TM 9-4940-568-20
2-66
Table 2-7. Engine Troubleshooting (CONT).
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
20. COOLANT TEMPERATURE BELOW NORMAL (165 F – 195 F).
Thermostat inoperable, damaged, contaminated or not sealing.
Check/replace thermostat (Para 8-33).
Temperature sending unit or gage malfunctioning.
Replace temperature sending unit (Para 8-34) or gage (Para 8-44).
Coolant not flowing by temperature sending unit.
Flush the system and fill with clean coolant.
21. LUBRICATING OIL PRESSURE LOW.
Lubricating oil level low.
Check for a severe external oil leak that could reduce the pressure.
Coolant temperature high above 203F (98C).
Refer to Troubleshooting Malfunction 18 for Coolant Temperature Above Normal.
Low oil pressure sensor or gage malfunctioning.
Verify the pressure sensor is functioning correctly. Restart generator and verify oil
pressure on gage is less than 14 psi when unit shuts down. If oil pressure is normal,
replace Low Oil Pressure (LOP) switch (S1) (Para 8-39).
Lubricating oil contaminated.
Perform engine oil service (Para 8-2).
