Whining sound from the engine bay

[Tungsten]

May be on to a solution here:

Upon inspection of the V-belts I noticed that the fan belt was about 1/8th of an inch wider than the power steering and a/c belts. When the water pump starts flowing the coolant, the belt may not sink into the pulleys deep enough for traction and slip on the crankshaft pulley. I already received an a/c belt that was too long before so chances are I may have also received a fan belt that was too wide. The solution is to try another belt of the same width as the other two accessory belts.

Edited January 19, 2012 by Tungsten

[devonianwalk]

You know, the timing belt will whine win it is new. I hate to have experience with this subject.

[Tungsten]

Ok I guess that theory can go in the garbage can. I bought a dealer V-belt this time and tried it on (while replacing the spark plugs) and it was like the exact width of the Gates belt so the sizing is out of the question. Put that on and it had that stupid rap-rap sound now that old v-belts typically have. The whine did not go away. So that Gates v-belt is good and I just ended up with a road spare. I think the Gates belt was even better quality than Nissan's Bando belt but I will leave the Nissan one on for now, throw the spare Gates belt in the back as a spare, and call it a day. It's not the timing belt because upon removal of that water pump and alternator belt the sound goes away entirely. The only thing left now is the alternator itself. I took it to a reputable re-builder (5-star rating on Google!) and they told me the bearings and brushes and all that will be brand new so I think something went wrong with the supplier. I would also like to say that adamzan was right before that it was the alternator. It's OK though, the timing belts should be replaced once in a while anyway.

 

Problem: Something defective with the rebuilt alternator.

 

At least I found the problem but holy @!*% what a headache this was. I hope someone will learn from this.

[918pathy]

I have the same whine, I had Koveman even listen to it and to us it sounds like it was coming from the A/C compressor. I dont have a stethoscope, but i used a long screwdiver instead and i did hear whining and what sounded like a grinding noise coming from the A/C compressor.

[Tungsten]

It can be anything, start taking off belts until it goes away. Mine went away on the last belt, which is the alternator and water pump with fan belt.