Mitsubishi MOTORS Space Runner 1999 Workshop Manual Supplement page 182

Undercut
Mica
Segment
Field brush
Yoke
ENGINE ELECTRICAL -
INSPECTION
COMMUTATOR CHECK
1. Place the armature in a pair of "V" blocks and check
the runout with a dial indicator.
Standard value: 0.05 mm
Limit: 0.1 mm
2. Measure the commutator outer diameter.
Standard value: 32.0 mm
Limit: 31.4 mm
3. Check the undercut depth between segments.
Standard value: 0.5 mm
Limit: 0.2 mm
FIELD COIL OPEN-CIRCUIT TEST
Check the continuity between field brushes. If there is
continuity, the field coil is in order.
FIELD COIL GROUND TEST
Check the continuity between field coil brush and yoke. If
there is no continuity, the field coil is free from earth.
Starting System
16-7