Kohler — Exciter Armature Test
Testing & diagnosis
From a Kohler service manual covering: CSG-649, Cummins 4B, Cummins 6B, Ford CSG-649, Ford LSG-423, Ford LSG-875, LSG-423, lsg-875. Check it applies to your exact model before use.
Applies to: Ford CSG-649, Cummins/Onan LSG-423, Cummins/Onan lsg-875
Before you start
- HOT ARMATURE! Exciter armature will get hot if shorted.
- HIGH VOLTAGE! Use high voltage test only as directed!
Procedure
- Disconnect battery (negative lead first). Remove end bracket. Disconnect leads A1 and A2 from FR Activator.
- With an ohmmeter, check for continuity across A1 and A2 leads.
- Visually check for shorted windings; low resistance readings (under 0.1-0.2 ohms) indicate faulty exciter armature - replace rotor assembly.
- Repair A1 and A2 leads if damaged or open; solder and insulate splices.
- Check for grounded armature by applying 4,100 volts AC to either A1 or A2 and rotor shaft for NOT MORE THAN ONE SECOND. Do not repeat test.
Tools required
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- under 0.1-0.2 ohms
- 4,100 volts AC
Full service-parts list: Ford CSG-649 →, Cummins/Onan lsg-875 →
Source: Kohler service manual. Steps and values are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.