HomeEnginesCummins/Onan D6T

Cummins/Onan D6T Engine

The Cummins/Onan D6T is a 2.5 L naturally aspirated engine. It powers generator sets from Cummins/Onan, including the C12 D6.

Also known as: Cummins D6T

2.5 L
Displacement

Engine specifications

Displacement2.5 L
Aspirationnaturally aspirated

Common problems

15
  • Undervoltage sensor pickup and dropout adjustable from 85-100% and 75-98%
    Fix: Dropout adjustable delay from 0.1-30 sec.
  • Under frequency shutdown 81 u
  • Time delay start and stop (cooldown) configurable for time delay of 0-300 seconds prior to starting after receiving a remote start signal
    Fix: Control provides retransfer time delays including time delay emergency to normal (0-1800 sec), programmed transition delay (0-600 sec), and time delay engine cooldown (0-3600 sec).
  • Time delay of 0-600 seconds prior to shutdown after signal to stop in normal operation modes
    Fix: Default for both time delay periods is 0 seconds.
  • Sensor failure indication
    Fix: Logic is provided on the base control to detect analog sensor or interconnecting wiring failures.
  • Overvoltage sensor dropout adjustable from 105-135% of nominal
    Fix: Dropout adjustable delay from 0.5-120 sec.
  • Over/under frequency sensor underfrequency sensing pickup and dropout adjustable from 85-100% and 70-85%
    Fix: Dropout adjustable delay from 0.1-15 sec.
  • Over/under frequency sensor overfrequency sensing dropout adjustable from 105-115% of nominal
    Fix: Dropout adjustable delay from 0.1-15 sec.
  • Over frequency shutdown/warning 81 o
  • Low lube oil pressure warning/shutdown
    Fix: Level is pre-set to match the capabilities of the engine used. Control includes time delays to prevent nuisance shutdown signals.
  • Low coolant temperature warning
    Fix: Indicates that engine temperature may not be high enough for 1 min. and start or proper load acceptance.
  • Low AC voltage shutdown 27
  • High Current warning/shutdown 51
  • High coolant temperature warning/shutdown
    Fix: Level is pre-set to match the capabilities of the engine used. Control includes time delays to prevent nuisance shutdown signals.
  • High AC voltage shutdown 59

Compiled from service & troubleshooting documentation across every generator set that uses the Cummins/Onan D6T.

Common questions

What is the displacement of the Cummins/Onan D6T?

The Cummins/Onan D6T has a displacement of 2.5 liters.

Which generators use the Cummins/Onan D6T engine?

The Cummins/Onan D6T powers 1 generator set(s), including Cummins/Onan C12 D6.

What is a common problem with the Cummins/Onan D6T engine?

A commonly reported issue on generators using the Cummins/Onan D6T is: Undervoltage sensor pickup and dropout adjustable from 85-100% and 75-98%. Fix: Dropout adjustable delay from 0.1-30 sec..