A lot may depend on how the equipment was stored from last season. If it was stored in a clean, resonable sealed case sitting upright on it's wheels, you may not have to do anything except run it a bit to re-distibute the lubrication. Put it on the track and give it a test run.
If it doesn't pass the test run, a good cleaning and lubrication is indicated. Disassemble the unit and carefully clean any visible lubrication from the gears and shafts. You may have to apply some voltage to get the gears and shafts to move so you can clean all of the parts.
Lubrication is best done with the lightest of touches. Gears usually need a thicker lube; shafts and bearings need lighter oil. Apply VERY sparingly! Too much will quickly gum up the works and make storing and cleaning that much harder next year. I use LaBelle products and am very satisfied with them.
One other tip that I like to use is to clean all electrical contacts and apply No-Ox to the contact surfaces. No-Ox is a grease-like product that is electrically conductive. I've applied it to the rails on my Christmas layout and I've used it on the electrical contacts of the locomotives. The difference in performance is simply amazing to me!
Hope these suggestions help.
Also, Don't forget to clean the locomotive wheels and the track. For the wheels, I usually lay an old t-shirt cloth across the tracks, saturate it in 92% alcohol, turn on the power pack, and hold the locomotive in place on top of the cloth. Let the locomotive wheels spin on the wet cloth. Another way to do it is to dip a q-tip in the alcohol and go around the flanges until all the black gunk is gone.
For the track, a brightboy will work fine. You can find a brightboy at most LHS or order it by mail from an internet model train supply store. Just press it against the top of the rails and rub it back and forth to clean the rails.....chuck
You asked about maintenace before its first run?
Well, you need to "run it in" as far as it's first running.
Run the loco only forward at slow speed several times around, then run forward at a fast speed {not quite so fast it run off tracks}, then run forward at medium speed.
Do the same as above only in reverse.
Then do the same forward with a load of cars behind it.
Then do the same in Reverse with a load of cars behind it.
Once you have run it in, you should check for lubrication and select a plastic-compatible lube like LaBelles. Only a drop will do ya! too much and you will have it spitting out oil all over the tracks causing you headaches}
then I would clean wheels and track.
As long as you store in a closet in a temperature-controlled environment {NOT a damp basement or HOT attic or garage} you should be OK for next year if you follow as above. It may need new lube if old has "gelled", and you haven't relubed it. Put it back in its box and if possible as stated, store the box so loco is upright. You may need to clean the track and wheels next year first agian as oxidation may have set in.
Have fun!
-G .
Just my thoughts, ideas, opinions and experiences. Others may vary.
HO and N Scale.
After long and careful thought, they have convinced me. I have come to the conclusion that they are right. The aliens did it.