Service manual

9. Troubleshooting 9-2013
3. Measure generator set load capability with shop load bank (de-rate for altitude and
temperature as necessary).
4. Measure AC frequency while running.
5. Measure AC frequency while changing engine rpm to determine if frequency response
matches engine rpm response.
6. Disconnect the generator set control J1 connector, verify the J1 pins are fully inserted, and
inspect pin condition using the steps below:
• Use the test points of the tester tool #420-0603
• Use a mating pin connector, a pin gauge of the same size (.045") as the mating
control connector pin, or any suitable device that will not damage the inside contact
wipers of the pin socket
• Insert, repair, or replace the pins as necessary.
7. Reconnect the J1 connector and test run the generator set for fault occurrence: repair or
replace pins in the connector as necessary.
8. Check air filter cleanliness; replace the air filter as necessary.
9. Check for blocked or damaged exhaust system: repair or replace exhaust components as
necessary.
10. Propane Models
a. When ambient temperatures are less than 40°F vapor–withdrawal, Propane tanks
should be at least half full to provide proper vaporization rate.
b. Propane having more than 2.5 percent Butane will not vaporize in ambients at less
than 32°F; use HD-5 grade Propane.
c. Run the generator set on shop fuel supply; verify the tank level and fuel line condition.
11. Measure steady DC voltage at fuel solenoid while the generator set is running; repair wiring
as necessary.
12. Verify clear vent hose.
13. Check the generator set fuel lines for damage: replace fuel line as required.
14. Measure the fuel supply and regulator lock off pressures.
15. Check the governor, actuator, linkage, and spring for debris, damage, and looseness:
readjust and repair as necessary.
16. Measure field, quadrature, and main winding resistance: clean the slip rings, replace the
brushes, repair the harness, and the replace rotor or stator as necessary.
17. Measure field, quadrature, and main winding resistance to ground: clean the slip rings,
replace the brushes, repair the harness, and replace the rotor or stator as necessary.
18. Measure field, quadrature, and main winding resistance to each other: clean the slip rings,
replace the brushes, repair the harness, and replace the rotor or stator as necessary.
19. Check brush alignment:
Inspect brush wear on the slip rings and verify brush misalignment is toward the windings.
If misalignment is toward the bearing, the cause is not from this tolerance issue and likely
the result of the end bell not being seated properly during assembly. Inspect for cause and
repair as necessary.
96 A030A239 (Issue 10)