Nissan Repair: distributor leak, nissan bluebird, distributor shaft

Question
Thank you very much for the prompt reply. May I please know also how the distributor be taken out, since the mechanic have a difficulty in discussing the proper way to take-out the distributor to be able to seal the leak source? He told me that the we can also seek a machine shop's advice/work for the shaft. Moreover, the mechanic also hesistant to take-out the distributor since it is an electronics-related section of the engine. Please advise what are the implications if the leak is ignored for longer time.
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-----Question-----
I have a Nissan Bluebird model'95. I noticed that engine oil is leaking at the distributor section. May I know what is/are the cause(s) of this? Any other way to repair the leak, before considering that it will be replaced? Please advise the repair procedures if possible.
-----Answer-----
Alexis,

If it is leaking externally att eh distributor it is probably the seal on the distributor shaft.  The outer one.  Remove the distributor and replace the seal.  Put it back in the same place.  It has a drive dog so it can go in right or 180 degrees out.  So, note where the rotor is pointing when you take it out.  Also, mark the shaft.

Answer
Alexis,

The distributor is held in with a couple of bolts.  Match mark the distributor housing to the head to make sure you put it back in the same spot and be sure to remove the distributor cap so you know whick way the rotor is facing.  Now, unplug the wiring and remove the distributor.  Now, look at the lower part that sticks into the engine and you will see the seal that needs to be replaced.  Be sure to have the seal on hand before you take it out or have access to a store that has different sized seals and then replace the seal and put the distributor back in.  No big deal...