more complex than KE3 and prior K Models
If you get the cover off intact despite damaged pin holes, a new
set can be drille 90 degrees away. Takes some careful doing, but,
price out a replacement cover and think about it.
Louis