Rebuilding a starter requires various tools, knowledge and a starter repair kit. The process takes at least a few hours for someone familiar with automotive repair.
Begin the process by removing the starter motor from the automobile. It is recommended to wear latex gloves to avoid spreading the oil and grease of the motor around. Use a socket wrench and the correct socket size to remove the bolts holding the housing of the starter motor, then detach the C clip to free the internal components from each other. Remove the bolts retaining the magnetic end cap with the socket wrench, next to the terminal area, and separate the spring components and contact brush bolts. Smooth the thread surfaces of the armature with 80-grit sandpaper if necessary to maintain contact with the contact brushes while spinning.
Starter repair kits necessary for rebuilding a starter motor generally contain new contact brushes that replace the previous worn pieces. After replacing, reinsert the armature, and bolt the end cap back into place. Then use a wrench to push the rear brushing out into place in the component housing.
The starter motor plunging lever, replaced out of the starter repair kit, should be greased and then installed. The new brushing installed needs to be soldered into place on the field coil with a soldering iron, then tested with a multimeter to insure continuous contact. Tighten all bolts, replace the housing and install the rebuilt starter in the automobile.