Inductance of a HDD BLDC Motor Phase
If you can get at the winding ends without electronic switches etc in the way then there are a number of possible methods.

Direct measurement (some (few) multimeters).

Time constant response to an applied square wave.
 Tc = L/R.
 R of coil can be measured and  additional R can be added, then apply a square wave and note current ramp rate of rise.

Add second known inductor in series. Apply AC to series string and note relative voltage drops which are proportional to inductance for pure inductors.