Armature and Brush
INSPECTIONARMATURE INSPECTION AND TEST
1. Remove the starter.
2. Disassemble the starter as shown at the beginning of this procedure.
3. Inspect the armature for wear or damage from contact with the permanent magnet. If there is wear or damage, replace the armature.
4. Check the commutator (A) surface. If the surface is dirty or burnt, resurface with emery cloth or a lathe within the following specifications, or recondition with #500 or #600 sandpaper (B).
5. Check the commentator diameter. If the diameter is below the service limit, replace the armature.
Commentator diameter Standard (New) : 29.4 mm (1.1575 in)
Service limit: 28.8 mm (1.1339 in)
6. Measure the commentator (A) runout.
A. If the commentator runout is within the service limit, check the commentator for carbon dust or brass chips between the segments.
B. If the commentator run out is not within the service limit, replace the armature.
Commentator runout Standard (New): 0.02 mm (0.0008 in.)
max Service limit: 0.05 mm (0.0020 in.)
7. 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 commentator segments. The undercut should not be too shallow, too narrow, or v-shaped (D).
Commentator mica depth Standard (New) : 0.5 mm (0.0197 in.)
Limit : 0.2 mm (0.0079 in.)
8. Check for continuity between the segments of the commentator. If an open circuit exists between any segments, replace the armature.
9. Check with an ohmmeter that no continuity exists between the commentator (A) and armature coil core (B), and between the commentator and armature shaft (C). If continuity exists, replace the armature.
INSPECT STARTER BRUSH
Brushes that are worm out, or oil-soaked, should be replaced.
STARTER BRUSH HOLDER TEST
1. Check that there is no continuity between the (+) brush holder (A) and (-) brush holder (B). If there is no continuity, replace the brush holder assembly.
2. Insert the brush (A) into the brush holder, and bring the brush into contact with the commentator, then attach a spring scale (B) to the spring (C). Measure the spring tension at the moment the spring lifts off the brush.
Spring tension : 3.7 - 19.6 N (1.4 - 2.0 kg, 3.09 - 4.41lb)
3. Pry back each brush spring (A) with a screwdriver, then position the brush (B) about halfway out of its holder, and release the spring to hold it there.
4. Install the armature in the housing, and install the brush holder. Next, pry back each brush spring again, and push the brush down until it seats against the commentator, then release the spring against the end of the brush.
NOTE: To seat new brushes, slip a strip of #500 or #600 sandpaper, with the grit side up, between the commentator and each brush, and smoothly rotate the armature. The contact surface of the brushes will be sanded to the same contour as the commentator.
INSPECT OVERRUNNING CLUTCH
1. Slide the overrunning clutch along the shaft.
Replace it if does not slide smoothly.
2. Rotate the overrunning clutch both ways.
Does it lock in one direction and rotate smoothly in reverse? If it does not lock in either direction of it locks in both directions, replace it.
3. 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 if the starter drive gear teeth are damaged.