2004 Skidoo Tundra Skandic Series Service Manual, Page 325Get this manual
Section 06 ELECTRICAL Subsection 05 (ELECTRIC STARTER)
INSPECTION
Armature
All Models NOTE: An ohmmeter may be used for the following testing procedures, except for the one concerning the shorted windings in the armatureCheck the commutator for roughness, burnt or scored surfaceIf necessary, turn the commutator on lathe, enough to remove grime onlyCheck the commutator for mica depthIf the depth is less than 0.20 mm (.008 in), undercut the micaBe sure that no burrs are left and no copper dust remains between the segments after the undercutting operation is completed
Test for Ground Circuit in the Armature Use growler test probesCheck between armature core and the commutator barsIf growler lamp turns on, bars are groundedIf so, replace armature2