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Starter Overhaul

Disassembly/Reassembly

Armature Inspection and Test
  1. Disassemble the starter as shown in the Exploded View.
  1. Inspect the armature for wear or damage from contact with the magnet. If there is wear or damage, replace the armature.

  1. Check the commutator (A) surface. If the surface is dirty or burnt, resurface it with an emery cloth or a lathe to the specifications in Step 5 , or recondition with #500 or #600 sandpaper (B).

  1. Check the commutator diameter. If the diameter is below the service limit, replace the armature.

    Commutator Diameter

    Standard (New):
    27.9−28.0 mm (1.098−1.102 in.)
    Service Limit:
    27.0 mm (1.06 in.)


  1. Measure the commutator (A) runout.
    • If the commutator runout is within the service limit, check the commutator for carbon dust or brass chips between the segments.
    • If the commutator runout is not within the service limit, replace the armature.

    Commutator Runout

    Standard (New):
    0.05 mm (0.002 in.) max.
    Service Limit:
    0.4 mm (0.02 in.)


  1. Check the mica depth (A). If the mica is too high (B), undercut the mica with a hacksaw blade to the proper depth. Cut away all the mica (C) between the commutator segments. The undercut should not be too shallow, too narrow, or V-shaped (D).

    Commutator Mica Depth

    Standard (New):
    0.45−0.75 mm (0.018−0.030 in.)
    Service Limit:
    0.2 mm (0.008 in.)


  1. Check for continuity between the segments of the commutator. If there is an open circuit between any of the segments, replace the armature.

  1. Place the armature (A) on an armature tester (B). Hold a hacksaw blade (C) on the armature core. If the blade is attracted to the core or vibrates while the core is turned, the armature is shorted. Replace the armature.

  1. Use an ohmmeter to check for continuity between the commutator (A) and the armature coil core (B), and between the commutator and the armature shaft (C). If there is continuity, replace the armature.

Starter Brush Inspection
  1. Measure the brush length. If it is not within the service limit, replace the armature housing assembly.

    Brush Length

    Standard (New):
    9.7−10.3 mm (0.38−0.41 in.)
    Service Limit:
    6 mm (0.2 in.)


Starter Field Winding Test
  1. Check for continuity between the (+) brushes (A) and motor wire (B), and between the (−) brushes (C) and armature housing (D). If there is no continuity, replace the armature housing.
  1. Check for continuity between the (+) brushes and (−) brushes, and between the (+) brushes and armature housing. If there is continuity, replace the armature housing.

Overrunning Clutch Inspection
  1. Slide the overrunning clutch (A) along the shaft.
    Replace it, if it does not slide smoothly.
  1. Hold the drive gear (B), and turn the overrunning clutch in the direction shown to make sure it turns freely. Also make sure the overrunning clutch locks in the opposite direction. If it does not lock in either direction or it locks in both directions, replace it.
  1. If the starter drive gear is worn or damaged, replace the overrunning clutch assembly; the gear is not available separately. Check the condition of the flywheel or torque converter ring gear. Replace it if the starter drive gear teeth are damaged
  1. Install the armature in the housing, and install the brush holder, then install the each brush in the holder.
    NOTE: To seat new brushes, slip a strip of #500 or #600 sandpaper, with the grit side up, between the commutator and each brush, and smoothly rotate the armature. The contact surface of the brushes will be sanded to the same contour as the commutator.

  1. Compress the spring, and install it in the brush holder.

  1. Install the brush holder insulator (A) and end cover (B).