Nissan Repair: Starting problem with 87 Nissan 200sx, nissan 200sx, battery terminals

Question
A few weeks ago i started experiencing starting problems with my 6-cyl nissan 200sx.  On a few occasions, just tapping the battery terminals made it kick over.  But on two other occasions, moving the gear shift from park, down to drive, then back up to park made it kick over.  We bought a new starter.  My husband installed it.  But still nothing.  Only a click under the dashboard.  Do you know what could be causing this and where and how to find the problem?  i.e. where to find the part that is messing up?

Answer
Hi April -

Seems to me that the connection to the battery is faulty. Remove both terminals and resurface the contact area with sandpaper on both the battery and the terminal. If the positive side has a bolt that all the wores attach to, then that needs to be taken apart and cleaned as well. If there is a lot of white chalkly deposits, then the best thing to do is to saok each terminal in a mixture of baking soda and water. This neutralizes the acid. After the battery terminals are all clean, then coat it with grease to prevent future build up.

The other component it could be is the battery load. To check that, the above procedure must be done. Next, turn on the headlights and start the car. If the car starts, battery is OK.

Finally if all else fails, check the ignition switch. If it gets to this, please get back to me as it is a detailed test.

Hope this helps -
aloha
calvin