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Cummins/Onan M11 Engine

The Cummins/Onan M11 is a 10.8 L 6-cylinder engine rated at 2100 rpm. It powers generator sets from Cummins/Onan, including the DQAA, DQAB, M1i Series Engines and ps200da. It holds 34 L (9.0 gal) of oil and 12.9 L (3.4 gal) of coolant.

Also known as: Cummins M11

10.8 L

Displacement

Cylinders

2100 rpm

Rated speed

34.0 L

Oil capacity

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

Engine specifications

Oil capacity	34.0 L
Coolant capacity	12.9 L
Displacement	10.8 L
Cylinders	6
Rated speed	2100 rpm

Generator sets powered by this engine

Cummins/Onan DQAA Cummins/Onan DQABCummins/Onan M1i Series EnginesCummins/Onan ps200da

This engine also powers 5 machine(s) on Power Equipment Info.

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

Common problems

Fuel Consumption — Excessive
Fix: Verify Complaint
Engine Will Not Crank or Cranks Slowly (Electric Starting Motor)
Cause: Engine Drive Units Engaged Battery Connections Broken, Loose, or Corroded Battery Charge Low Battery Rating Too Low Oil for Operating Conditions Incorrect Battery Temperature Too Low
Fix: Disengage engine driven units. Check for damage. Clean and tighten If necessary. Check electrolyte level and specific gravity. Recharge or replace batteries. Replace battery with correct rating. Change oil and filters. Use the type recommended (15W-40). Check operation. Check battery heater operation. Refer to the manufacturer's instructions.
Engine Will Not Crank or Cranks Slowly (Air Starting Motor)
Cause: Air Pressure Insufficient in Air Tank Engine Drive Units Engaged Oil Incorrect for Operating Conditions
Fix: Increase pressure using external air supply. Disengage engine driven units. Change oil and filters. Use the type recommended (18W-40). Check operation.
Engine Vibration Excessive
Cause: Refer to symptom tree Engine Runs Rough or Engine Misfiring Engine Idie Speed TooLow Fan is Loose, Damaged or Unbalanced Engine Belt Driven Accessories Malfunctioning: Fan Hub, Alternator, Freon Compressor, Hydraulic Pump or Air Compressor Engine Mounts Worn or Defective
Fix: Misfires. Adjust idle speed. Check fan. Visually check engine mounts.
Engine Starts But Will Not Keep Running
Cause: Fuel Level in Tank TooLow Engine Driven Units Engaged Check for air in fuel. Tighten fuel connections. Air in the Fuel System Fuel Filter Plugged or Fuel Waxing Due to Cold Weather Fuel Suction Line Restricted Fuel Contaminated Intake or Exhaust System Restricted
Fix: Add fuel. Disengage engine driven units. Verify by operating engine from a temporary supply tank. Inspect fuel line for restriction. Replace fuel filter. Check intake and exhaust restriction.
Engine Speed Surges at Low Idle
Cause: Fuel Level Low inthe Tank Fuel Inlet Restriction or Airin the Fuel Return Fuel Line Restricted or Plugged
Fix: Fill supply tank. Tighten the fuel line connections and filter(s). Replace fuel drain line.
Engine Speed Surges (Other Than Low Idle)
Cause: Fuel Level Low inthe Tank Fuel Inlet Restriction or Airin the Fuel
Fix: Fill supply tank. Tighten the fuel line connections and filter(s).
Engine Shuts Off Unexpectedly or Dies During Deceleration
Cause: Engine Will Not Restart Fuel Inlet Restriction or Air in the Fuel Low Battery Voltage Fuel Shutoff Solenoid Voltage Low. Fuel Shutoff Valve Closed
Fix: Refer to symptom chart Engine Will Not Start Check fuel tanks, fuel filter, fuel lines, connections, and fuel cooling plate. Check battery power supply circuits. Check fuel shutoff solenoid valve circuit.
Engine Cranks But Will Not Start (No Smoke From Exhaust)
Cause: Fuel in Tank Too Low
Fix: Add fuel
Engine Acceleration and Response Poor
Cause: Vehicle Drive Train not Correctly Matched to Engine
Fix: Review specification of engine and drive train components.
Crankcase Gases (Blowby) — Excessive
Cause: Crankcase Breather Vent Tube Restricted
Fix: Check breather tube restriction.
Coolant Temperature Below Normal
Cause: Continuously Operating in Low Ambient Temperature
Fix: Refer to Cold Weather Operation, Bulletin No. 3387266-R.
Coolant Temperature Above Normal — Sudden Overheat
Fix: Inspect for external leaks on engine and radiator. Make repairs as necessary. Add coolant.
Coolant Temperature Above Normal — Gradual Overheat
Cause: Coolant Level Low
Fix: Inspect for external leaks on engine and radiator and make repairs. Add coolant.
Coolant Loss — External
Fix: Check coolant level. Refer to the manufacturer en. sid. en for specifications,

Compiled from service & troubleshooting documentation across every generator set that uses the Cummins/Onan M11.

Maintenance schedule

Item	Capacity	Part #	Interval
Air filter		3666075	6000 hr	Amazon eBay $129.80
Fuel filter		—	6000 hr
Oil filter		—	6000 hr
Battery		—	6000 hr
Belt		—	6000 hr
Coolant		—	6000 hr
Coolant filter		—	6000 hr
Oil	2.6 liters [0.7 U.S. gallon]	—	6000 hr
Spark plug		—	6000 hr

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

Repair guides

Step-by-step procedures compiled from the Cummins/Onan service manual for this engine.

Service intervals

Item	Action	Hours	Months	Notes
Air compressor air cleaner element	Replace	250 hr
Coolant filter	Change	250 hr	6 mo	Do not change if SCA concentration level is over 3 units
Fuel filter	Change	250 hr	6 mo	Whichever comes first
Lubricating oil	Change	250 hr	6 mo	Standby generator applications: 250 hours or 12 months, whichever comes first
Lubricating oil filter	Change	250 hr	6 mo
Engine	Clean	1500 hr		Steam clean
Engine mounting bolts	Check	1500 hr		Check torque
Shutters and thermatic fans	Check	1500 hr		If equipped
Turbocharger mounting nuts	Check	1500 hr		Check torque
Valves and injectors	Adjust	1500 hr		Adjust when engine is cold (60 C or below)
Water pump	Inspect	1500 hr		Check weep hole for leakage
Air compressor	Inspect	6000 hr
Coolant and antifreeze	Change	6000 hr	24 mo
Cooling system	Clean	6000 hr	24 mo	Whichever comes first
Fan hub	Inspect	6000 hr
Fan idler pulley assembly	Inspect	6000 hr
Fuel pump	Clean	6000 hr		Clean and calibrate
Injectors	Clean	6000 hr		Clean and calibrate
Turbocharger	Inspect	6000 hr
Vibration damper	Inspect	6000 hr
Rupture basin leak detect switch	Test		12 mo	Check once a year; in some areas weekly inspections may be required by safety code regulations
Supplemental Coolant Additive (SCA) concentration	Check		6 mo	At least twice a year

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	Angular alignment maximum T.I.R.	0.001	inch per inch of radius (center of shaft to indicator axis)	measuring deflection to bolt heads
Clearance	Fan hub end clearance	0.08 MIN / 0.41 MAX	mm
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
Clearance	Turbocharger axial clearance	0.038 MIN / 0.089 MAX	mm
Clearance	Turbocharger radial bearing clearance	0.15 MIN / 0.64 MAX	mm
Gap	Air compressor discharge line carbon deposit thickness (maximum)	1.6	mm
Gap	MPU sensor to flywheel ring gear tooth	back it out one quarter turn	turn	sensor threaded in until it just touches gear tooth
Other	Angular alignment maximum T.I.R.	.001 inches per inch of radius	in/in	center of shaft to indicator axis
Other	Battery specific gravity, fully charged	approximately 1.260	specific gravity	at 80 F (27 C)
Other	Fuel lift height limit	6	feet	(1.8 meters) between fuel lift pump and bottom of dip tube
Other	GOV GAIN default value for paralleling applications	70	%
Other	Maximum cranking voltage drop	2	volts	difference between battery and starter terminals while cranking
Other	REG VHZ (underfrequency roll-off) adjustable range	1 through 50; normal range 7 through 21
Other	Start delay adjustment range	0 to 300	seconds
Other	Stop delay adjustment range	0 to 600	seconds
Other	Under-frequency roll-off threshold (UFRO)	typically 59 Hz for 60 Hz applications and 49 Hz for 50 Hz applications	Hz	AVR UFRO pot preset
Pressure	Cylinder block coolant pressure, closed thermostat	138 minimum / 275 maximum	kPa	1800 rpm - no load / closed thermostat
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	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 service limit while cranking	10	psi	service lubricating system if below
Pressure	Low oil pressure shutdown threshold	14	psi	less than this value shuts down
Pressure	Lubricating oil pressure at 1200 rpm or torque peak (minimum allowable)	207	kPa	at 1200 rpm or torque peak
Pressure	Lubricating oil pressure, low idle (minimum allowable)	70	kPa	low idle
Pressure	NTA 855 engine normal oil pressure	35-50	psi (241-345 kPa)	normal run
Pressure	NTA 855 oil pressure shutdown limit	25	psi (172 kPa)	run mode value
Pressure	NTA 855 oil pressure shutdown limit	8	psi (55 kPa)	idle mode value
Pressure	NTA 855 oil pressure warning limit	12	psi (83 kPa)	idle mode value
Pressure	NTA 855 oil pressure warning limit	30	psi (207 kPa)	run mode value
Pressure	Oil pressure - K19 engine idle	20	psi (138 kPa)	idle
Pressure	Oil pressure - K19 engine normal	50-70	psi (345-482 kPa)	normal operating
Pressure	Oil pressure - K38 engine idle	20	psi (138 kPa)	idle
Pressure	Oil pressure - K38 engine normal	45-65	psi (310-448 kPa)	normal operating
Pressure	Oil pressure - K50 engine idle	20	psi (138 kPa)	idle
Pressure	Oil pressure - K50 engine normal	50-70	psi (345-482 kPa)	normal operating
Pressure	Oil pressure - L10/M11 engine idle	15	psi (103 kPa)	idle
Pressure	Oil pressure - L10/M11 engine normal	30-50	psi (207-345 kPa)	normal operating

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	50/50 mixture of good quality water and fully formulated antifreeze (40 to 60% working range)	TMC RP 329 (ethylene glycol) or TMC RP 330 (propylene glycol)		12.9 liters	Use ethylene glycol antifreeze year-round. 50/50 mixture gives -36 C freeze point and 110 C boiling point. SCA concentration must not fall below 1.2 units or exceed 3 units per gallon of cooling system capacity.
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	SAE 15W-40 multi-viscosity (arctic: synthetic CE/SF 5W-20 or 5W-30)	API CG-4 or CF-4		39.0 liters	Cummins Premium Blue or equivalent. Sulfated ash limit 1.85 mass percent (1.0 suggested). Total system capacity including filter approximately 39 liters [10.3 U.S. gal]; oil pan capacity 34 liters [9 U.S. gal]; filter capacity 2.6 liters [0.7 U.S. gal].
Fuel	ASTM No. 2 D diesel (blends of No. 2 D and No. 1 D below 0 C)	ASTM No. 2 D			Viscosity must be kept above 1.3 cSt at 40 C. Do not mix gasoline or alcohol with diesel fuel.
Fuel	Diesel				Day tank fuel transfer pump maintains reservoir of diesel fuel in the day tank.
Grease	Lithium based grease	Mobilux No. 2 or Shell Alvania R3		2.74 oz (81 ml)	Generator end bearing. Temperature range -22F to +248F (-30C to +120C). Grease should be equally divided between the bearing, bearing cap cavity, and bearing cartridge cavity.
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.

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	Indicates local or remote Emergency Stop.	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. Can be reset only at the PCC front panel.
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, lines and filters; replenish if low; reset control and restart.
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	Reduce load if possible; check air inlets and outlets and remove obstructions to airflow.
212	HIGH COOLANT TEMP	Indicates engine has overheated (coolant temperature has risen above the shutdown trip point: 215 F (102 C) - standby or 207 F (97 C) - primary).	Shutdown	Check for obstructions to cooling airflow; check fan belt; check coolant mixture; check blower fan and circulation pumps; reset control and restart.
213	COOLANT SENDER	Resistance of the coolant temperature sender is out of range.	Warning	Check the resistance of the sender; should be 500 to 2k ohms.
214	LOW COOLANT LVL	Indicates engine coolant level has fallen below the trip point.	Warning	Check coolant level in radiator and coolant recovery bottle; replenish if low; look for leaks.
215	LOW COOLANT LVL	Indicates engine coolant level has fallen below the trip point.	Shutdown	Allow engine to cool; check coolant level and leakage points; reset control and restart.
220	MAG PICKUP	Mag pickup speed indication is not being sensed or does not match generator set 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	Check fuse F3 on the Engine Interface board; check battery cable connections; recharge or replace the battery.
222	OVERCRANK	Possible fuel system problem.	Shutdown	Check for empty fuel tank, leaks, plugged fuel lines; replace dirty fuel or air filter; reset and restart.
223	OVERSPEED	Indicates engine has exceeded normal operating speed. (115% ±1% of nominal).	Shutdown	Check mechanical fuel linkage and governor module/digital board duty cycle.
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 LOW DC VOLTAGE 230.
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 the initial start setup procedure; if the set shuts down on the same EEPROM ERROR message, replace the digital board (A32).
251	EEPROM ERROR	PCC memory error; data corruption of noncritical operating parameters.	Warning	Perform the adjustment procedures; if the same message occurs, perform calibration procedures; if the message persists, replace the digital board (A32).
252	EEPROM ERROR	PCC memory error; data corruption of noncritical operating parameters.	Warning	Verify values/choices selected and repeat the save operation; if the same message occurs, replace the digital board (A32).
260	CUSTOMER FAULT 1	When this customer defined input is closed to ground, the corresponding fault message is displayed. Programmable to initiate a shutdown or a warning.	Warning	Isolate source of false signal; repair external wiring or replace A34.
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	Isolate source of false signal; repair external wiring or replace A34.
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	Isolate source of false signal; repair external wiring or replace A34.
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	Isolate source of false signal; repair external wiring or replace A34.
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	Set display to GEN, VOLTS, L-N; determine if the output voltage the control sees is low or high; isolate PCC/alternator/excitation circuit.
303	LOW AC VOLTAGE	One or more phase voltages dropped below 85% of nominal for 10 seconds.	Shutdown	Check PMG/field wiring, rotating rectifier, load and connectors.
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	Check fuel supply, intake air supply and load.
320	OVERCURRENT	Indicates that generator output current has exceeded 110% of rated for 60 seconds.	Warning	Check load and load lead connections.
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	Check load and load lead connections.
322	SHORT CIRCUIT	Indicates that generator output current has exceeded 175% of rated.	Shutdown	Check load and load lead connections.
330	OVERLOAD	Three-phase power output exceeds 105% of standby (or 115% of prime) rating.	Warning	Check load and load lead connections.
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 (Red)	Engine shut down because of a customer-connected system fault; part of a 10 second time delay shutdown circuit.	Shutdown	Service as required by the customer-supplied fault indicating switches.
FAULT 2	Fault 2 (Red)	Engine shut down because of a customer-connected system fault; part of a non-time delay shutdown circuit.	Shutdown	Service as required by the customer-supplied fault indicating switches.
GF	Ground Fault Alarm (Optional)	Ground fault relay monitors neutral to ground connection and line to neutral, activating a fault alarm when the connection is broken or a ground fault is sensed.	Warning	Clear fault condition by pushing the Run/Stop (Reset)/Remote switch to Reset (auto reset link set at factory).
HET	High Engine Temperature (Red)	Engine shut down because of excessively high engine coolant temperature (greater than 230 deg F).	Shutdown	Check coolant level and leaks; service cooling system; reset engine control.
LET	Low Engine Temperature (Yellow)	Engine temperature is less than 70 deg F and the engine might not start.	Warning	Plug in, repair or install engine coolant and oil heaters.
LOP	Low Oil Pressure (Red)	Engine shut down because of excessively low engine oil pressure (less than 14 psi).	Shutdown	Check oil level and oil leaks; service lubricating system; reset engine control.
LOW FUEL	Low Fuel (Yellow)	Fuel level in the supply tank has dropped below the reserve necessary to run the set at full load for the prescribed number of hours.	Warning	Fill the main fuel supply tank with the appropriate grade of fuel.
OC	Overcrank (Red)	Engine shut down because it did not start during the timed cranking period (approximately 75 seconds, including two rest periods).	Shutdown	Service the set as necessary; reset engine control.
OS	Overspeed (Red)	Engine shut down because of overspeed.	Shutdown	Adjust the Electronic Overspeed Module; check governor for binding; reset engine control.
PRE-HET	Pre High Engine Temperature (Yellow)	Engine coolant temperature is abnormally high (greater than 220 deg F).	Warning	Shut down if possible or disconnect non-critical loads; service cooling system.
PRE-LOP	Pre Low Oil Pressure (Yellow)	Engine oil pressure is abnormally low (less than 20 psi).	Warning	Shut down if possible or disconnect non-critical loads; service lubricating system.
RUN	Run (Green)	Generator set is running and the starter has been disconnected.	Info
SWITCH OFF	Switch-off (Flashing Red)	The Run/Stop/Remote switch is in the Stop position, preventing remote automatic operation.	Info	Push the Run-Stop-Remote switch to Remote.

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 adjustment

⚠ Accidental starting of the generator set during this procedure presents the hazard of severe personal injury or death. Make sure to disconnect the negative (-) battery cable(s) before beginning.

Tools: Dial indicator, Wooden shims

Disconnect the negative (-) battery cable(s) before beginning.
Fasten a dial indicator to the generator shaft or cooling fan with sensing point on capscrew head or flat surface of drive disc at 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.
Record maximum positive and negative dial indicator readings as the engine completes one revolution.
T.I.R. equals the sum of the maximum positive and negative readings.
Maximum T.I.R. should not be more than .001 inch for each inch of radius.
Remove equal shims from under both generator mounting feet to lower the generator.

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.

Drive Belt, Alternator - Adjust adjustment

Tools: Belt tension gauge, Part No. ST-1293

Loosen the adjusting screw locknut.
Loosen the adjustment link locking capscrew.
Loosen the pivot capscrew and nut.
Use belt tension gauge, Part No. ST-1293, to measure belt tension.
Turn the alternator adjusting screw clockwise to tighten the belt.
Tighten the adjusting screw locknut against the retainer and the adjustment link locking capscrew.
Tighten the pivot capscrew and nut.

Drive Belt, Cooling Fan - Adjust adjustment

⚠ Do not adjust belt tension to full value with the adjusting screw. Belt tension can increase when the locknut is tightened and cause reduced belt and bearing life.

Tools: Belt tension gauge, Part No. ST-1293

Loosen the idler pulley shaft locknut.
Use belt tension gauge, Part No. ST-1293, to adjust the belt to the correct tension.
Tighten the idler pulley shaft locknut.
Check the belt tension again to make sure the belt is not too tight.

Governor Calibration Checks adjustment

Tools: Frequency meter or tachometer, Jumper wire

Start the generator set.
Adjust engine no-load speed to the desired allowable speed droop using the Run Speed potentiometer.
With no load, turn GAIN clockwise slowly until engine speed oscillates.
Reduce GAIN slowly counterclockwise until engine speed is stable.
Upset the governor by momentarily shorting terminals 7 and 10 on the governor control.
Apply and remove loads to check generator set response.

HC4-7 Axial Alignment Procedure adjustment

Tools: Dial indicator with magnetic base or clamp

Check only when an objectionable vibration is present.
Fasten dial indicator holding device to skid base, engine block, or generator shell with magnetic base or clamp.
Position sensor point on the generator shaft hub.
Bar the engine over in a clockwise rotation as viewed from engine flywheel through a couple of rotations.
Record indicator readings in eight equally spaced points around the shaft diameter.
Remove the capscrews connecting drive discs and flywheel and mark discs and flywheel.
Rotate engine or generator so drive disc holes are repositioned 180 degrees from original location.
Put capscrews back in and retorque. Recheck shaft alignment.
If runout unchanged, rotate discs to 30, 60 or 90 degrees from original location.
If T.I.R. does not improve, inspect flywheel pilot and drive disc runouts.

Overhead Set - Adjust Valves and Injectors (STC) adjustment

⚠ Do not pull or pry on the fan to manually rotate the crankshaft.

⚠ An overtightened setting on the injector adjusting screw will produce increased stress on the injector train and the camshaft injector lobe.

Tools: STC tappet adjusting tool, Part No. 3823348, Torque wrench, Part No. 3376592, Torque wrench adapter, Part No. ST-669, Feeler gauges

Remove the crankcase breather tube from the crankcase breather outlet.
Remove the 16 capscrews, isolators, and spacers from the cover.
Remove the rocker lever cover and gasket.
Rotate the accessory drive shaft clockwise until the A valve set mark aligns with the pointer.
Loosen the injector adjusting screw locknut and tighten the adjusting screw until clearance is removed; then one additional turn to seat the link.
Loosen the adjusting screw until the STC tappet touches the top-cap of the injector.
Place the STC tappet adjusting tool, Part No. 3823348, on the top-cap and insert the locating pin.
Apply thumb pressure to hold the tappet in the maximum upward position.
Use torque wrench, Part No. 3376592, to tighten the adjusting screw to 0.6 to 0.7 Nm [5 to 6 in-lb].
Hold the adjusting screw and tighten the locknut to 61 Nm [45 ft-lb] without adapter or 47 Nm [35 ft-lb] with adapter ST-669.
Remove the tappet adjusting tool and check the injector push rod can be rotated by hand.
Adjust the valves on the appropriate cylinder with a feeler gauge per the sequence chart.
Tighten the valve adjusting screw and locknut, then check lash with a feeler gauge.
Install the cover, 16 isolators, spacers and capscrews; tighten to 15 Nm [130 in-lb].

P7 Axial Alignment Procedure adjustment

Check only when an objectionable vibration is present.
Remove the capscrews connecting drive discs and flywheel.
Mark the drive discs and flywheel with respect to each other.
Rotate engine or generator so drive discs holes are repositioned two bolt holes from original location.
Put capscrews back in and retorque. Recheck/record vibration levels.
Repeat this test until drive disc holes are repositioned 180 degrees from original location.
Review vibration data and position drive disc in lowest recorded level location.

UFRO Adjustments adjustment

⚠ Use an insulated handle screw driver to prevent electrical shock.

Tools: Insulated handle screwdriver, Frequency meter or tachometer

Make a note of the no-load frequency.
Determine roll-off frequency by turning the governor speed pot until the LED lights; if okay go to step 5.
Adjust the governor speed pot to the proper roll-off frequency.
Turn the UFRO pot until LED goes off, then slowly turn it back until the LED just goes on.
Adjust the governor speed pot back to the initial frequency setting.

Voltage and Voltage Stability Adjustments adjustment

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

Tools: Insulated handle screwdriver, AC voltmeter

Use the control panel mounted voltage trimmer, if provided, for small voltage adjustments.
Measure generator output voltage while running without load at nominal frequency.
If trimmer is insufficient, lock it at midpoint.
Turn the VOLTS pot fully counterclockwise and the STABILITY pot to its midpoint.
If the red LED lights, refer to Jumper Reconnections and UFRO Adjustments.
Turn the VOLTS pot clockwise until rated voltage is obtained.
If voltage becomes unstable with a large load, turn the STABILITY pot clockwise until stable.
Check and readjust the VOLTS pot each time the STABILITY pot is readjusted.

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.

Aftermarket parts that fit this engine

0327-1507 FridayParts $499.99 FP-XP-0041835

Parts listed by aftermarket suppliers as fitting this engine — leads compiled from supplier catalogs; verify the exact part for your serial number.

Common questions

What is the oil capacity of the Cummins/Onan M11?

The Cummins/Onan M11 engine has an oil capacity of 34.0 liters.

What is the displacement of the Cummins/Onan M11?

The Cummins/Onan M11 has a displacement of 10.8 liters with 6 cylinders.

Which generators use the Cummins/Onan M11 engine?

The Cummins/Onan M11 powers 4 generator set(s), including Cummins/Onan DQAA, Cummins/Onan DQAB, Cummins/Onan M1i Series Engines, Cummins/Onan ps200da.

How often should you change the oil in the Cummins/Onan M11?

The Cummins/Onan M11 oil change interval is every 6000 hours.

What is a common problem with the Cummins/Onan M11 engine?

A commonly reported issue on generators using the Cummins/Onan M11 is: Fuel Consumption — Excessive. Fix: Verify Complaint.