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Cummins/Onan KTA50 / KTTA50 Engine

Name: Cummins/Onan KTA50 / KTTA50 Engine
Brand: Cummins/Onan

The Cummins/Onan KTA50 / KTTA50 is a turbocharged engine. It powers generator sets from Cummins/Onan, including the DFM. It holds 169 L (44.6 gal) of oil and 348 L (91.9 gal) of coolant.

Also known as: Cummins KTA50 / KTTA50

Part of the Cummins/Onan KTA50 engine family — 13 variants share parts & fitment.

169.0 L

Oil capacity

On this pageSpecs Generator sets Maintenance FAQ Service intervals Torque & specs Fluids Fault codes Procedures Wiring

Engine specifications

Oil capacity	169.0 L
Coolant capacity	348.0 L
Aspiration	Turbocharged

Generator sets powered by this engine

Cummins/Onan DFM

How to read your Cummins/Onan engine serial & model number →

Common problems

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 KTA50 / KTTA50.

Maintenance schedule

Item	Spec	Capacity	Part #	Interval
Air filter	Clean with low pressure compressed air 30 psi/207 kPa, or soak 15 min in Donaldsons D1400 solvent		—
Fuel filter			—
Oil filter			—
Battery	Four, 12 Volt; Group 8D; CCA 1400 minimum; check electrolyte level at least every 200 hours		—	200 hr
Belt	Spring-loaded idler maintains correct belt tension		—
Coolant	Drain and replace mixture every year or after 500 hours	348.0 L	—	500 hr
Coolant filter			—
Oil	Refer to Cummins engine Operation and Maintenance Manual	169.0 L	—	250 hr

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

Service intervals

Item	Action	Hours	Months	Notes
crankcase oil	Change	50 hr		First service — Drain and replace the crankcase oil after the first 50 hours of operation on new generator sets
Crankcase oil and filter	Change	250 hr	12 mo	Standby applications: change oil every 12 months or 250 hours, whichever comes first
Generator bearing (P7 only)	Lubricate	4500 hr		Re-lubrication period 4000-4500 hours; 75 grams Kluber ASONIC GHY72

Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.

Service specifications

Type	Item	Value	Unit	Condition
Clearance	Air cleaner nozzle distance from element	1	inch (25 mm) minimum	when cleaning with compressed air
Clearance	Float switch assembly float lift clearance below C-clip stop	1/8	inch (3 mm)	use a feeler gauge
Clearance	Generator-to-engine angular alignment (T.I.R.)	.001 in. per inch of radius (center of shaft to indicator axis), maximum	in	750 kW gensets and larger
Other	AVR Droop setting	5	% at full load, 0 PF
Other	AVR voltage regulation (load regulation)	approximately ±0.5	% RMS
Other	Battery specific gravity (high ambient, above 95F/35C)	1.225		recommended to reduce electrolyte loss
Other	Battery specific gravity (recharge threshold)	below 1.260
Other	Continuous crank without cycle cranking option (PCC)	up to 75	seconds
Other	GOV GAIN default value for paralleling applications	70	%
Other	Output frequency adjustment range	+/- 5	%	set running, not in idle mode
Other	Over/Under Frequency Sensor Module - Over Hz Set, 50 Hz nominal	55	Hz	reset 53 Hz
Other	Over/Under Frequency Sensor Module - Over Hz Set, 60 Hz nominal	65	Hz	reset 63 Hz
Other	Over/Under Frequency Sensor Module - Under Hz Set, 50 Hz nominal	45	Hz	reset 47 Hz
Other	Over/Under Frequency Sensor Module - Under Hz Set, 60 Hz nominal	55	Hz	reset 57 Hz
Other	Over/Under Voltage Sensor Module time delay	typically 25 percent, approximately 2.5	seconds
Other	Overcrank cranking limit	75	seconds	three 15-second cranking cycles with two 15-second rest periods
Other	Overcrank cycle cranking (Detector, standard)	three 15-second cranking cycles with two 15-second rest periods	seconds
Other	Overcrank cycle cranking (PCC)	3, 4, or 5 cycles; crank and rest times 7 to 20	seconds
Other	Overcrank limit (Detector, optional)	75	seconds
Other	REG VHZ (underfrequency roll-off) adjustable range	1 through 50; normal range 7 through 21
Other	Start delay (PCC, remote start in Auto)	0 to 300	seconds
Other	Start delay adjustment range	0 to 300	seconds
Other	Stop delay (PCC, remote stop in Auto)	0 to 600	seconds
Other	Stop delay adjustment range	0 to 600	seconds
Other	Under Frequency Roll Off (UFRO) knee point, 50 Hz units	48 to 49	Hz
Other	Under Frequency Roll Off (UFRO) knee point, 60 Hz units	58 to 59	Hz
Pressure	Air cleaner cleaning compressed air pressure	30	psi (207 kPa)	blow through element from clean side
Pressure	Air cleaner element cleaning, compressed air pressure	30	psi (207 kPa)	blow through element from clean side; nozzle at least 1 inch (25 mm) away
Pressure	Detector oil pressure normal range after reset	25 to 40	psi (172 to 275 kPa)
Pressure	Engine oil pressure - K19 normal	50-70	psi (345-482 kPa)	run mode
Pressure	Engine oil pressure - K38 normal	45-65	psi (310-448 kPa)	run mode
Pressure	Engine oil pressure - K50 normal	50-70	psi (345-482 kPa)	run mode
Pressure	Engine oil pressure - L10/M11 normal	30-50	psi (207-345 kPa)	run mode
Pressure	Engine oil pressure - NTA 855 normal	35-50	psi (241-345 kPa)	run mode
Pressure	Engine oil pressure - V28 normal	50-90	psi (345-620 kPa)	run mode
Pressure	Engine oil pressure shutdown limit - L10/M11	20	psi (138 kPa)	run mode value
Pressure	Engine oil pressure shutdown limit - L10/M11	8	psi (55 kPa)	idle mode value
Pressure	Engine oil pressure warning limit - L10/M11	12	psi (83 kPa)	idle mode value
Pressure	Engine oil pressure warning limit - L10/M11	25	psi (172 kPa)	run mode value
Pressure	Idle oil pressure (PCC)	20	psi (138 kPa)	idle
Pressure	Idle oil pressure shutdown limit (PCC)	10	psi (69 kPa)	idle
Pressure	Idle oil pressure warning limit (PCC)	15	psi (103 kPa)	idle
Pressure	K19 engine idle oil pressure	20	psi (138 kPa)	idle
Pressure	K19 engine normal oil pressure	50-70	psi (345-482 kPa)	normal run
Pressure	K19 oil pressure shutdown/warning limits	shutdown 35 psi (241 kPa) run; warning 40 psi (276 kPa) run; shutdown 10 psi (69 kPa) idle; warning 15 psi (103 kPa) idle	psi (kPa)
Pressure	K38 engine idle oil pressure	20	psi (138 kPa)	idle
Pressure	K38 engine normal oil pressure	45-65	psi (310-448 kPa)	normal run
Pressure	K38 oil pressure shutdown/warning limits	shutdown 35 psi (241 kPa) run; warning 40 psi (276 kPa) run; shutdown 10 psi (69 kPa) idle; warning 15 psi (103 kPa) idle	psi (kPa)
Pressure	K50 engine idle oil pressure	20	psi (138 kPa)	idle
Pressure	K50 engine normal oil pressure	50-70	psi (345-482 kPa)	normal run
Pressure	K50 oil pressure shutdown/warning limits	shutdown 35 psi (241 kPa) run; warning 40 psi (276 kPa) run; shutdown 10 psi (69 kPa) idle; warning 15 psi (103 kPa) idle	psi (kPa)
Pressure	L10/M11 engine idle oil pressure	15	psi (103 kPa)	idle
Pressure	L10/M11 engine normal oil pressure	30-50	psi (207-345 kPa)	normal run
Pressure	L10/M11 oil pressure shutdown limit	20	psi (138 kPa)	run mode value
Pressure	L10/M11 oil pressure shutdown limit	8	psi (55 kPa)	idle mode value
Pressure	L10/M11 oil pressure warning limit	12	psi (83 kPa)	idle mode value
Pressure	L10/M11 oil pressure warning limit	25	psi (172 kPa)	run mode value
Pressure	Low oil pressure shutdown	14	psi (97 kPa)	oil pressure drops below; time-delayed about 10 seconds following starter disconnect, inhibited during cranking
Pressure	Low oil pressure shutdown	below 14	psi (97 kPa)	time delayed ~10 seconds following starter disconnect
Pressure	Low oil pressure shutdown (Detector)	14	psi (97 kPa)	shutdown trip, time-delayed about 10 seconds after starter disconnect

Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.

Recommended fluids

Fluid	Grade	Standard	Ambient	Capacity	Notes
Coolant	Water/antifreeze mixture (permanent type antifreeze)				Water should be clean, low in mineral content, free of chloride, sulphate or acid; mix per supplier for lowest expected ambient temperature; do not use antifreeze containing anti-leak additives
Coolant	soft water / E.G. / DCA mixture				Cooling system to be filled with soft water/E.G./DCA mixture (on-site review checklist).
Engine oil		API Class CC/CD, maximum sulphated ash content 1.85 percent			Multigrade/multiviscosity oils recommended; single grade oil not recommended; do not mix oils of different classification or brand
Engine oil	SAE 5W synthetic	API class CC/CD; sulphated ash not to exceed 1.85 percent	below -25°C		For ambient temperature consistently below -30 deg F (-25 deg C) with no provision to keep engine warm; pour point 9 deg F (5 deg C) below lowest expected temperature; viscosity max 10,000 mPa.s at -31 deg F (-35 deg C) and min 4.1 mm2/s at 212 deg F (100 deg C); do not use petroleum base 5W grade oil
Fuel	Diesel				Day tank fuel transfer pump maintains reservoir of diesel fuel in the day tank.
Fuel	No. 2 diesel				Engine will also operate on No. 1 fuel or similar fuels if they meet specifications; consult engine manufacturer for non-standard fuel
Grease	Kluber, type ASONIC GHY72			75.0 grams	P7 generator bearing re-lubrication grease fill quantity; fill period 4000-4500 hours. Must not be mixed with any other type.
Grease	Lithium based grease, Mobilux No. 2 or Shell Alvania R3		-30°C to 120°C	2.74 oz (81 ml)	End bearing lubricant; grease equally divided between bearing, bearing cap cavity and bearing cartridge cavity.
Other	Donaldsons D1400 solvent (or equivalent)				Air cleaner element cleaning: soak filter at least 15 minutes in water and Donaldsons D1400 solvent.

Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.

Fault codes

Code	Name	Meaning	Severity	Action
101	IDLE MODE	Indicates that the engine is operating in idle mode. Grounding the engine idle input causes generator build-up to be inhibited and the engine to be governed at 800 RPM.	Warning	Remove ground from engine idle input to return to normal speed and voltage.
102	EMERGENCY STOP	Local or remote Emergency Stop activated	Shutdown	Turn the switch clockwise and allow it to pop out (local only). Move the Run/Off/Auto switch to Off. Press the Reset switch. Select Run or Auto, as required.
200	LOW OIL PRESSURE	Indicates engine oil pressure has dropped to an unacceptable level.	Warning	If generator is powering critical loads and cannot be shut down, wait until next shutdown period and then follow 201-SHUTDOWN procedure. Access the Oil Pressure menu prior to clearing the fault.
201	LOW OIL PRESSURE	Indicates engine oil pressure has dropped below the shutdown trip point.	Shutdown	Check oil level, replenish if low, reset control and restart; contact authorized service center.
204	OIL PRES SENDER	Indicates that the control has sensed that the engine oil pressure sender is out of its working range.	Warning	Check that the engine oil pressure sender is properly connected.
210	LOW COOLANT TEMP	Warning occurs when engine coolant temperature is 70°F (21°C) or lower.	Warning	Indicates engine coolant heater is not operating or is not circulating coolant. Check coolant heater power supply, low coolant level, and heater element current draw.
211	HIGH COOLANT TEMP	Indicates the engine coolant temperature is getting close to the recommended maximum temperature limit: 215° F (102° C) − standby or 207° F (97° C) − primary.	Warning	Review 212 correction list; increase in load or higher ambient may cause shutdown.
212	HIGH COOLANT TEMP	Indicates engine has overheated (coolant temperature above 215° F (102° C) − standby or 207° F (97° C) − primary).	Shutdown	Cool engine; check coolant level, airflow obstructions and fan belt; reset and restart.
213	COOLANT SENDER	Resistance of the coolant temperature sender is out of range.	Warning	Contact authorized service center.
214	LOW COOLANT LVL	Indicates engine coolant level has fallen below the trip point.	Warning	Cool engine; check coolant level and leaks; reset control and restart.
215	LOW COOLANT LVL	Indicates engine coolant level has fallen below the trip point.	Shutdown	Cool engine; check coolant level and leaks; reset control and restart. Shutdown will not occur in Idle mode.
220	MAG PICKUP	Mag pickup speed indication not sensed or does not match output frequency	Shutdown	Restart and check RPM; check PCC model setting; inspect and test MPU.
221	FAIL TO CRANK	Possible fault with control or starting system.	Shutdown	Clean and tighten battery cables; recharge or replace battery; contact service center.
222	OVERCRANK	Possible fuel system problem.	Shutdown	Check fuel tank, leaks, plugged lines, fuel filter and air filter; reset control and restart.
223	OVERSPEED	Indicates engine has exceeded normal operating speed. (115% ±1% of nominal).	Shutdown	Contact authorized service center.
224	FAIL TO SYNCHRONIZE	Generator set has not synchronized to the system bus within the allowable time frame.	Warning	Check governor system stability; adjust governing and synchronizer parameters; check fuel system.
226	FAIL TO CLOSE	Paralleling breaker has been given a signal to close, but has not closed properly.	Shutdown	Verify breaker charging mechanism; check close signal; verify auxiliary contact signals.
230	LOW DC VOLTAGE	Indicates battery voltage is below 10 VDC.	Warning	Recharge or replace the battery; check the battery charger fuse. Clean and tighten battery cable connections. Check engine DC alternator; replace if normal charging voltage is not obtained. Check float level if applicable.
231	HIGH DC VOLTAGE	Indicates battery voltage exceeds 32 VDC.	Warning	Lower battery charger float level if applicable; check engine DC alternator.
232	WEAK BATTERY	Indicates battery voltage drops below 60% of nominal for two seconds, during starting.	Warning	See warning message 230 LOW DC VOLTAGE.
240	LOW FUEL−DAY	Indicates day tank fuel supply is running low.	Warning	Check fuel supply and replenish as required.
241	LOW FUEL	Low fuel signal received.	Warning	Check fuel supply and replenish; check for short to ground in external wiring.
250	EEPROM ERROR	PCC memory error; data corruption of critical operating parameters.	Shutdown	Perform initial start setup procedure; replace digital board (A32) if fault repeats.
251	EEPROM ERROR	PCC memory error; data corruption of noncritical operating parameters.	Warning	Perform adjustment and calibration procedures; replace digital board (A32) if fault repeats.
252	EEPROM ERROR	PCC memory error; data corruption of noncritical operating parameters.	Warning	Verify selected values; repeat save operation; replace digital board (A32) if fault repeats.
260	CUSTOMER FAULT 1	When a customer defined input is closed to ground, the corresponding fault message is displayed. Default message; editable for customer site requirements.	Warning	Shutdown or warning preselected; message is editable; contact authorized service center.
261	GROUND FAULT	When a customer defined input is closed to ground, the corresponding fault message is displayed. Default message; editable for customer site requirements.	Warning	Shutdown or warning preselected; message is editable; contact authorized service center.
262	RUPTURE BASIN	When a customer defined input is closed to ground, the corresponding fault message is displayed. Default message; editable for customer site requirements.	Warning	Shutdown or warning preselected; message is editable; contact authorized service center.
263	HIGH GEN TEMP	When a customer defined input is closed to ground, the corresponding fault message is displayed. Default message; editable for customer site requirements.	Warning	Shutdown or warning preselected; message is editable; contact authorized service center.
270	PHASE ROTATION	The phase relationship between the generator set and the system bus is not matched.	Shutdown	Verify genset phase rotation matches bus; verify control wiring to bus PT module.
272	FIRST START	PowerCommand control is not receiving a proper signal from the system master first start sensor.	Warning	Verify Master First Start Sensor and interconnection wiring.
301	HIGH AC VOLTAGE	One or more phase voltages exceeded 130% of nominal, or exceeded 110% of nominal for 10 seconds.	Shutdown	Contact authorized service center.
303	LOW AC VOLTAGE	One or more phase voltages dropped below 85% of nominal for 10 seconds.	Shutdown	Contact authorized service center.
313	UNDER FREQUENCY	Indicates that engine speed has dropped below 90% of nominal for 10 seconds. Five seconds before shutdown, a Load Dump signal is initiated.	Shutdown	Load Dump signal initiated five seconds before shutdown; contact authorized service center.
320	OVERCURRENT	Indicates that generator output current has exceeded 110% of rated for 60 seconds.	Warning	Contact authorized service center.
321	OVERCURRENT	Indicates that generator output current has exceeded 110% of rated, and that a PCC time/current calculation has initiated an overcurrent shutdown.	Shutdown	Contact authorized service center.
322	SHORT CIRCUIT	Indicates that generator output current has exceeded 175% of rated.	Shutdown	Contact authorized service center.
330	OVERLOAD	Three-phase power output exceeds 105% of standby (or 115% of prime) rating.	Warning	Load Dump output activated after five seconds; warning activated after 60 seconds; contact authorized service center.
335	REVERSE POWER	Power is flowing into the generator set rather than out from the unit.	Shutdown	Verify CT connections, load sharing lines, and generator set frequency/voltage.
337	LOSS OF EXCITATION	Alternator excitation system is improperly adjusted or has failed.	Shutdown	Check output voltage calibration, load sharing lines, and leading power factor loads.
FAULT 1	Fault 1	Undedicated customer-defined fault; may be programmed as timed or non-timed shutdown or fault light only.
FAULT 2	Fault 2	Undedicated customer-defined fault, same features as Fault 1.
HI ENG TEMP	High Engine Temperature	Engine shut down due to critically high coolant temperature (above 215F/102C).	Shutdown
LO FUEL	Low Fuel	Fuel supply is marginally low, if equipped (Detector-12).	Warning
LO OIL PRES	Low Oil Pressure	Engine shut down due to critically low oil pressure (below 14 psi/97 kPa).	Shutdown
LOW ENG TEMP	Low Engine Temperature	Engine water jacket temperature is 70F/21C or lower; indicates possible inoperative coolant heater (Detector-12).	Warning
OVERCRANK	Overcrank	Starter locked out because of excessive cranking time (limited to 75 seconds).	Shutdown
OVERSPEED	Overspeed	Engine shut down because of excessive speed.	Shutdown
PRE HI ENG TEMP	Pre-High Engine Temperature	Coolant temperature is marginally high (205F/97C or higher).	Warning	Attend to when generator set is shut down.
PRE LO OIL PRES	Pre-Low Oil Pressure	Engine oil pressure is marginally low (20 psi/138 kPa or less).	Warning	Attend to when generator set is shut down.
RUN	Run	Green lamp comes on when both primary and secondary starter circuits open after unit starts.	Info
SWITCH OFF	Switch Off	Generator set is not in automatic start operation mode (flashing red).	Info

Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.

Procedures

Aligning Generator with Engine (Angular Alignment) adjustment

⚠ Accidental starting of the generator set during this procedure presents the hazard of severe personal injury or death.

Tools: Dial indicator, Shims

Disconnect the negative (-) battery cable(s) before beginning.
Fasten a dial indicator to the generator shaft or cooling fan with the sensing point on the capscrew head or flat surface of the drive disc at the bolt circle diameter.
Bar the engine over in a clockwise rotation as viewed from engine flywheel; do not allow it to roll back on compression.
Determine the total indicator reading (T.I.R.) as the sum of the maximum positive and negative dial indicator readings over one revolution.
Measure the distance from the center of the generator shaft to the indicator measuring point.
Measure the distance from the generator side of the flex discs to the center of the generator mounting bolt.
Compare the distances; multiply this ratio times one half the T.I.R. to approximate the amount of shims to remove or add.

Angular Alignment Procedure (Generator to Engine) adjustment

⚠ Accidental starting during this procedure presents the hazard of severe personal injury or death.

⚠ Do not bar engine over by prying on fan blade.

Tools: dial indicator

Disconnect the negative (-) battery cable(s) before beginning.
Fasten a dial indicator to the generator shaft or cooling fan with sensing point resting on the drive disc capscrew head/flat surface at the bolt circle diameter.
Bar the engine over in a clockwise rotation as viewed from the engine flywheel; do not allow it to roll back on compression at the end of travel of each reading.
Record the total indicator reading (T.I.R.) as the sum of the maximum positive and negative dial indicator readings over one engine revolution.
Compare the measured T.I.R. to the maximum allowed (.001 in. per inch of radius from center of shaft to indicator axis); add or remove shims under the generator mounting feet to correct.

Axial Alignment Procedure (Generator to Engine) adjustment

Tools: dial indicator

Fasten a dial indicator holding device to the skid base, engine block, or generator shell with the sensor point resting on the generator shaft hub.
Bar the engine over in a clockwise rotation through a couple of rotations, recording indicator readings at eight equally spaced points around the shaft diameter to obtain axial T.I.R.
Reduce the measured T.I.R. runout by one half if excessive vibration remains after angular alignment.

Electric Governor Preliminary Adjustments adjustment

Idle Speed potentiometer: turn the screw counterclockwise 20 turns, then clockwise 10 turns to set mid position.
Run Speed potentiometer: turn the screw counterclockwise 20 turns, then clockwise 10 turns to set mid position.
Gain potentiometer: turn the screw fully counterclockwise.
Droop potentiometer: turn fully counterclockwise for isochronous operation.
Droop potentiometer: turn to approximately 40 for 3 percent droop, or approximately 80 for 5 percent droop.

Fine Speed Adjustment adjustment

After the gain adjustment is made, adjust full load governed engine speed to equal the desired speed (60 Hz, 1800 RPM or 50 Hz, 1500 RPM).
Use the SPEED ADJUST potentiometer on the engine instrument panel for fine speed adjustments of less than +/-100 RPM.

Gain Adjustment adjustment

Close the main line circuit breaker and apply approximately 1/4 of the rated load.
Make sure the engine speed is constant. If constant, turn the GAIN potentiometer clockwise slowly until the engine speed is not constant.
Slowly turn the potentiometer counterclockwise until a constant speed is achieved.
Turn the potentiometer counterclockwise an additional 1/2 division.

Generator/PCC Control Isolation Procedure diagnostic

⚠ HIGH VOLTAGE. Touching uninsulated high voltage parts inside the control box can result in severe personal injury or death.

Tools: Voltmeter, Jumpers, 12 volt battery

Throw the line circuit breaker OFF and shut down the set.
Remove accessory box cover; remove plug P10 from A37 J10.
Prepare to measure output voltage across generator terminals.
Connect 12V battery jumpers to X (P10-6 red) and XX (P10-3 brown).
Check polarity; incorrect polarity makes the test inconclusive.
Start set and connect battery negative to the XX lead.
Rated or higher balanced voltage means generator circuitry is OK.
Unbalanced voltage: troubleshoot main stator; low voltage: exciter/field.

Insulation Resistance (Megger) & Polarization Index (PI) Testing diagnostic

⚠ The windings of medium-voltage (601 through 15,000 volts) generator sets must be dry before the generator is operated.

Tools: Megger or insulation resistance meter, Grounding cluster, High voltage gloves

Perform the Generator Set Grounding Procedure.
Disconnect plug J10 from A37 and AC control leads 4,5,6,7,8.
If RTD option installed, ground all six RTD temperature leads (18 leads).
Perform Insulation Resistance Test and PI Test for desired windings.
Megger test: apply voltage for up to one minute.
PI test: apply voltage for ten minutes; record 1-minute and 10-minute readings.
PI ratio of 2 or greater is good for new and in-service sets.
Investigate and correct low readings before returning set to service.

Megger and PI Test diagnostic

⚠ Medium-voltage (601 to 15,000 volts) windings must be dry before the generator is operated.

Tools: Megger or Insulation Resistance Meter, Wheatstone bridge or digital ohmmeter, Grounding Cluster

Perform the Generator Set Grounding Procedure.
Disconnect plug J10 from the voltage regulator output module and the AC control leads (marked 4, 5, 6, 7, 8).
If RTD option installed, ground all six RTD temperature leads (18 leads total).
Perform the Winding Resistance Test for the desired windings.
Perform the Insulation Resistance (Megger) Test and PI Test for the desired windings.
Megger test: apply voltage for up to one minute.
PI test: apply voltage for ten minutes; record resistance at one minute and ten minutes.
PI is the ten-minute reading divided by the one-minute reading; ratio of two or greater is good.

Testing Diodes diagnostic

⚠ Layers of dust can cause diodes to overheat and fail. Brush dust off regularly.

Tools: Ohmmeter

Disconnect the diode pigtails from the terminal posts.
Using an ohmmeter, measure resistance between pigtail and mounting plate.
Reverse meter test probes and repeat the tests.
Resistance should be high in one direction and low in the other.
If high or low in both directions, replace the diode.

Testing the Float Switch Assembly diagnostic

Tools: Ohmmeter, Feeler gauge

Remove the fuel pump control cover, disconnect the wiring jack and unscrew the assembly from the top of the day tank.
With an ohmmeter, test for electrical continuity between each pair of colored leads while holding the assembly vertical; all readings should be zero.
Lift each float, in turn, to 1/8 inch (3 mm) below the C-clip stop above it and test for continuity; all readings should be infinity.
Use pipe thread sealant when replacing the assembly.

Testing the PMG diagnostic

⚠ HAZARDOUS VOLTAGE. Touching uninsulated parts inside the control housing and power output boxes can result in severe personal injury or death.

Tools: Digital multimeter, Wheatstone bridge or digital ohmmeter

Disconnect PMG leads PMG 2, PMG 3, PMG 4 from connectors in AC harness.
Start the engine and let speed stabilize.
Measure voltage across lead pairs PMG 2&3, 3&4, 4&2.
Voltage should be at least 150 VAC for 50 Hz sets, 180 VAC for 60 Hz.
Stop set; measure resistance across the lead pairs with a Wheatstone bridge.

Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.

Voltage reconnection

Phase	Connection	Leads	Notes
	12 lead generator sets	Load wires are routed through the CTs	Reconnectable gensets (12 leads) have dual secondary CTs (3 pins); CT wire 2/3 to pin 2 (high voltage) or pin 3 (low voltage).
	6 lead generator sets	Generator output leads are routed through the CTs	Non-reconnectable gensets (6 leads) have single secondary CTs (2 pins).
	Cummins PowerCommand generic AC Reconnect Wiring Diagram 625-2755 (Rev. D) and 625-3100 (Rev. F)		Applies to models DFAA, DFAB, DFAC, DFBF, DFCB, DFCC, DFEB, DFEC, DFFB, DFGA, DFGB, DFJA, DFJB, DFJC, DFJD, DFLB, DFLC, DFLD, DFMB (625-2755) and models DFAA-DFMB plus DFCE, DFED, DQAA, DQAB, DQBA, DQBB (625-3100).
A (U)	CT21	U load leads (A phase)	CT dot must face the generator; CT terminal 1 connects to metering circuit, terminal 2/3 to ground.
B (V)	CT22	V load leads (B phase)	CT dot must face the generator; terminal 1 to metering circuit, terminal 2/3 to ground.
C (W)	CT23	W load leads (C phase)	CT dot must face the generator; terminal 1 to metering circuit, terminal 2/3 to ground.

Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.

Parts cataloged across the Cummins/Onan KTA50 family

298

Part #	Description	Category
140-2096	Element, Primary (Outer)	air_filter
140-2097	Cleaner, Air (Includes Elements)	air_filter
140-2467	Element, Safety (Inner)	air_filter
140-2501	Cleaner, Air (Disposable)	air_filter
140-2502	Band, Mounting	air_filter
140-2503	Bracket, Mounting	air_filter
140-3163	Cleaner, Air (No Replaceable Element)	air_filter
140-3230	Cleaner, Air (Includes Elements - See Ref. No. 25 and 26)	air_filter
309-0272	Regulator, Voltage - 24 VDC (Used on 35 A MP Alternator)	alternator
503-1743-01	Alternator & Orive Components Group Pulley, Alternator - Multi Groove (Use with 35 AMP Alternator)	alternator
206587	CAP, MAIN BEARING	bearing_cap
206588	CAP, MAIN BEARING	bearing_cap
98-5347	Decal - Caution Fan Drive & Lube Components Group Belt.	belt
106069	SCREW, HEXAGON HEAD CAP	bolt
205584	SCREW, TWELVE POINT CAP	bolt
206028	SCREW, SOCKET HEAD CAP	bolt
3032633	SCREW, TWELVE POINT CAP	bolt
3177945	SCREW, HEX FLANGE HEAD CAP	bolt
3628452	SCREW, HEXAGON HEAD CAP	bolt
S-112	SCREW, HEXAGON HEAD CAP	bolt
205684	BRACKET, LIFTING	bracket_lifting
205230	BUSSING	bushing
0300-4623-29	DFLB (600V)	current_transformer
0300-4623-30	DFLC (600V)	current_transformer
0300-4623-52	DFLB BR (0-480V)	current_transformer
0300-4623-54	DFLC BR (0-480V)	current_transformer
3178803	CYLINDER BLOCK OPTION BP6089	cylinder_block
3178910	CYLINDER BLOCK	cylinder_block
148582	DOE, PIN	dowel_pin
70662	DOE, PIN	dowel_pin
3629497	DRAINCOCK	draincock
206224	PLUG, EXPANSION	expansion_plug
206742	PLUG, EXPANSION	expansion_plug
3629168	PLUG, EXPANSION	expansion_plug
122-0757	Filter. Water - W/Corosion Inhibiting Chemical	filter
159-1445	Reservoir, Fuel	fluid
FS1216	Fuel/Water Sep Spin-On	fuel_filter
121-0113	Gasket, Pump	gasket
121-0117	Gasket, Hand Hole	gasket
205059	WASHER, PLAIN	gasket
3002993	DOE, RING	gasket
3025485	WASHER, PLAIN	gasket
3176857	DOE, RING	gasket
3178450	WASHER, PLAIN	gasket
3178457	WASHER, PLAIN	gasket
M-4352581	Upper Gasket Set	gasket
S-604	WASHER, LOCK	gasket
S-610	WASHER, LOCK	gasket
338-2278	Harness. Wiring - AC (Includes Terminal Block & Cable Ties) [Used only with meters]	harness
338-2529	Harness. Wiring	harness
128-0108	Insulation, Hose - Bulk (7/8º ID) (Order By The Foot - 10 Feet Required)	hose
130-5588-02	Tube, Water Heater	hose
130-5589-02	Tube, Water Heater	hose
130-5590-02	Tube, Water Heater	hose
130-5591-02	Tube, Water Heater	hose
338-2925	Hose, Radiator	hose
501-0704	Line, Flexible Fuel - Fuel Out	hose
501-0707	Line, Flexible Fuel - Fuel In	hose
502-1162	Connector, Hose (3/8")	hose
503-0183	Clamp, Hose	hose
503-0685	Clamp, Hose	hose
503-0868	Clamp, Hose - T-Bolt Type (3.5" NON)	hose
503-1140	Hose, Rubber	hose
503-1484	Elbow, Hose (45 Deg) (7" ID)	hose
503-1620	Hose – Bulk (3/8" ID) (Order by the Foot)	hose
503-1727	Hose, Radiator (3” ID x 10”)	hose
503-1728	Hose (3” ID x 5–1/2”)	hose
503-1870-11	Clamp, Hose	hose
503-1870-12	Clamp, Hose	hose
505-0324	Hose. Bulk (Sold by the Foot) Two Feet Required Nipple, Pipe - Half (3/4 NPT x 2"LG)	hose
98-5759	Drive - Multi Groove Hose, Flexible - Lube (Grease)	hose
98-5842	Clamp, Hose - T-Bolt Type (3.5" NON)	hose
3822575	Injector and valve adjustment kit	injector
3011884	INSERT, LINER	insert_liner
3019150	INSERT, LINER	insert_liner
3021148	INSERT, LINER	insert_liner
206580	BEARING, MAIN	main_bearing
206581	BEARING, MAIN A/R No.2,3,4,5,6,7,&8, Upper	main_bearing
206582	BEARING, MAIN A/R No.2,3,4,5,6,7,&8, Upper	main_bearing
206583	BEARING, MAIN A/R No.2,3,4,5,6,7,&8, Upper	main_bearing
206584	BEARING, MAIN A/R No.2,3,4,5,6,7,&8, Upper	main_bearing
206590	BEARING, MAIN	main_bearing
206591	BEARING, MAIN A/R No.2,3,4,5,6,7,&8, Lower	main_bearing
206592	BEARING, MAIN A/R No.2,3,4,5,6,7,&8, Lower	main_bearing
206593	BEARING, MAIN A/R No.2,3,4,5,6,7,&8, Lower	main_bearing
206594	BEARING, MAIN A/R No.2,3,4,5,6,7,&8, Lower	main_bearing
206600	BEARING, MAIN	main_bearing
206601	BEARING, MAIN A/R No.1&9, Upper	main_bearing
206602	BEARING, MAIN A/R No.1&9, Upper	main_bearing
206603	BEARING, MAIN A/R No.1&9, Upper	main_bearing
206604	BEARING, MAIN A/R No.1&9, Upper	main_bearing
206610	BEARING, MAIN	main_bearing
206611	BEARING, MAIN A/R No.1&9, Lower	main_bearing
206612	BEARING, MAIN A/R No.1&9, Lower	main_bearing
206613	BEARING, MAIN A/R No.1&9, Lower	main_bearing
206614	BEARING, MAIN A/R No.1&9, Lower	main_bearing
3018210	SET, MAIN BEARING STANDARD	main_bearing_set
3018211	SET, MAIN BEARING A/R .010 Inch O/S	main_bearing_set
3018212	SET, MAIN BEARING A/R .020 Inch O/S	main_bearing_set
3018213	SET, MAIN BEARING A/R .030 Inch O/S	main_bearing_set
309-0561	Alternator & Drive Components Group Pulley. Alternator - Multi Groove (Use with 35 A MP Alternator)	oil_filter
LF3325	Lube, Full-Flow Spin-On	oil_filter
016-40820	Harness, Wiring (Includes Cable Ties and Terminals)	other_service
102-1335	Plug, Oil Drain	other_service
121-0116	Cover, Hydraulic Hole	other_service
130-2981	Cap. Radiator - 7#PSI	other_service
130-3538	Chemical DCA4 Service Pre-Charging Complete System	other_service
130-3576	Decal - Ground	other_service
130-3758	Radiator (includes Cap)	other_service
140-1260	Fitting, Safety Filter	other_service
140-1548	Indicator, Service	other_service
140-2098	Hood, Air Inlet (Includes Mounting Clamp)	other_service
140-2099	Band	other_service
140-2395	Tube, Air Inlet	other_service
140-2504-01	Bracket - Right Side	other_service
140-2504-02	Bracket - Left Side	other_service
140-2508	Tube, Air Inlet	other_service
140-2509	Tube, Air Inlet	other_service
140-2515	Bracket, Mounting	other_service
140-2519	Tube, Air Inlet	other_service
140-2521	Tube, Air Inlet	other_service
140-2528	Shield	other_service
191-1926-02		other_service
300-2856	Board Assy, Printed Circuit	other_service
300-2863	Board Assy, Printed Circuit - Relay Assembly- (A14)	other_service
3007525	Liner Kit STD	other_service
301-9054-01	Decal - Panel Front Markings (Control With Meters)	other_service
301-9054-02	Clip - Fastener	other_service
301-9054-03	Clip - Fastener	other_service
3012611	Liner Kit +.010" UPF	other_service
3012612	Liner Kit +.020" UPF	other_service
302-1720	Meter, Frequency (M23)	other_service
302-1753	Ammeter (M22) See Current Transformer & Ammeter Installation Figure for Parts)	other_service
302-1800	Ammeter (M22) Scale in Amps as Indicated 0-2000/0-4000 (600 VAC Application) 0-3000/0-6000 (120-480 VAC Application)	other_service
302-1908	Screw. Cap - Hex Head (M8-1.25 x 35MM)	other_service
305-0818-02	EOOO-21002	other_service
307-1056	Relay. 24 VDC	other_service
307-1987	Clip. Relay	other_service
308-0882	Decal - Panel Front Markings (Control Without Meters)	other_service
309-0436	Switch, Thermostatic - High Water Temperature (PRE-ALARM)(216"F) Switch. Thermostatic - High Water Temperature (SHUTDOWN)	other_service
309-0437	(222"F)	other_service
309-0635-02	Valve, Check	other_service
3096680	Piston STC 13.8:1 Ratio	other_service
3096681	Piston KT Series 15.5:1 Ratio	other_service
3096682	Piston KTA Series 14.5:1 Ratio	other_service
3096683	Piston 13.5:1 Ratio	other_service
3096684	Piston KTA 15.7:1 Ratio	other_service
3096685	Piston STC 13.9:1 Ratio	other_service
319-0447	Bracket. Mounting - Relay	other_service
319-0754	Tie. Cable	other_service
322-0363	Component 322-0363	other_service
323-0804	Screw. Machine - Round Head with IT Lock Washer (#6-32 x 1/2")	other_service
323-1200	# Socket, Contact (Used in J1, J2)	other_service
323-1304	tiotming, Umector	other_service
323-1306	Genset component (SJB series)	other_service
3318201	Battery Cable Group	other_service
332-0052	Clamp, Loop	other_service
332-0607	Block, Terminal (T81)	other_service
332-1279	Terminal. Lug - Ring (3/8	other_service
332-1292	Terminal Board (Includes Parts Marked #)	other_service
332-1445	Tie. Cable	other_service
332-1673	Terminal, Wire - Spade	other_service
332-2634	Clamp, Retainer 4 Prior To December 1996 Production (Mounted On Top And Side Of Control Box Wrapper)	other_service
332-2723	Strip. Marker	other_service
333-0677-01	Heater, Coolant - 4990 Watt	other_service
333-0677-02	Heater, Coolant - 6420 Watt	other_service
338-1835	Harness, Wiring (A13 to A l l )	other_service
338-1836	Harness, Wiring (A14 to A l l )	other_service
338-1904	Harness. Wiring (A15 to All)	other_service
338-2532	Terminal. Lug - Forked (No. 6 Screw)	other_service
355-0093	Voltmeter (M21) Dual Scale 0-300/0-600V Single Scale 0-750V	other_service
3628731	Piston STC Kit	other_service
3630913	Piston KTA-50-G7	other_service
3631241	Piston Kit STC 13.9:1 Ratio	other_service
3631242	Piston Kit 13.5:1 Ratio	other_service
3631243	Piston Kit KTA 15.7:1 Ratio	other_service
3631244	Piston Kit KTA Series 14.5:1 Ratio	other_service
3631245	Piston Kit KT Series 15.5:1 Ratio	other_service
3631246	Piston Kit STC 13.8:1 Ratio	other_service
3801268	Liner Kit +.030" UPF	other_service
3803530	Piston Assembly STC	other_service
3804747	Piston Kit KTA-50-G7	other_service
3804885	Piston KTA-50-G8/G9	other_service
406-0333	Component 406-0333	other_service
406-0334	Clip, Retaining - Turnbutton Fastener	other_service
4089847	Piston Kit GTA38/19	other_service
4090013	Piston Kit KTA-38-M2	other_service
4090029	Piston Kit QSK19CE	other_service
4090181	Piston GTA38/19	other_service
4097889	Piston KTA-38-M2	other_service
4910463	Piston QSK19R/M	other_service
4910465	Piston QSK Series	other_service
4916177	Piston GTA/GQSK19	other_service
4918058	Piston QSK19CE	other_service
4922319	Piston QSK19C	other_service
4955233	Piston Kit QSK19R/M	other_service
4955235	Piston Kit QSK Series	other_service
4955236	Piston Kit QSK19C	other_service
4955238	Piston Kit GTA/GQSK19	other_service
501-0520	Screw, Cap - Hex Head (3/8-24 x 5/8")	other_service
501-0524	Washer, Lock - EIT (3/8")	other_service
501-0558	Line. Flexible - Bypass	other_service
503-1717	Elbow, Reducer (45 Deg) (7" ID to 6" ID)	other_service
503-1720	Insert, Reducer (6" OD to 5-1/2" ID)	other_service
503-1730		other_service
504-0028	Valve, Radiator Drain	other_service
505-0007	Belt. Drive - Multi Groove (Used with 35 A MP Alternator * Pulley, Alternator - Multi Groove (Use with 75 A MP Alternator)	other_service
505-0017	Bushing, Pipe – Reducer (3/8" to 1/4")	other_service
505-0021	Bushing, Pipe - Reducer (3/4º to 1/2º)	other_service
505-0100	Nipple, Pipe - Close (1/2”)	other_service
505-0102	Filter. Water - W/Corosion Inhibiting	other_service
505-0117	Bushing, Reducer - Flush, Brass (1/2' NPT x3/8° NPT)	other_service
505-0132	Nipple, Pipe - Close (3/4 NPT x l-3/8"LG) Elbow. Pipe - 90* (3/4 NPT)	other_service
505-0376	Elbow – 45 Deg (3/8")	other_service
508-0015	Washer, Insulating - Fiber (#8)	other_service
511-0161-02	.*	other_service
517-0131	Capacitor (Used across Voltmeter Terminals on some Sets)	other_service
518-0548-24	Clamp, Retainer Begin December 1996 Production (Mounted On Top And Side Of Control Box Wrapper On The Side Towards The Control Box Cover)	other_service
518-0548-42	Clamp, Retainer 4 Prior To December 1996 Production (Mounted On Top And Side Of Control Box Wrapper)	other_service
526-0030	Washer, Flat (3/8")	other_service
800-0055	Screw, Cap – Hex Head (3/8–16 x 2-1/4")	other_service
800-0062	Nut, Insulated	other_service
800-0094	Screw, Cap – Hex Head (1/2–13 x 2")	other_service
800-0270	DCA4 Service Pre-Charging Complete System	other_service
800-2060	Screw, Cap - Hex Head (M8x 1.25 x35)	other_service
809-0035	Screw, Machine - Thread Cutting, Round Head (#8 X 3/4')	other_service
812-0063	Screw, Machine - Round Head	other_service
812-0065	Screw, Machine - Round Head (#6 - 32 x 5/8')	other_service
812-0084	Screw, Machine - Round Head (#8-32 x 1)	other_service
815-0388	Bracket. Mounting - Relay Lead(s), Electrical Wire, Electrical - 20 AW G, Insulated Terminal, Wire - Forked, 18-20 Gauge	other_service
815-0544	Screw, Machine - Round Head IT Washer (#6 - 32 x 1/2')	other_service
821-0004	Screw, Self-Locking - Hex	other_service
821-0029	Screw, Self–Locking – Hex Washer Head (3/8–16 x 3/4")	other_service
821-0033	Screw, Self–Locking – Hex Washer Head (7/16–14 x 3/4")	other_service
821-5004-03	Screw, Self-Locking – Hex Washer Head (3/8–16 x 1")	other_service
850-0050	Washer, Lock - Spring (3/8”)	other_service
853-0003	Washer, Lock - ET (#6)	other_service
856-0008	Washer, Lock - EIT (5/16'1)	other_service
856-0010	Washer, Lock - EIT (3/8')	other_service
870-0131	Nut. Hex - with ET (#10-32)	other_service
870-0196	Nut, Insulating (#8)	other_service
870-0281	Nut, Self-Locking – Hex Washer Head (3/8–16)	other_service
900-0181	PCC Control Service Manual	other_service
960-0602		other_service
960-0606		other_service
960-0608		other_service
98-2235		other_service
98-4732	Caution	other_service
98-4798	Decal - Caution "7# PSI HOT WATER SYSTEM"	other_service
98-5298	Decal - Panel Rear Markings (All Control Panels)	other_service
98-5299	Decal - Panel Rear Markings (All Control Panels)	other_service
98-5316	Decal - Panel Rear Markings (All Control Panels)	other_service
98-5387	Nut, Self-Locking - with ET Lockwasher (#10-32)	other_service
98-5393	Screw, Tapping - Round Head (#8 x 3/4")	other_service
98-5822	Bushing, Reducer - Flush (1/2 NPT x 3/8 NPT)	other_service
98-6108-03	Decal - Model Identification	other_service
98-6111-03	ONAN GEN SET CUMMINS GEN SET	other_service
98-6139-03	CUNMINS ONAN GEN SET	other_service
98-6169	Terminal Assembly (Includes Replaceable Items 26 thru 29)	other_service
F-2375	A single line drawing of the prime power system	other_service
M-3804747	Piston Kit	other_service
68445	PIN, GROOVE	pin
3628605	PLUG, PIPE	pipe_plug
3628607	PLUG, PIPE	pipe_plug
3178464	PLATE, COVER	plate_cover
121-0111	Drive, Pump	pump
159-1451	Pump, Fuel Transfer	pump
3011076	SEAL, D RING	seal
3014668	SEAL, D RING	seal
3081489	SEAL, OIL	seal
3177556	SEAL, RECTANGULAR RING	seal
509-0283-01	Seal	seal
509-0336	Seal, O-Ring	seal
509-0337	Seal, O-Ring	seal
149-2232	Indicator, Air Restriction (Includes Fitting)	sensor
193-0244	Sender, Pressure - 0i1	sensor
193-0375	# Sender, Water Temperature	sensor
309-0269	Switch, Low Engine Temperature (S4)	sensor
960-0181		service_manual
960-0302		service_manual
960-0504	PCC Control Service Manual	service_manual
960-0507	Detector Control Service Manual	service_manual
3033853	SHAFT, IDLER	shaft_idler
3175281	SHAFT, IDLER	shaft_idler
205741	SHIM, A/R .007 Inch O/S	shim
205742	SHIM, A/R .008 Inch O/S	shim
205743	SHIM, A/R .009 Inch O/S	shim
205744	SHIM, A/R .020 Inch O/S	shim
205745	SHIM, A/R .031 Inch O/S	shim
3000138	SUPPORT, BEARING	support_bearing
309-0649	Thermostat	thermostat
3000139	BEARING, THRUST	thrust_bearing
3001708	BEARING, THRUST A/R .010 Inch O/S	thrust_bearing
3001709	BEARING, THRUST A/R .020 Inch O/S	thrust_bearing
3001710	BEARING, THRUST A/R .030 Inch O/S	thrust_bearing
3001711	BEARING, THRUST A/R .040 Inch O/S	thrust_bearing
3179664	VALVE, PISTON COOLING	valve_piston_cooling
508-0292	Washer, Sealing - Copper	washer

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 KTA50 / KTTA50?

The Cummins/Onan KTA50 / KTTA50 engine has an oil capacity of 169.0 liters.

Which generators use the Cummins/Onan KTA50 / KTTA50 engine?

The Cummins/Onan KTA50 / KTTA50 powers 1 generator set(s), including Cummins/Onan DFM.

How often should you change the oil in the Cummins/Onan KTA50 / KTTA50?

The Cummins/Onan KTA50 / KTTA50 oil change interval is every 250 hours.

What is a common problem with the Cummins/Onan KTA50 / KTTA50 engine?

A commonly reported issue on generators using the Cummins/Onan KTA50 / KTTA50 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..