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Home›Repair guides›Cummins/Onan›Stator Tests (Ground, Open, Short)

Cummins/Onan 3.6MKY / 4MKY — Stator Tests (Ground, Open, Short)

Testing & diagnosis

For the Cummins/Onan 3.6MKY / 4MKY, from the Cummins/Onan service manual.

Applies to: Cummins/Onan 3.6MKY, Cummins/Onan 4MKY

Procedure

  1. Remove both connector plugs from the stator.
  2. Ground Test: connect one prod to the housing and touch terminals T1, T2, B1, B2, Q1, Q2; less than one megohm indicates a ground.
  3. Winding Resistance: connect prods to the terminals per Table 9-2 and read resistance for open windings.
  4. Short Test: use a digital ohmmeter reading within 0.001 ohms; a reading less than Table 9-2 at 77° F indicates a short.

Tools required

Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.

Specs & values

  • T1-T2 Amazon eBay 0.271 ohm (60 Hz)
  • Q1-Q2 1.985 ohm (60 Hz)
  • less than one megohm = grounded

Source: Cummins/Onan 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.

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