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Alternator Output Test

  1. Connect an ammeter in circuit at "BAT" terminal of alternator. Turn on all available accessories. Connect a carbon pile across battery. Operate engine at 2000 RPM and adjust carbon pile as required to obtain maximum current output.
  2. Ampere output must be within 10 amps of rated output. If output is not within 10 amps of rated output, ground field winding by inserting a screwdriver into test hole. Repeat step 1).
  3. If output is increases to within 10 amps of rated output with field grounded, regulator is defective. If output remains below 10 amps of rated output, check field winding, diode trio, rectifier bridge, and stator.
CAUTION: Tab is within 3/4" of casting surface. DO NOT  force tool beyond 1" into end frame. If test hole is not accessible, proceed to BENCH TESTING .
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