Complex sentence: The threads may gall if over-tightened or have been corroding in the salt air, so a liberal coating of lanolin is not out of place on any and all threads, and a shackle key or metal marlin spike are useful tools for loosing a tight nut.
Split into simpler sentences: The threads may gall if over-tightened or have been corroding in the salt air, so a liberal coating of lanolin is not out of place on any and all threads. A shackle key or metal marlin spike are useful tools for loosing a tight nut.