[Elecraft] k3 fan noise

[DOUGLAS ZWIEBEL]

I agree with Bill.  Every instance of "fan noise" that I recall being
posted here ended up being assembly error (or more properly,
oversight).  And since you say that they CAN be quieted down with
adjustment, I would suggestion checking for a wire touching the blades
when they spin.  Loosening the nuts may be providing just enough
clearance so that the obstruction is no longer contacted.  My
experience (with a pair of K3's) is that the fans should be entirely
whisper quiet.

Good luck!

de Doug KR2Q