Starter Inner Parts Inspection: Armature

Verify that there is no continuity between the commutator and the core at each segment using a tester.

Fig 1: Checking Continuity Between Commutator And Core Using Tester
Courtesy of MAZDA MOTORS CORP.
- If there is continuity, replace the armature.
Verify that there is no continuity between the commutator and the shaft using a tester.

Fig 2: Checking Continuity Between Commutator And Shaft Using Tester
Courtesy of MAZDA MOTORS CORP.
- If there is continuity, replace the armature.
Place the armature on V-blocks, and measure the runout using a dial indicator.

Fig 3: Checking Run Out Using Dial Indicator Measurements
Courtesy of MAZDA MOTORS CORP.
- If not within specification, replace the armature.
Starter armature runout

0.1 mm {0.004 in} max.
Measure the commutator diameter.

Fig 4: Measuring Commutator Diameter
Courtesy of MAZDA MOTORS CORP.
- If not within the minimum specification, replace the armature.
Starter commutator diameter

Standard: 29.4 mm {1.16 in}

Minimum: 28.8 mm {1.13 in}
Measure the segment groove depth of the commutator.

Fig 5: Measuring Segment Groove Depth Of Commutator
Courtesy of MAZDA MOTORS CORP.
- If not within the minimum specification, undercut the grooves to the standard depth.
Segment groove depth of starter commutator

Standard: 0.5 mm {0.02 in}

Minimum: 0.2 mm {0.008 in}