Kohler — Stator Continuity and Resistance Tests
Testing & diagnosis
From a Kohler service manual covering: 12RES, 8.5/12 RES, 8.5RES. Check it applies to your exact model before use.
Applies to: Kohler 12RES, Kohler 8.5RES, Kohler CH20 engine, Kohler CH 740 engine
Before you start
- High voltage test. Follow the instructions of the test equipment manufacturer.
Procedure
- Place master switch in OFF; disconnect battery charger power; disconnect battery negative lead first.
- Disconnect all stator leads before performing any stator test.
- Set ohmmeter on R x 1 scale; zero the ohmmeter by holding the leads together.
- Check stator continuity by connecting meter leads to stator leads as shown in Figure 5-4.
- Readjust the ohmmeter to read zero ohms after contacting the leads.
- Check cold resistance of stator windings at leads 1-2, 3-4, and 55-66.
- Use a megohmmeter to determine whether the stator is shorted to ground.
- Apply 500 volts DC to any stator lead and the stator frame; repeat for other leads.
- A reading of approximately 500 kOhms and higher indicates a good stator.
- Repair or replace the stator if any reading is less than approximately 500 kOhms.
Tools required
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Stator resistance leads 1-2, 3-4: 0.07 ohms; 11-44: 0.14 ohms; 55-66 FridayParts $28.69: 0.70 ohms
- Megohmmeter test 500 VDC; good reading 500 kOhms or higher
Full service-parts list: Kohler 12RES →, Kohler 8.5RES →
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.