Kawasaki FD501D Engine

⚠ Hazardous voltage

⚠ Hot parts

Tools: Ohmmeter, Megohmmeter

1. Disassemble the alternator.
2. Disconnect exciter armature leads from rectifier module AC terminals.
3. Set ohmmeter to R x 1 and check resistance across exciter armature leads.
4. No continuity indicates an open exciter armature winding.
5. Use a megohmmeter to apply 500 volts DC to either armature lead and the exciter armature frame.
6. A reading of approximately 1.5 MOhms and higher indicates a functional armature.

⚠ Hazardous voltage

⚠ Hot parts

Tools: Ohmmeter, Megohmmeter

1. Stop generator set and disconnect starting battery, negative (--) lead first.
2. Disconnect FP/FN connector between controller/activator board and exciter field.
3. Measure resistance across exciter field FN and FP leads with an ohmmeter.
4. A low reading indicates an internal short; a high reading indicates an open winding.
5. Use a megohmmeter to apply 500 volts DC from FN or FP lead to exciter field frame.
6. A reading of approximately 1.5 MOhms and higher indicates a functional field.

⚠ Hazardous voltage

⚠ Hot parts

Tools: Ohmmeter, Megohmmeter

1. Disassemble generator and disconnect main field (rotor) windings at rectifier module terminals F+ and F--.
2. Measure main field (rotor) resistance across F+ and F-- leads with ohmmeter.
3. A low reading indicates an internal short; a high reading indicates an open winding.
4. Use megohmmeter to apply 500 volts DC to either field lead and main field frame.
5. A reading of 1.5 MOhms and higher indicates the main field is functional.

⚠ Hazardous voltage

⚠ Hot parts

Tools: Multimeter with diode check, Ohmmeter

1. Disconnect exciter armature and main field leads from rectifier module.
2. Perform a diode check on all six rectifier board diodes.
3. Use multimeter diode check or ohmmeter on R x 100 scale.
4. Ohmmeter should show low resistance in one direction and high resistance with leads reversed.
5. Replace rectifier module if any diode tests differently than described.

⚠ Accidental starting

⚠ Hazardous voltage

Tools: Ohmmeter, DC ammeter (0--10 A), 10-amp fuse, 12-volt battery, Voltmeter

1. Stop the generator set and disconnect the FP/FN connector.
2. Measure exciter field winding resistance with an ohmmeter and record the reading.
3. Connect a DC ammeter, 10-amp fuse, and 12-volt battery to FP and FN exciter leads.
4. Start the generator set and note the ammeter reading.
5. An increasing reading indicates a shorted exciter field; a decreasing or unstable reading suggests a running open.
6. If stable, check AC output across stator main windings and compare with Section 1 specifications.
7. Stop the generator set.

⚠ Hazardous voltage

⚠ Hot parts

Tools: Ohmmeter, Megohmmeter

1. Press OFF on generator set controller.
2. Disconnect generator set engine starting battery, negative (--) lead first.
3. Check generator output lead connections and note voltage connection for reassembly.
4. Disconnect all stator leads to isolate windings.
5. Set ohmmeter to R x 1 and check stator continuity using single- or three-phase figures.
6. Check cold resistance of stator windings and compare with Section 1 values.
7. Use megohmmeter to apply 500 volts DC to any stator lead from each winding and stator frame.
8. A reading of 1.5 MOhms and higher indicates the stator is functional.

⚠ Accidental starting

⚠ Hazardous voltage

⚠ Hot parts

Tools: Hoist rated 500 kg or greater, Sling, Two-jaw puller, Soft-jaw vise, Permanent marker or scribe

1. Remove junction box and/or control box panels to access internal components.
2. Disconnect and mark all controller-to-engine and engine-to-alternator harnesses and wiring.
3. Remove power panel as a unit if equipped; remove remaining junction box and/or control box components.
4. Remove nuts and alternator (rodent) guard from studs.
5. Remove exciter field, rectifier module, and exciter armature; disconnect rotor leads from rectifier module.
6. Attach hoist hook to engine lifting eye and remove vibromount locknut, washers, and bolt from each vibromount.
7. Raise alternator end, place wood block under backplate, and lower until supported.
8. Remove four long studs and nuts from end bracket.
9. Mark alignment on stator and engine adapter.
10. Install sling on stator housing and use two-jaw puller to pull end bracket/stator from rotor bearing.
11. Remove stator assembly from rotor; remove or rotate fan guard if necessary.
12. Mark fan position on rotor/drive disc assembly.
13. Remove eight screws and washers and remove alternator fan.
14. Remove eight bolts and remove drive disc/rotor assembly from engine flywheel.
15. Clamp rotor in soft-jaw vise and remove eight bolts to remove drive disc assembly from rotor.

⚠ Accidental starting

⚠ Hazardous voltage

Tools: Suitable hand tools

1. Remove generator set from service: press OFF/RESET or move master switch OFF.
2. Disconnect power to battery charger, if equipped.
3. Disconnect engine starting battery, negative (--) lead first.
4. Open enclosure panels as needed; remove junction box rear cover and alternator rodent guard, if used.
5. Remove five stainless steel nylock nuts securing rotating rectifier board to spacer studs.
6. Remove rotating rectifier board to access alternator leads.
7. Remove five stainless steel hex nuts securing leads A, B, C, F1, and F2 to spacer studs; note positions.
8. Remove three screws securing spacer to exciter armature; remove spacer.

⚠ Accidental starting

⚠ Hazardous voltage

⚠ Hot parts

Tools: Torque wrench, Sling, Hoist, Soft-jaw vise

1. Clean threaded holes and hardware; clamp rotor in soft-jaw vise.
2. Apply thread sealant; install drive disc(s) on rotor and torque eight bolts.
3. Place rotor/drive disc assembly on engine flywheel and torque eight washers and bolts.
4. Align fan using marks; install fan with eight screws and washers, flange away from flywheel; torque.
5. Apply multi-purpose grease to O-ring and install in end bracket bearing bore.
6. Support stator with sling and install over rotor; match alignment marks.
7. Install four long studs through stator into engine adapter.
8. Position end bracket over rotor bearing and install nuts on studs; torque.
9. Raise alternator end, remove wood block, lower set, install vibromount hardware, remove hoist.
10. Apply antiseize compound to keyed end of rotor shaft.
11. Install exciter armature with rotor leads F1/F2 through openings; use new washer; torque retaining bolt.
12. Connect rotor leads F1/F2 to rectifier module positive/negative terminals; torque.
13. For new exciter armature, cut leads to eliminate slack and attach crimp-on terminals; install A/B/C leads; torque.
14. Install rectifier module with spacers and exciter field; torque; secure wires and rodent guard.
15. Reinstall junction/control box and power panel components; reconnect wiring and battery negative last.

⚠ Accidental starting

⚠ Hazardous voltage

Tools: Suitable hand tools, Torque wrench

1. Position rotor leads F1 and F2 around inner diameter of spacer.
2. Route exciter armature leads A, B, and C around outer diameter of spacer.
3. Mount spacer to exciter armature using three screws and torque to 3.9 Nm (35 in. lbs.).
4. Connect leads A, B, C, F1, and F2 to spacer studs using five stainless steel hex nuts; torque to 1.3 Nm (12 in. lbs.).
5. Secure new rotating rectifier board to spacer studs using five stainless steel nylock nuts; torque to 1.3 Nm (12 in. lbs.).
6. Install alternator rodent guard to end bracket, if equipped.
7. Replace junction box panels and enclosure panels, if equipped.
8. Restore service: verify OFF, reconnect battery negative last, reconnect battery charger if equipped.