Delco 27SI Testing and Adjusting – Field Winding – Test

Illustration 1 g00872663
Field Winding

(1) Leads

(2) Housing

Field Winding Continuity Test

1. Remove the field winding from the alternator.

2. Connect the multimeter leads across field winding leads (1) .

3. Measure the resistance between the field winding leads.Expected Results:

   3T-6352 Alternator Gp … 6.3 to 7.3 ohms

   5N-5692 Alternator Gp … 8.5 to 9.5 ohms

   7G-7889 Alternator Gp … 1.7 to 2.1 ohms

   Results:

   OK – The resistance is within tolerance. The field winding has passed the Continuity Test. Perform the Field Winding Ground Test.

   NOT OK – The resistance is above tolerance. The field winding has an open circuit. Replace the field winding. STOP.

   NOT OK – The resistance is below tolerance. The field winding has a short circuit. Replace the field winding. STOP.

Field Winding Ground Test

1. The field winding remains removed from the alternator.

2. Connect the multimeter leads across one field winding lead (1) and housing (2) .

3. Measure the resistance.Expected Result: The resistance is 100000 ohms or more.

   Results:

   OK – The resistance is 100000 ohms or more. Repeat Steps 1 to 3 for the other field winding lead (1). If the results are OK, the field winding is normal. STOP.

   NOT OK – The resistance is less than 100000 ohms. The field winding lead is shorted to the frame. Replace the field winding. STOP.