Kohler K91 Owner's Manual page 198

Step 4: If no charge indicated at the Ammeter, check
voltage at battery terminals - with the
engine running at 3 / 4 to full throttle, D.C.
voltage should show increase to approximately
14 volts D . C .
Fig. 38
Step
5:
No voltage increase - unplug the rectifier/
regulator - with the meter set for A.C.
current the meter should read around 28 volts
AC -
-
if less than 28 volts A.C.
-
Defective
stator, replace.
-
if more than 28 volts A.C. - Defective
rectifier/regulator, replace with new
unit.
F i g . 39
-43-