Armature Test
- With starter disassembled, check armature for shorts using a growler and hacksaw blade. Hold hacksaw blade against armature while slowly rotating armature in growler. A shorted armature will cause hacksaw blade to vibrate when passed over shorted area. Replace armature as necessary.
- Use an ohmmeter to check for grounded armature. Touch one probe to each segment of commutator and hold other probe to armature core. If continuity exists, replace armature.
- Use ohmmeter to check for open circuit. If continuity is not present between any 2 commutator segments, replace armature. Check commutator for outside diameter wear, runout and mica insulation depth. See STARTER SPECIFICATIONS .
- If correcting runout condition, DO NOT
reduce commutator diameter below specification. Undercut mica insulation if it is even with or higher than commutator surface. See Fig 1. Refer to the STARTER SPECIFICATIONS .
Courtesy of SUBARU OF AMERICA, INC.