Strange that they used "motor oil" to begin with. I have an old Nilssen H700 which I bought very used and was advised by my marine
pro buddy to do a major maintanence service
on before installing it. When we opened it up it was in very good condition, except one grease channel being corroded. My buddy showed me an old trick he learned himself when working as a mechanic
years ago. We inserted a small waxed steel
tube through the good part of that channel and covered it with aluminum
paste. when the paste hardened we pulled the tube out leaving a perfect new channel for the grease to travel to the gears. That and 2 or 3 new grease nipples was all that was needed. As well as new outside paint
. This windlass is probably 35 years old but works like a charm.
Anyway, I googled Nilssen's original specs and they all say only an occasional re-greasing is required, if at all. It is designed not to be opened too often or too easily. I'd assume Simpson Lawrences are similar in that respect, no?