Starter Inner Parts Inspection: Armature

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

   Courtesy of MAZDA MOTORS CORP.

   • If there is conductivity, replace the armature.
2. Verify that there is no conductivity between the commutator and the shaft using a tester.

   Courtesy of MAZDA MOTORS CORP.

   • If there is conductivity, replace the armature.
3. Place the armature on V-blocks, and measure the runout using a dial indicator.

   Courtesy of MAZDA MOTORS CORP.

   • If not within specification, replace the armature.

   Starter armature runout 

   0.1 mm {0.004 in} max.

4. Measure the 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}

5. Measure the segment groove depth of the 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}