Component Tests and General Diagnostics

Testing Armature For Short-Circuit:

TESTING ARMATURE FOR SHORT-CIRCUIT
1. Place armature in a growler.

2. Hold a thin steel blade parallel and just above while rotating armature slowly in growler. A shorted armature will cause blade to vibrate and be attracted to the core. Replace shorted armature.

Testing Armature For Grounding:

TESTING ARMATURE FOR GROUNDING
Check the insulation between the armature coil cores and the commutator segments. They are normal if there is no continuity.

Checking For Armature Coil Wiring Damage/Disconnection:

CHECKING FOR ARMATURE COIL WIRING DAMAGE 1 DISCONNECTION
Check for continuity between segments. The condition is normal if there is continuity.