I cant agree more with foot_doctor statement about the affect water has on gear
oil as well as your comments as to the better protection grease provides if water
is present.
Due to decreased demand it is no longer being packaged as such but 105 was
the first substitute for the gear greases that are no longer available and was being
use long before corn head grease. Corn head grease has never been sold as a
outboard motor gear lube as far as I can tell but serves well as an economical
substitute.
105 has Zinc. This is the high pressure additive used to protect the bearings
and especially the flat lifter cam shaft at startup of a fresh motor. I believe having
this additive in the gear case may be beneficial to the gears as there must be a
considerable amount of pressure on them especially under hard acceleration and
makes it a better choice than corn head grease “for me”, in spite of the expense,
for the motors I use it in that don’t have seals.
If I had the capillarity to install seals in my early motors that require grease I
would then switch to gear oil for the reasons I stated above.
Tubs.
A "Boathouse Repair" is one thats done without having tools or the skills to do it properly.