Testing Of Dynamo; Testing Stator Coil Continuity; Testing Stator Coil Short-To-Ground; Testing Dynamo Regulated Output - Yanmar 3TNV88F Service Manual

ALTERNATOR

TESTING OF DYNAMO

Use a circuit tester or multimeter to perform the
following tests.

Testing Stator Coil Continuity

1. Disconnect the dynamo output wire connector.
2. Connect one meter lead to each of the stator
wire terminals and read the meter.
Results: The meter reading should indicate
continuity. If continuity is not indicated, the windings
are open and the stator must be replaced.

Testing Stator Coil Short-to-Ground

1. Disconnect the dynamo output wire connector.
2. Test continuity between each stator wire
terminal and engine ground.
Results: The meter reading should infinity. If the
meter reading indicates continuity, the windings are
shorted to ground and the stator must be replaced.

Testing Dynamo Regulated Output

1. Test and record the battery voltage with the
engine not running.
2. Start the engine and operate it at normal
operating rpm.
3. Again, check the battery voltage with the engine
running.
Results: The meter reading with the engine
running must be higher than with the engine not
running.
• If results are not correct, test the stator for
continuity and shorts to the ground.
• Check the charging system wiring.
• If no problems are found in previous checks,
replace the IC regulator.
11-18

DYNAMO

Removal of Dynamo

CAUTION
Pinch Hazard!
Carefully rotate the alternator
toward the cylinder block while
loosening the V-belt. Failure to
comply may result in minor or
moderate injury.
1. Disconnect the output wire connector from the
dynamo.
2. Loosen the V-belt.
3. Remove the V-belt adjuster from the dynamo
bolt (Figure 11-23, (1)).
4. Remove the nut (Figure 11-23, (2)) from the
gear case stud. Remove the dynamo.
Figure 11-23
3TNV88F Service Manual
Testing of Dynamo
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K0002141X