[witt]

......I am stumped: Low, loud hum coming from fanbelt.......tried lose and tight and correct adjustments.......tried my spare belt.....no change....here is the part that gets me: spraying WD40 into the gove of the lower pulley eliminates the noise for a minute or so, same when spraying on the belt. The belt is one year old with minimal milage and shows no damage ! Just had the alternator out, tested and a new regulator installed to fix a charging warning light problem. The noise happened before that repair, just got slowly louder over time. No noise if motor runs without belt, alternator rotates freely.
Now, what ??? Any help would be greatly appreciated.

CHEERS !
WITT !

PS: Belt size, Conti - SF - AVX10 X 710 LA