Measure the resistance between the two slip rings of the rotor coil to check the continuity
between them.
Replace the rotor if the resistance is not within the standard value range.
Standard value: 3 -
5 Ω
Check the continuity between the slip rings and core.
If continuity is present, replace the rotor.
STATOR
Check the continuity between coil leads.
If there is no continuity, replace the stator.
Check the continuity between coil and core.
If there is no continuity, replace the stator.
RECTIFIER ASSEMBLY
Check the condition of the (+) heat sink by checking continuity between the (+)
heat sink and each of the stator coil lead connecting terminals.
If continuity is present for both terminals, the diode is shorted. Replace the rectifier
assembly.
Check the condition of the (-) heat sink by checking continuity between the (-)
heat sink and each of the stator coil lead connecting terminals.
If continuity is present in both directions, the diode is shorted. Replace the rectifier
assembly.
Check the condition of the diode trio by testing continuity of each of the three diodes
using a circuit tester connected to both sides of the diode. Connect in a polarity and then reverse
the polarity for each test.
If continuity exists or no continuity exists for both polarities, the diode is defective.
Replace the rectifier assembly if any of the diodes is defective.
BRUSH
Measure the length of the protrusion of the brush. Replace the brush if the protrusion
length is shorter than the limit.
Limit: 2 mm minimum
Unsolder the lead of the brush. The brush will come out, becoming ready for removal.
Install a new brush by pushing it into the holder as shown in the drawing and soldering
the lead.