HomeEnginesCummins/Onan KTTA50-G2

Cummins/Onan KTTA50-G2 Engine Engine

The Cummins/Onan KTTA50-G2 is a 50.3 L 16-cylinder turbocharged and aftercooled engine rated at 1800 rpm, producing up to 1656.1 kW. It powers generator sets from Cummins/Onan, including the DFM. It holds 151.4 L (40.0 gal) of oil.

Also known as: Cummins KTTA50-G2

Part of the Cummins/Onan KTTA50 engine family — 2 variants share parts & fitment.

50.3 L
Displacement
16
Cylinders
1800 rpm
Rated speed
1656 kW
Gross power

Engine specifications

Oil capacity151.4 L
Displacement50.3 L
Cylinders16
Aspirationturbocharged and aftercooled
Rated speed1800 rpm
Gross power1656 kW

Generator sets powered by this engine

1

This engine also powers 375 machine(s) on Power Equipment Info.

Common problems

15
  • Warning Status Indicator: This yellow lamp is lit whenever the control detects a warning condition.
    Fix: After the condition is corrected, warning indicators can be reset by pressing the Reset switch. (It is not necessary to stop the generator set.) In auto mode, warning indicators can also be reset by cycling the remote reset input after the condition is corrected.
  • Warning lamp lights. 210
    Fix: Indicates set is in standby mode but is not operating. Warning occurs when engine coolant temperature is 70 F (21 C) or lower. NOTE: In applications where the ambient temperature falls below 40F (4C), Low Engine Temp may be indicated even though the coolant heaters are operating. Indicates engine coolant heater is not operating or is not circulating coolant. Check for the following conditions: a. Coolant heater not connected to power supply. Check for blown fuse or disconnected heater cord and correct as required. b. Check for low coolant level and replenish if required. Look for possible coolant leakage points and repair as required. c. Contact an authorized service center if none of the above.
  • The FAULT 1 or FAULT 2 fault lamp lights. Engine shuts down immediately, or engine continues to run. FAULT 1 or FAULT 2
    Fix: A. Fault lamp on. Correct fault and reset control. b. Poor battery cable connections. Clean the battery cable terminals and tighten all connections. c. Discharged or defective battery. Recharge or replace the battery.
  • Shutdown Status Indicator: This red lamp is lit whenever the control detects a shutdown condition.
    Fix: After the condition is corrected, shutdown indicators can be reset by turning
  • Shutdown lamp lights. 200
    Fix: Indicates engine oil pressure has dropped to an unacceptable level. If generator is powering critical loads and cannot be shut down, wait until next shutdown period then follow 201 Low Oil Pressure procedure. If engine can be stopped, follow 201 procedure. To check oil pressure, access Oil Pressure menu prior to clearing the fault.
  • PCC memory error. Data corruption of noncritical operating parameters. Warning lamp lights. 251
    Fix: Contact an authorized service center.
  • PCC memory error. Data corruption of critical operating parameters. Shutdown lamp lights. 250
    Fix: Contact an authorized service center.
  • OVERCRANK lamp lights and engine cannot be started
    Fix: A. Check for empty fuel tank, fuel leaks, or plugged fuel lines and correct as required. d. Refer to Step 5.
  • Overcrank fault
    Fix: Place Run/Stop/Remote switch in STOP position, depress Reset switch momentarily, wait two minutes for starter motor to cool and repeat starting procedure
  • One or more of the phase voltages has exceeded 130% of nominal, or has exceeded 110% of nominal for 10 seconds. Shutdown lamp lights. 301
    Fix: Contact an authorized service center.
  • Non-Automatic lamp flashes.
    Fix: Indicates Run/Off/Auto switch is not in the Auto position. This will prevent automatic starting if an automatic transfer switch is used. Move the Run/Off/Auto switch to the Auto position for automatic operation.
  • Indicates engine coolant level has fallen below the trip point. Shutdown lamp lights. 220
    Fix: A. Check coolant level and replenish if low. Look for possible coolant leakage points and repair if necessary. b. Reset control and restart after locating and correcting problem. Contact an authorized service center.
  • Green RUN lamp lights following engine loads and cannot be shut down
    Fix: A. Reduce load if possible by turning off non-critical loads. b. Check air inlets and outlets and remove any obstructions to airflow. c. Open doors or windows in generator area to increase ventilation. Allow engine to cool down completely before proceeding with the following checks: a. Check coolant level and replenish if low. Look for possible coolant leakage points and repair b. Check for obstructions to cooling airflow and correct as necessary. c. Check for a slipping fan belt and tighten if required. d. Reset control and restart after locating and correcting problem. Contact your Dealer or Distributor if none of the above.
  • Fuel supply is running low. Warning lamp lights. 241
    Fix: Check fuel supply and replenish as required.
  • Engine will not crank. Shutdown lamp lights. 221
    Fix: A. Poor battery cable connections. Clean the battery cable terminals and tighten all connections. b. Discharged or defective battery. Recharge or replace the battery. c. Contact an authorized service center for service of starter and starting system.

Compiled from service & troubleshooting documentation across every generator set that uses the Cummins/Onan KTTA50-G2.

Maintenance schedule

ItemSpecCapacityPart #Interval
Air filterMaximum Air Cleaner Restriction, 25.0 in. H2O (6.2 kPa) find
Fuel filter find
Oil filterFive spin-on, full flow find
Belt find
Coolant386.1 L
OilCummins151.4 L

Pooled from every document that names this exact engine — confirm the interval and part number against your unit's serial number.

Parts cataloged across the Cummins/Onan KTTA50 family

31
Part #DescriptionCategory
140-2501Cleaner, Air (Disposable)air_filter
140-2502Band, Mounting – Air Cleanerair_filter
0300-4623-54DFLC BR (0-480V)current_transformer
503-1484Elbow, Hose (45 Deg) (7" ID)hose
503-1620Hose – Bulk (3/8" ID) (Order by the Foot)hose
503-1870-11Clamp, Hosehose
503-1870-12Clamp, Hosehose
140-1260Fitting, Safety Filterother_service
140-1548Indicator, Serviceother_service
140-2508Tube, Air Inlet (7" x 9" - 3/4")other_service
140-2528Shield – Air In Heatother_service
332-2634Clamp, Retainer 4 Prior To December 1996 Production (Mounted On Top And Side Of Control Box Wrapper)other_service
503-1717Elbow, Reducer (45 Deg) (7" ID to 6" ID)other_service
503-1720Insert, Reducer (6" OD to 5-1/2" ID)other_service
518-0548-24Clamp, Retainer Begin December 1996 Production (Mounted On Top And Side Of Control Box Wrapper On The Side Towards The Control Box Cover)other_service
518-0548-42Clamp, Retainer 4 Prior To December 1996 Production (Mounted On Top And Side Of Control Box Wrapper)other_service
526-0030Washer, Flat (3/8")other_service
800-0055Screw, Cap – Hex Head (3/8–16 x 2-1/4")other_service
800-0094Screw, Cap – Hex Head (1/2–13 x 2")other_service
821-0029Screw, Self–Locking – Hex Washer Head (3/8–16 x 3/4")other_service
821-0033Screw, Self–Locking – Hex Washer Head (7/16–14 x 3/4")other_service
821-5004-03Screw, Self-Locking – Hex Washer Head (3/8–16 x 1")other_service
870-0281Nut, Self-Locking – Hex Washer Head (3/8–16)other_service
900-0181PCC Control Service Manualother_service
960-0602other_service
960-0606other_service
960-0608other_service
960-0181service_manual
960-0302service_manual
960-0504PCC Control Service Manualservice_manual
960-0507Detector Control Service Manualservice_manual

Parts cataloged across all variants of this engine family — verify the exact part fits your specific variant and serial number before ordering.

Common questions

What is the oil capacity of the Cummins/Onan KTTA50-G2?

The Cummins/Onan KTTA50-G2 engine has an oil capacity of 151.4 liters.

What is the displacement of the Cummins/Onan KTTA50-G2?

The Cummins/Onan KTTA50-G2 has a displacement of 50.3 liters with 16 cylinders.

Which generators use the Cummins/Onan KTTA50-G2 engine?

The Cummins/Onan KTTA50-G2 powers 1 generator set(s), including Cummins/Onan DFM.

What is a common problem with the Cummins/Onan KTTA50-G2 engine?

A commonly reported issue on generators using the Cummins/Onan KTTA50-G2 is: Warning Status Indicator: This yellow lamp is lit whenever the control detects a warning condition.. Fix: After the condition is corrected, warning indicators can be reset by pressing the Reset switch. (It is not necessary to stop the generator set.) In auto mode, warning indicators can also be reset by cycling the remote reset input after the condition is corrected..