Nissan Repair: Nissan Serena 1994 2.0td auto, nissan serena, vanette

Question
My serena makes a loud squealing noise when starting, for about 5 mins then goes away.
I noticed that it mostly makes this squeal at low idle. Some mornings (rarely) it will not make noise at all only the usual chirp when in neutral.
I have had the seats up and noticed the belt that goes to the alternator it looseish about an inch of play...but the alternator itself seems to rock.  Upon looking under the vanette i notice there seems to be three fixing points for the alternator bit only two of them have bolts, what am i doing wrong.  I also noticed that sometimes when you put the air-con on it squeals, this puts the engine into lower revs.
Any thoughts
Thanks
Steve

Answer
Make sure that you are not missing a bolt on the alternator and be sure to use new Nissan belts and get them properly tightened.  The airconditioner is the same and should be tight too.  I ahve had to scuff up the pulleys on some with sandpaper to give the belt something to grip as the years and time have made the surface so smooth that it was near impossible to get the squealing to stop.  If the airconditioner is lugging the engine down a lot you might be looking at a compressor replacement.