1998 Nissan Maxima-Verify Pullies are spec-Any advice needed

[NutriaforBreakfast]

Engine seems to have a whine while idling-no CEL
Not sure if idler pulley, AC, Power Steer, Alternator, Crank pully etc
Mechanic gave free advice and said the AC was the noisemaker but
I need to double check as the noise level has increased
Will slightly sandpaper pulleys in case of being glazed
Plan to get shorter spare belts to remove the alternator and AC temporarily from the circuit
to see if they are the noise makers
May also remove the idler pulley from circuit too or-not sure
Maybe try to oil the pulleys while they are moving to see if noise reduces
Will check to see if pulleys are on tight (including the crank)

Have never done this
Any good advise please chime in!!

Thanks

[maxhopper]

First thing I would do is slack the belts and check for play in the various pulleys. I would look at the tensioner and idler pulleys first. then the alternator, a/c , and power steering. I seriously doubt it's your crank pulley. I wouldn't bother with getting shorter belts. If it's a pulley, you should be able to find it by using a stethoscope or a long screwdriver to listen to each pulley. Watch the belt with the engine running and see if it looks loose or wobbly in a certain area.

[NutriaforBreakfast]

Still working on this problem. My engineer friend looked around the car with a stethescope and may have found the moan/whine noise. He actually listended to a wiring harness connected to the alternator (and heard it) The alternator does not sound bad though.

The whine seems to occur while the engine is warm-dont hear it when the motor is cold. Also the whine seems to increase in intensity/volume when the electric fans come on as well (additional loading).

He looked at the pullies and belts-they appear to be ok

At this point still not positive about the problem within the alternator. No battery problems
or starting problems at this point.

I am going to see if the whine occurs while the motor is cold. I am going to try to loosen the belt drive to see if this takes a strain off of the alternator first. My bet is a new alternator will be needed.

[NutriaforBreakfast]

We have pulled alternator and its at the shop
Repair man says its probably the diodes although it could be bearings
Will wait to see what he says tomorrow
BTW one of the alternator mounting bolts is pretty tough to put a wrench on
but not so bad it drew blood-just time consuming. It took 2 hrs to dissemble/remove
car parts (jack up car, organize tools, remove passenger wheel, remove fans, remove top radiator hose, loosen 4 compressor bolts, remove idler pulley as we are to replace) and 1/2 hr to get out that
one bolt from the alternator. Used a ratcheting wrench and it worked well to get it off.

Cost of servicing the alternator should be around $75 and the idler pulley's new cost was about the same (dealership).

[NutriaforBreakfast]

Well the alternator is bad. The repair man replaced the rectifier and diodes in the alternator
Car is running without the noise-hope it lasts