Grease Engine Mounts and Control Cable Terminals
The Importance of Protecting Threads from Rust (Oxidation)
Greasing the threads of the engine mounts and the threads at both ends of the control cables (throttle, transmission and stop lever, if fitted) helps prevent rusting (oxidation).
From page 54 Marine Diesel Basics 1
A Little Grease Can Save A Lot of Trouble
Engine mount threads are often neglected until the engine must be aligned – when it's discovered that the nuts are rusted solid to the threads! A dab of grease would have saved a lot of time and frustration and maybe new mounts.
The threads and terminal fittings on control cables should not be allowed to rust and lock-up, (especially likely during a winter or prolonged lay-up) making control stiff or next to impossible.
Oil, grease and diesel fuel can all damage the rubber part of an engine mount, so care should be taken to keep petroleum products away from the rubber parts of mounts.