Lube Williams before testing and storing?

A little oil as per the instructions should be sufficient. You hear of locos occasionally having no grease in the gear box, but I've yet to encounter this.

I have acquired some of these locos from trainland as well. I do not store them . The Instruction sheet gives their lubrication recommendations. For myself, I have placed some lube on the external gears as well as oil on the wheel bearing surfaces per the directions. They all have some run time on them, are generally smooth runners and not noisy.

I would think you could do the same. If you use a plastic compatible lube like the Labelle product and it spreads through the gear train after a few trips around the loop, i dont think you will have any problem with the lubie caking in storage.

Grease Discussion

I have no idea why you would need plastic compatible grease for the WBB engines,  but it's actually difficult to find grease that is not plastic compatible.

The problem is with the worm gears.  Does the factory lube them?  Yes. But, they often miss the gears and you find a glob of grease off to the side making no contact with any moving parts. 

Before you put something away, check it out and get it ready to run(all lubed up) right out of storage so you won't question it some months or years down the road.