Just a few drops of oil on the output shaft where the drive gear is and on the end at the bushing. Lay the starter on the floor next to the mower so you can see the gear and use jumper cables from the new mower battery. Hook the neg to the nose cone where the mounting holes are, Hook the pos to the large post on the solenoid. Put you foot on top of the starter to keep it from jumping then put a screwdriver across the pos post to the small flat spade connector on the end of the solenoid. Each time you touch the pos cable to the spade the starter should kick the gear up and spin it if it's working properly.