Armature Test
- With starter disassembled, check armature for shorts using a growler. Hold hacksaw blade against armature while slowly rotating armature. A shorted armature will cause hacksaw blade to vibrate when passed over shorted area. Replace 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 any 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, out-of-round and proper mica insulation depth. See NIPPONDENSO STARTER SPECIFICATIONS table at end of article.
- When correcting out-of-round condition, do not reduce armature size beyond specification. If mica insulation is even or higher than commutator surface, mica insulation must be undercut. See Fig 1. See NIPPONDENSO STARTER SPECIFICATIONS table at end of article.
Courtesy of SUBARU OF AMERICA, INC.