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Cummins/Onan WSG-1068 Engine

The Cummins/Onan WSG-1068 is a 6.8 L 10-cylinder naturally aspirated engine rated at 1800 rpm, producing up to 131.6 kW. It powers generator sets from Cummins/Onan, including the GGHE, GGHE-5778496, GGHF and GGHG. It holds 6.2 L (1.6 gal) of oil and 33.1 L (8.7 gal) of coolant.

Also known as: Onan Modified Ford V-10 WSG-1068

Part of the Cummins/Onan WSG1068 engine family — 3 variants share parts & fitment.

6.8 L

Displacement

Cylinders

1800 rpm

Rated speed

131 kW

Gross power

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

Engine specifications

Oil capacity	6.2 L
Coolant capacity	33.1 L
Displacement	6.8 L
Cylinders	10
Aspiration	Naturally Aspirated
Rated speed	1800 rpm
Gross power	131 kW

Generator sets powered by this engine

Cummins/Onan GGHECummins/Onan GGHE-5778496Cummins/Onan GGHF Cummins/Onan GGHG Cummins/Onan GGHH

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

Common problems

The engine does not crank in Run mode
Cause: The Emergency Stop switch has been used. (The switch button is lit.)
Fix: Pull the Emergency Switch button. To reset the engine control, push the Run-Stop-Remote switch to Stop and the Reset switch to Reset. Then push the Run-Stop-Remote switch to Run to start the genset.
The engine cranks but does not start
Cause: The engine is not getting fuel.
Fix: Open any closed fuel shutoff valve. (Valves closed for maintenance or new installations may require several crank cycles to get fuel to genset); Fill the propane supply tank; For natural gas fueled sets, check with the gas utility; Check fuel pressure at regulator (refer to Fuel Pressure in Section 6.) (High fuel pressure will prevent solenoid from opening); Check fuel solenoid (VDC present at K1+ lead during cranking); Duel Fuel Sets Only: Check relay K99. Refer to wiring diagrams in Section 7; Check pressure switch wiring. Propane − normally closed connected to common. Natural gas − normally open connected to common; Check pressure switch function (@ 3.5 inch H2O or less, should switch from natural gas to LPG); Check S14 vacuum switch (optional) for proper operation.
No output voltage
Cause: The line circuit breaker is OFF.
Fix: Find out why the circuit breaker was turned OFF, make sure it is safe to reconnect power, and then throw the circuit breaker ON.
The engine lacks power or is unstable
Cause: Current ambient conditions cause a derate, limiting power to less than rated power.
Fix: Determine proper derates for ambient conditions. Refer to specification sheet for site derating factors.
The field circuit breaker keeps tripping
Cause: The rotating rectifier assembly (diodes CR1 through CR6) is faulty
Fix: Shut down the set and check each diode according to Section 7; Service as necessary
The engine does not crank in Remote mode
Cause: The Run-Stop-Remote switch is at Stop. (The Switch-Off light will be flashing.)
Fix: Push the Run-Stop-Remote switch to Remote.
Output voltage is too high or too low
Cause: Engine speed is unstable
Fix: Troubleshoot according to the chart, The Engine Lacks Power or is Unstable
Engine will not crank.
Cause: Possible fault with control or starting system: Fault lamp on
Fix: Correct fault and reset control
The phase currents are unbalanced
Cause: The connected loads are distributed unevenly among the phases
Fix: Shut down the set and redistribute the loads as evenly as possible
Output voltage is unstable
Cause: The voltage has been adjusted improperly
Fix: Adjust output voltage according to Section 2, AC Control
The FAULT 1 or FAULT 2 fault lamp lights. Engine shuts down immediately, engine runs for several seconds and then shuts down, or engine continues to run. FAULT 1
Cause: The standard undesignated fault functions are programmed to shut down the set when a fault is sensed. Fault 1 is time delayed while Fault 2 is immediate. The nature of the fault is an optional selection that is determined when the set installation is designed. The undesignated fault functions may also be programmed for non-shutdown or non-time delay.
Fault lamp lights but no fault exists. Engine gauges show oil pressure, engine temperature, and frequency (speed) are within normal limits.
Cause: The monitor board or a sensor may be at fault
Fix: Contact an authorized service center for service
Battery completely discharged
Cause: Poor battery terminal connection
Fix: Clean connections, replace and tighten.
There is no remote circuit signal (12 VDC at auxiliary relay board A28-TB1-6) because fuse F3 on the ECM has blown. a
Fix: A. Replace the fuse with one of the same type and amp rating (15 A).<br>b. If fuse F3 blows again, find and repair the fault in the remote control circuit, such as a loose wire that may be shorting to ground or a shorted relay coil or other component. See Section 7 for remote connections.
There is no remote circuit signal (12 VDC at auxiliary relay board A28-TB1-6) because fuse F3 on the ECM has blown F3
Cause: Fuse F3 on the ECM has blown.
Fix: Replace the fuse with one of the same type and amp rating (15 A); If fuse F3 blows again, find and repair the fault in the remote control circuit, such as a loose wire that may be shorting to ground or a shorted relay coil or other component. See Section 7 for remote connections.

Compiled from service & troubleshooting documentation across every generator set that uses the Cummins/Onan WSG-1068.

Maintenance schedule

Item	Spec	Capacity	Part #	Interval
Air filter	Replace element every 2000 hours		—	2000 hr
Fuel filter			—
Oil filter			—	250 hr
Battery			416-0823	200 hr	Amazon
Belt	Spring-loaded idler maintains correct tension		—
Coolant		33.1 Gal (32.2 L)	—
Coolant filter			—
Oil		11.0 Qts (L)	—	250 hr
Spark plug			—	1000 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
Air cleaner	Check	100 hr		Replace as necessary; perform more often in extremely dusty conditions.
All exhaust components and hardware (fittings, clamps, fasteners)	Check	8 hr		Daily; audibly and visually with generator set running
All hardware (fittings, clamps, fasteners, etc.)	Check	100 hr	1 mo	Daily or after 8 hours.
Bedframe fluid containment (where fitted)	Drain	8 hr		Daily; drain if necessary
Coolant heater(s)	Check	24 hr		Standby power schedule. Daily or after 8 hours.
Coolant level	Check	24 hr		Standby power schedule. Daily or after 8 hours.
Coolant level of radiator(s) (water jacket & LTA)	Check	8 hr		Daily
Cooling fan blades	Check	8 hr		Visual inspection required daily
Drive belt condition and tension	Check	8 hr		Visually check belt for wear or slippage; replace if hard or brittle (Service Engineer)
Engine oil level	Check	24 hr		Standby power schedule. Daily or after 8 hours.
Fuel level in tank	Check	8 hr		Daily or after 8 hours
Fuel lines and hoses	Check	8 hr		Daily; check for oil, fuel, coolant and exhaust system leaks (Table 5 note 1)
General set	Inspect	8 hr		Check for oil, fuel, cooling and exhaust system leaks; inspect exhaust audibly/visually with set running and repair leaks immediately.
General set inspection	Inspect	8 hr		Daily/after 8 hours (X1). Check for oil, fuel, cooling and exhaust system leaks; check exhaust audibly and visually with set running.
Generator air outlet	Check	100 hr	1 mo	Standby power schedule. Daily or after 8 hours.
Generator set (general)	Inspect	24 hr		Standby power schedule. Daily or after 8 hours. Footnote 1: Check for oil, fuel, cooling and exhaust system leaks; check exhaust system audibly and visually with set running.
Crankcase oil	Change	50 hr		First service — Drain and replace crankcase oil after the first 50 hours of operation on new generator sets (break-in).
Crankcase oil	Drain	50 hr		First service — Drain and replace crankcase oil after first 50 hours of operation on new generator sets.
Engine oil and filter	Change	250 hr	6 mo	First service — Replace after the initial running-in period of 50 hours; contact your authorized distributor (Table 5 note 5)
Engine oil and filter	Drain	50 hr		First service — Break-in: drain and replace crankcase oil after first 50 hours of operation on new generator sets.
Air cleaner (heavy duty filter)	Check	100 hr		Prime power schedule. 100 hours. Footnote 2: Perform more often in extremely dusty conditions. Footnote 3: Replace element every 2000 hours.
Air cleaner (normal duty filter)	Check	100 hr		X2 perform more often in extremely dusty conditions; X3 replace element after 500 hours
Battery electrolyte level	Check	100 hr	1 mo	Standby power schedule. Monthly or after 100 hours.
Drive belt	Check	500 hr	12 mo	X5 visually check belt for evidence of wear or slippage; replace if hard or brittle
Governor linkage	Check	100 hr	1 mo	Perform more often in extremely dusty conditions.
Hardware (fittings, clamps, fasteners)	Check	100 hr		Standby power schedule. Monthly or after 100 hours.
All hardware (fittings, clamps, fasteners)	Check	250 hr	6 mo
Engine coolant port caps	Check	250 hr	6 mo	Replace after 4 years or 1000 hours.
Engine oil and filter (heavy duty filter)	Change	250 hr		Prime power schedule. 250 hours. Footnote 2: Perform more often in extremely dusty conditions.
Engine oil and filter (normal duty filter)	Change	250 hr	12 mo	X2 perform more often in extremely dusty conditions; X9 perform at least once a year
Exterior of radiator	Inspect	250 hr	6 mo	Inspect for obstructions.
Radiator exterior	Inspect	250 hr	6 mo	Inspect for obstructions.
Radiator hoses	Check	500 hr	12 mo	Check for wear and cracks; replace if hard or brittle.
Radiator hoses for wear and cracks	Check	250 hr	6 mo	Replace if hard or brittle.
AC generator and controls	Check	500 hr	12 mo	Yearly.
Anti-freeze	Check	500 hr	12 mo	Yearly.
Anti-freeze concentration	Check	500 hr	12 mo	Yearly or after 500 hours.
Catalytic converter restriction	Test	1000 hr	24 mo	X7 must be performed by a qualified mechanic; X8 replace every 8 years or 2000 hours
Cooling systems	Clean	500 hr	12 mo	Yearly.
Oxygen sensor	Inspect	1000 hr	24 mo	X6,7 inspect or replace; replace every 1,000 hours; must be performed by a qualified mechanic

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	Clearance around generator set for service	1	meter
Clearance	Exhaust pipe clearance to combustible wall or partition	305	mm
Clearance	Isolator base elevation tolerance between isolators	0.25	inch (6 mm)
Clearance	Vibration isolator top plate to base clearance	0.25	inch
Clearance	Vibration isolator top plate-to-base clearance (nominal)	0.25	inch (6 mm)
Gap	Spark Plug Gap	0.030	inch (0.762 mm)
Gap	Spark Plug Gap	0.044	in. (1.1 mm)
Gap	Spark plug gap	0.035	in (0.9 mm)
Gap	Spark plug gap	0.044 (1.1 mm)	in (mm)
Other	Adjust - Frequency Adjust range	5	% of nominal frequency
Other	Adjust - Voltage Adjust range	5	% of nominal voltage
Other	Air cleaner bench/paper element cleaning	Not recommended		Cummins Inc. does not recommend cleaning paper-type air cleaner elements
Other	B+ fused output	10	amps, 12/24 volt
Other	Battery charger output - 12 Volt	15	A
Other	Battery charger output - 24 Volt	12	A
Other	Battery charging alternator (max. rating)	37	A
Other	Battery electrolyte specific gravity (fully charged, corrected)	1.260	SG	at 25 °C (77 °F)
Other	Battery specific gravity (fully charged, corrected)	1.260		corrected by adding 0.004 per 10 F above 80 F (27 C)
Other	Battery specific gravity (recharge below)	1.215
Other	Battery specific gravity, charge required below	1.215	specific gravity
Other	Battery specific gravity, fully charged	1.260		corrected; add 0.004 per 10 F above 80 F (27 C)
Other	Battery specific gravity, fully charged (corrected)	1.260	specific gravity	corrected to 80°F (27°C)
Other	Battery specific gravity, recharge threshold	1.215		charge battery if reading is below this value
Other	Battery storage charging - further charge interval	6	months	at the normal initial charge rate until voltage ceases to rise
Other	Boost Charge interval (if charger fitted with Boost switch)	6	months	normally around every six months per battery manufacturer
Other	Charge battery if specific gravity below	1.215	SG
Other	Cool-down at idle time delay	0-30	minutes
Other	Cooldown at idle timer	0 - 30	minutes
Other	Customer Output relay rating (TB1)	2	amps at 30 VDC	normally open contacts
Other	Exhaust connection	3	inch NPT
Other	Frequency adjust range	+/-5	percent	nominal frequency
Other	Low Fuel warning (yellow lamp)	5	inches (127 mm) WC or less	dual or single fuel systems
Other	Metal surface cleaner	F4AZ-19A536-RA		Ford specification WSE-M5B292-A
Other	Output voltage adjustment range (voltage adjust rheostat, optional)	±5	% of nominal voltage
Other	Overcrank timed cranking period	approximately 75	seconds, including two rest periods
Other	Rated To Idle delay	0 - 10	seconds	default = 0; Beginning Version 2.303
Other	Rated to idle delay	0-10	seconds	default 0; beginning Version 2.303
Other	Relay contact rating (K10/K11/K12)	10	amps at 600 VAC
Other	Secondary regulator initial adjustment (distance from top of regulator to top of set screw), NG, 60 Hz	12.1	mm
Other	Secondary regulator initial adjustment, NG, 60 Hz	13.35	mm
Other	Secondary regulator initial adjustment, NG, 60 Hz	15.9	mm
Other	Silicone Gasket and Sealant	F6AZ-19562-A		Ford specification WSE-M4G323-A6
Other	Silicone gasket and sealant	F6AZ-19562-AA		Ford specification WSE-M4G323-A6; contact within 4 min, torque within 15 min
Other	Specific gravity temperature correction	0.007	SG per 10 °C (18 °F)	subtract above 25 °C (77 °F), add below
Other	Specific gravity, at end of charge, ambient frequently above 32 °C (90 °F)	1.240 - 1.260	SG
Other	Specific gravity, at end of charge, ambient normally below 32 °C (90 °F)	1.240	SG
Other	Specific gravity, electrolyte for filling new cells, ambient frequently above 32 °C (90 °F)	1.270 - 1.290	SG
Other	Specific gravity, electrolyte for filling new cells, ambient normally below 32 °C (90 °F)	1.270	SG
Other	Start Delay	0 - 300	seconds	default = 0
Other	Starting crank/rest cycle defaults	3 start cycles of 15 seconds cranking and 15 seconds rest (configurable 1-7)
Other	Starting cycles (crank/rest)	3	start cycles	default: 3 cycles composed of 15 seconds of cranking and 15 seconds of rest
Other	Stop Delay	0 - 600	seconds	default = 0
Other	Switched B+ fused output	5	amps, 12/24 volt	activated on run command
Other	Time Delay To Stop	0 - 600	seconds
Other	Time delay to start	0-300	seconds	default 0
Other	Time delay to stop	0-600	seconds	default 0
Other	Voltage adjust range	+/-5	percent	nominal voltage
Other	Warm-up at idle time delay	0 - 300	seconds
Other	Warm-up at idle time delay	0-300	seconds
Pressure	Concrete compressive strength for seismic anchors	4000	PSI

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% Ethylene Glycol and water	Fleetguard® Compleat ES low-silicate antifreeze, or equivalent			Standard concentration 50% Ethylene Glycol and water; must be maintained. Fill cooling system to the bottom of the fill neck in the radiator or expansion tank. Some radiators have two fill necks, both must be filled.
Coolant	50/50 coolant solution (50% pure water, 50% antifreeze)			32.2 L	Capacity with standard radiator 8.5 Gal (32.2 L). If temperatures below -37°F (-38°C) possible, use 65% antifreeze / 35% water. Do not use antifreeze with anti-leak additives. Use soft, low-mineral water.
Coolant	50/50 coolant solution (50% pure water, 50% antifreeze); 65% antifreeze/35% water if below -37°F (-38°C)			33.1 L	Cooling system capacity with standard radiator 8.8 Gal (33.1 L). Use clean, low-mineral soft water free of chloride, sulfate or acid. Do not use antifreeze containing anti-leak additives.
Coolant	50/50 water/antifreeze (65% antifreeze/35% water below -37F/-38C); no anti-leak additives		above -38°C	8.8 Gal (33.1 L)	Use soft water low in mineral content.
Coolant	50/50 coolant solution (50% pure water and 50% anti-freeze)		above -37°C	32.2 L	Cooling system capacity with standard radiator 8.5 Gal (32.2 L). If temperatures below -37 deg F (-38 deg C) are possible, use 65% antifreeze / 35% water. Do not use an antifreeze containing anti-leak additives. Use clean soft water low in mineral content.
Coolant	50/50 coolant solution (50% pure water and 50% antifreeze)	Do not use antifreeze containing anti-leak additives; use soft, low-mineral water	above -37°C	33.1 L	If temperatures below -37 F (-38 C) are possible use 65% antifreeze and 35% water. Cooling system capacity with standard radiator 8.8 Gal (33.1 L).
Engine oil	High-quality multi-viscosity lubricating oil such as Cummins Premium Blue® or its equivalent				Consult your authorized distributor for correct lubricating oil specifications for your operating conditions. Special running-in oils are not recommended.
Engine oil	Motorcraft Engine Oil XO-5W30-QSP	Ford specification WSS-M2C153-G			or equivalent
Engine oil	Refer to oil viscosity chart (Figure 5-1)	API SJ or SJ/CD		6.2 L	Select grade right for the lowest ambient temperature expected.
Engine oil	SAE 10W30, 5W30, 15W40	API classification SJ, SH or SL		6.2 L	Oil capacity with filters 6.5 Qts (6.2 L). Select viscosity grade for lowest expected temperature; if ambient is consistently below -13°F (-25°C), use a SAE 5W synthetic oil. Do not use oil that is too thick.
Engine oil	SAE 10W30, SAE 5W30, SAE 15W40	API classification SJ, SH or SL		6.2 L	Standby Power oil capacity 6.5 Qts (6.2 L) with normal oil filter; Prime Power 11 Qts (10.4 L) with heavy duty oil filter. If ambient temperature is consistently below -13 deg F (-25 deg C), use a SAE5W synthetic oil. Select grade for the lowest expected temperature.
Engine oil	SAE 5W synthetic (if ambient consistently below -13°F/-25°C)	API classification SJ or SJ/CD		6.2 L	Select viscosity grade per ambient temperature chart (Figure 5-1); oil capacity with filters 6.5 Qts (6.2 L).
Engine oil	Super Premium SAE 5W30 Motor Oil D9AZ-19579-A	Ford specification WSS-M2C153-G			or equivalent
Engine oil	API SJ, SH or SL; SAE 10W30, 5W30 or 15W40 per ambient temperature chart	API	above -25°C	6.5 Qts (6.2 L)	Use SAE5W synthetic oil if ambient temperature is consistently below -13F (-25C).
Engine oil	SAE 5W synthetic	API SJ or SJ/CD	above -25°C	6.2 L	Use SAE 5W synthetic if ambient temperature is consistently below -13 F (-25 C). Pick viscosity grade for lowest temperature expected. Oil capacity with filters 6.5 Qts (6.2 L).
Fuel	Natural Gas and/or Propane (LPG, liquid or vapor withdrawal)				Combination natural gas/LPG sets have separate shutoff solenoid valves and a fuel pressure switch for automatic changeover.
Fuel	Natural Gas and/or Propane (LPG, liquid or vapor)				Gaseous fuel; engine has a gas mixer serving both fuels with separate shutoff solenoid valves and pressure switch for automatic changeover.
Fuel	Natural Gas and/or Propane (Liquid or Vapor)				Fuel inlet pressure min 7.0 inch H2O NG/LPG; max 13.6 inch H2O NG/LPG vapor withdrawal, 312 psi LPG liquid withdrawal
Fuel	Propane (Liquid or Vapor); Natural Gas
Fuel	Propane (liquid or vapor) / Natural Gas				Fuel flow inlet pressure min 7.0 inch H2O (1.7 kPa) NG/LPG; max 13.6 inch H2O (3.4 kPa) NG/LPG vapor withdrawal; max 312 psi (2,153 kPa) LPG liquid withdrawal.

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
121	Speed Signal Lost	Category A	Shutdown
135	Oil Pressure Sensor H	Category C	Warning
141	Oil Pressure Sensor L	Category C	Warning
143	Pre-Low Oil Pres	Category D	Warning	If generator is powering critical loads and cannot be shut down, wait until next shutdown period and then follow code 415 procedure.
144	Coolant Sensor High	Category C	Warning
145	Coolant Sensor Low	Category C	Warning
146	Pre-High Coolant Temp	Category D	Warning	Reduce load if possible by turning off non-critical loads; check air inlets/outlets for obstructions. If engine can be stopped, follow code 151 procedure.
151	High Coolant Temp	Category D	Shutdown	Allow engine to cool. Check coolant level and leakage points, obstructions to cooling airflow, fan belt, blower fan/circulation pumps; reset control and restart.
197	Low Coolant Level	Category D (optional)	Warning	If generator is powering critical loads and cannot be shut down, wait until next shutdown period, then follow code 235 procedure.
234	Overspeed	Category A	Shutdown
235	Low Coolant Level	Category D (optional)	Shutdown	Allow engine to cool. Check coolant level and replenish, look for leakage points and repair; reset control and restart.
359	Fail To Start	Category D	Shutdown	Open any closed fuel shutoff valve; check for dirty/plugged air filter and replace if necessary; check gaseous fuel delivery; reset control and restart.
415	Low Oil Pressure	Category D	Shutdown	Check oil level, lines and filters; replenish oil if low; reset control and restart.
441	Low Bat Voltage	Category D	Warning	Check/recharge/replace discharged or defective battery; clean and tighten battery cable terminals; check battery charger float level.
442	High Bat Voltage	Category D	Warning	Check float level on battery charger if applicable (lower float level).
1123	Shutdown After BS	Category A	Shutdown
1124	Delayed Shutdown	Category E	Warning
1131	Battle Sh Active	Category E	Warning
1311	Customer Input #1	Category E		Programmable via InPower service tool: enable/disable, status (warning/shutdown/none), active open/closed, and display name.
1312	Customer Input #2	Category E		Programmable via InPower service tool: enable/disable, status (warning/shutdown/none), active open/closed, and display name.
1313-1316	Network Fault 1 thru 4	Category E
1317	Customer Input #3	Category E		Programmable via InPower service tool: enable/disable, status (warning/shutdown/none), active open/closed, and display name.
1318	Service Engine	Category B (begin spec J)	Warning	Indicates emissions criteria might not be met: engine running in open loop, lean mixture, rich mixture, or failed fuel system component.
1334	Crit Scaler OR	Category A	Shutdown
1335	Noncrit Scaler OR	Category B	Warning
1416	Fail To Shutdown	Category C	Warning
1417	Powr Down Error	Category D	Warning	Indicates controller cannot power down because of unknown condition; possible battery drain. Contact an authorized service center.
1433	Emergency Stop	Category D	Shutdown	Pull emergency stop button out; move O/Manual/Auto switch to O; press Fault Acknowledge/Reset button; select Manual or Auto as required.
1434	Remote E-Stop	Category D	Shutdown	See code 1433 to reset.
1435	Low Coolant Temp	Category D	Warning	Check coolant heater power connection/fuse; check for low coolant level and replenish, repairing leaks as needed.
1438	Fail To Crank	Category D	Shutdown	Possible fault with control, speed sensing or starting system. See code 441 for corrective action.
1442	Weak Battery	Category D	Warning	Battery voltage at/below weak-battery trip point during cranking. See code 441 for corrective action.
1443	Battery Failed	Category D	Shutdown	Dead battery, engine will not start. See code 441 for corrective action.
1444	KW Overload	Category B	Warning
1445	Short Circuit	Category A	Shutdown
1446	High AC Voltage	Category A	Shutdown
1447	Low AC Voltage	Category A	Shutdown
1448	Under Frequency	Category D	Shutdown	Check for dirty/plugged air filter and replace; check by disconnecting load and restarting; fuel system may require adjustment; check gaseous fuel delivery; reset and restart.
1449	Over Frequency	Category A	Warning
1452	Gen CB Not Close	Category A	Warning
1453	Gen CB Not Open	Category A	Warning
1459	Reverse Power	Category A	Shutdown
1461	Loss Of Field	Category A	Shutdown
1466	Modem Failure	Category C	Warning
1468	Network Error	Category C	Warning
1469	Speed/Hz Match	Category A	Shutdown
1471	Over Current	Category B	Warning
1472	Over Current	Category A	Shutdown
1477	Over Current	Over Current	Shutdown
2263	Battery Temperature	Battery temperature too high (reaches 55 °C [131 °F]) - battery charger fault message	Warning
2323-2326	Network Fault 5 thru 8	Category E
2327	PTC Fault	Category B	Warning
2329	Low S1 Frequency	Category E	Warning
2331	Low S1 Voltage	Category E	Warning
2335	Excitation Fault	Category A	Shutdown
2336	Memory Error	Category A	Shutdown
2337	Pwr Tran Disabled	Category C	Warning
2338	Pwr Tran Failure	Category C	Warning
2339	Pwr Down Enabled	Category E	Warning
2341	High Control Temp	Category B	Warning
2342	Too Long In Idle (10 min.)	Category E	Warning	Indicates genset has been in Idle mode too long (10 minutes maximum).
2358	High S1 Voltage	Category E	Warning
2396	S1 CB Not Close	Category E	Warning
2397	S1 CB Not Open	Category E	Warning
2966	PTC Timeout	Category C	Warning
2967	Governor Fault	Category C	Warning
2968	AVR Fault	Category C	Warning
2969	LON Failure	Category C	Warning
2972	Field Overload	Category A	Shutdown
Fault 1	Fault 1 (red)	Engine shut down because of a system fault; part of a 10-second time-delay shutdown circuit (customer-wired).	Shutdown
FAULT 1	FAULT 1	Red lamp indicates an undedicated fault; may be field programmed as shutdown or non-shutdown and as timed or non-timed (normally set for timed shutdown).	Shutdown	Nature of fault determined when set installation is designed.
Fault 2	Fault 2 (red)	Engine shut down because of a system fault; part of a non-time-delay shutdown circuit (customer-wired).	Shutdown
FAULT 2	FAULT 2	Red lamp indicates same features as Fault 1 (normally set for non-timed shutdown).	Shutdown	Nature of fault determined when set installation is designed.
HI ENG TEMP	HI ENG TEMP	Red lamp indicates engine has shut down because of critically high engine temperature (above 230 F / 110 C).	Shutdown	Allow engine to cool; check coolant level and airflow; reset control and restart.
High Engine Temperature	High Engine Temperature (red)	Engine shut down due to excessively high coolant temperature (greater than 230°F / 110°C).	Shutdown
LO FUEL	LO FUEL	Yellow (optional) lamp indicates fuel supply pressure is marginally low (5 inches [127 mm] WC or less).	Warning	Check for partially closed shutoff valve or empty propane supply tank; for natural gas check with the gas utility.
LO OIL PRES	LO OIL PRES	Red lamp indicates engine has shut down because of critically low oil pressure (below 25 psi / 172.4 kPa).	Shutdown	Check oil level, lines and filters; replenish if low; reset control and restart.
LOW ENG TEMP	LOW ENG TEMP	Yellow lamp lights if engine temperature is marginally low for starting (70 F / 21 C or lower); may indicate an inoperative coolant heater.	Warning	Check coolant heater operation, power supply, fuse/cord and coolant level.
Low Engine Temperature	Low Engine Temperature (yellow)	Engine temperature less than 65°F (18°C) or 90°F (32°C); possibility engine might not start.	Warning
Low Fuel	Low Fuel (yellow, optional)	Fuel supply pressure is 5 inches (127 mm) WC or less; also indicates operation on secondary fuel supply for dual-fuel sets.	Warning

Showing the first 80 of 93 codes.

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

Procedures

Adjusting Values/Parameters (Adjust Menu) adjustment

Tools: InPower Service Tool

Press the button next to the arrow symbol until the + and - symbols are displayed.
If necessary, press the button next to the symbols to move to the numeric character to change.
Press + to increase the value or select parameter; press - to decrease or select parameter.
Press the arrow symbol to save changes (cursor on last numeric character when adjusting values).

Gaseous Fuel Adjustments adjustment

⚠ Fuel is highly flammable; do not allow cigarettes, flame, pilot lights, arcing switches or equipment in area or areas sharing ventilation.

Tools: Exhaust gas analyzer (for emission sensitive areas)

Start the engine and let set warm up under partial load (at least 1/4 rated load); start with natural gas if dual fuel.
Connect full rated load and turn power adjust valve to full-rich.
Slowly turn adjust valve towards lean until engine begins to lose speed, then back towards rich until engine carries full load smoothly.
If equipped for natural gas and LPG, switch to LPG by closing manual shutoff valve in the natural gas supply line.
Reconnect full rated load and turn LPG flow adjustment valve clockwise until engine loses speed, then slowly back counterclockwise until engine carries full load smoothly.

Gaseous Fuel System Adjustment adjustment

⚠ Fuel is highly flammable and may cause severe personal injury and property damage. Do not allow cigarettes, flame, pilot lights, arcing switches or equipment in area or areas sharing ventilation.

Tools: Exhaust gas analyzer (for emission sensitive areas)

Start the engine and let the set warm up under a partial load (at least 1/4 rated load); on dual fuel sets start with natural gas.
Connect full rated load and turn the manual fuel valve two turns counterclockwise.
Slowly turn the manual fuel valve clockwise (lean) until the engine begins to lose speed.
Slowly turn it counterclockwise (rich) until the engine carries the full load smoothly.
On dual fuel sets, switch to LPG by closing the manual shutoff valve in the natural gas supply line.
Reconnect full rated load and turn the LPG flow adjustment valve clockwise until the engine begins to lose speed.
Slowly turn it back counterclockwise until the engine carries full load smoothly.

Gaseous Fuel System Adjustments adjustment

⚠ Fuel is highly flammable and may cause severe personal injury and property damage. Do not allow cigarettes, flame, pilot lights, arcing switches or equipment in area or areas sharing ventilation.

Tools: exhaust gas analyzer (for emission sensitive areas)

Start the engine and let the set warm up under a partial load (at least 1/4 rated load). Start with natural gas if dual fuel.
Connect full rated load and turn the power adjust valve two turns counterclockwise.
Slowly turn the manual fuel valve clockwise (lean) until the engine begins to lose speed.
Slowly turn counterclockwise (rich) until the engine carries full load smoothly.
If dual fuel, switch to LPG by closing the manual shutoff valve in the natural gas supply line.
Reconnect full rated load and turn the LPG flow adjustment valve clockwise until the engine begins to lose speed.
Slowly turn it back counterclockwise until the engine carries full load smoothly.

Magnetic Speed Pickup Unit Adjustment adjustment

Measure MPU resistance; replace if not between 1,000 and 1,050 ohms.
With MPU removed, rotate ring gear until a tooth lines up in the center of the mounting hole.
Thread pickup in gently by hand until it just touches the ring gear tooth.
Back the pickup out 1/4 turn and set the locknut.
Verify MPU output voltage at cranking speed is at least 1.5 VAC; replace MPU if less.

Output Voltage Adjustment adjustment

Adjust output voltage plus or minus five percent of nominal voltage using the Voltage Adjust rheostat (optional) on the control panel.
Call your distributor if the required voltage cannot be obtained by this adjustment.

Type A Gaseous Fuel Adjustment (Naturally Aspirated) adjustment

⚠ Gaseous fuels are flammable and explosive

Disconnect all loads, shut down set, and disconnect governor linkage at the carburetor.
Start engine and hold throttle closed by hand to prevent overspeed.
Adjust throttle idle position screw to obtain a frequency of 25-35 Hz.
Turn idle adjusting screw counterclockwise until engine becomes unstable, then clockwise to regain stability.
Reconnect governor linkage.
Connect full rated load and turn main fuel valve to full-rich, then lean until engine loses speed, then back to rich.
If equipped for LPG, switch to LPG and adjust LPG flow valve similarly under full load.

Vibration Isolator Installation and Adjustment Procedure adjustment

Place vibration isolators on the generator set support structure; shim or grout so all isolator bases are within 0.25 inch (6 mm) elevation of each other.
Loosen the side snubber lock nuts so the top plate is free to move vertically and horizontally; verify alignment with base and springs.
Place the generator set onto the isolators while aligning the skid mounting with the threaded isolator hole.
Adjust isolators with the leveling bolt to level the set; nominal clearance between top plate and base is 0.25 inch (6 mm) or greater.
If radiator and engine/alternator are mounted on separate skids, make both skids level for proper fan belt alignment.
If the set is not level, adjust leveling bolts until level with sufficient, roughly equal clearance on all isolators.
Lock the leveling bolt in place with the lock nut.
Leave snubber nuts loose to provide better isolation between the generator set and support structure.

Checking AC Electric System While Running diagnostic

⚠ High voltages are present inside the control box and generator output box when the set is running. Do not open the boxes while the set is running.

Check the frequency meter; generator frequency should be stable and match the nameplate rating.
Turn the phase selector switch to each line-to-line phase selection (L1-L2, L2-L3, L3-L1) and read the AC voltmeter; at no load voltage should match nameplate rating.
Turn the phase selector switch to each phase (L1, L2, L3) and read the AC ammeter; at no load current should be zero.
Push the Reset/Lamp switch; all indicator lamps should light, confirming all bulbs are on.
Have any burned out bulbs replaced.

Verify Overspeed Fault Detection diagnostic

Tools: special tool P/N 420-0604

For Type A sets, move the throttle lever/linkage to increase RPM to the overspeed shutdown range.
For Type B sets, remove the two screws securing the throttle body cover and remove cover.
Use special tool P/N 420-0604 to turn the end of the throttle shaft.
With genset operating at no load, slowly rotate the shaft clockwise until RPM reaches the overspeed limit and shuts down.
Replace the throttle body cover after completing the test.

AC Electrical Connections installation

⚠ Do not connect generator set directly to any building electrical system

⚠ Reconfiguring to different voltages can damage generator or windings; consult distributor

Place the control panel run switch in OFF position; remove AC power from battery charger; remove negative battery cable.
Install transfer switch for standby service applications.
Reconfigure generator output leads on connection terminal block per Reconnection Diagram as needed for nameplate voltage.
Bolt stranded load wires to the appropriate U/V/W/N terminals.
Balance loads so current flow from each line terminal is within 10 percent of median value.
Install current transformers (CT21/CT22/CT23) per Reconnection Diagram with dot facing toward the generator.
Ground the genset to earth in one location only.

AC Voltage Reconnection installation

⚠ Reconfiguring to higher voltages can exceed winding voltage capability and damage generator

⚠ Reconfiguring to lower voltages can increase line current beyond breaker rating

Check available generator output voltages and maximum current ratings on generator nameplate.
Reconfigure generator output leads per Reconnection Diagram on control housing side access cover if required.
Check stator lead terminal block connections and perform necessary reconnect to obtain required voltage.
Route current transformers (CT1, CT2, CT3) per Reconnection Diagram, dot facing generator, current flowing into dot.

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

Connection	Leads	Notes
Current Transformer routing: CT1-U load leads (A phase), CT2-V load leads (B phase), CT3-W load leads (C phase)	CT1, CT2, CT3	Dot on CT must face toward generator; dual secondaries post 2 (high voltage) or post 3 (low voltage)
Generator reconnection terminal block, terminals U/V/W/N correspond to L1/L2/L3/L0	U, V, W, N	Load balancing within 10 percent of median line current
Line 0 or Neutral	N / N / N	Load terminal line designations
Line 1	L1 / A / U	Load terminal line designations
Line 2	L2 / B / V	Load terminal line designations
Line 3	L3 / C / W	Load terminal line designations
TB1 Customer Faults	1=Customer Fault 1, 2=Ground Fault, 3=Low Fuel, 4=Rupture Basin Fault	Default settings, beginning spec J customer input #4 not available
TB1 Customer Relays	1=Common Warning, 2=Common Shutdown, 3=Not in Auto, 4=Ready to Load	Default settings; NO contacts rated 2 amps at 30 VDC
U, V, W, N terminals correspond to L1, L2, L3, L0	U=A phase (CT21), V=B phase (CT22), W=C phase (CT23)	Reconnection Diagram located on upper side cover of control housing

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 WSG1068 family

Part #	Description	Category
505-0091	Adapter, Carburetor	Adapter
140-3140	Air Cleaner - Top	Air filter
140-3146-01	Air Cleaner - Bottom	Air filter
140-3246	Gasket, Air Cleaner	Air filter
140-3265	Base, Mounting - Air Cleaner	Air filter
332-3561	Base, Mounting - Air Cleaner	Air filter
512-0252	Tensioner, Belt	Belt
140-3269	Breather, Air Cleaner	Breather
503-2296-01	Hose, Breather	Breather hose
307-2884	Elbow, Pipe	Elbow
148-1140	Carburetor (Includes Gaskets)	Gasket
800-3017-20	Harness, Wiring - Dual Fuel	Harness
503-1870-07	Clamp, Hose	Hose
503-2166	Hose, Breather	Hose
123-2185	Cap-Oil Fill	Oil filter
0123-2148	Indicator, Oil (Not Shown)	Oil indicator
104-1974	Bolt, Flywheel (M10 x 1.5 x 26.5)	Service part / kit
123-2147	Tube-Oil Level (Not Shown)	Service part / kit
123-2247	Valve-PCV (Low Flow)	Service part / kit
130-5256	Screw-Tensioner	Service part / kit
130-5257	Screw-Idler	Service part / kit
130-5386	Screw-Idler	Service part / kit
132-0331	Cap-Heater Tube (Not Shown)	Service part / kit
132-0412	Cap-Heater Tube (3/4) (Not Shown)	Service part / kit
140-3267	Box, Air - Adapter (Used on Generator Sets with F172 or F173 Enclosure)	Service part / kit
148-1090	Clamp, Fuel System - Input	Service part / kit
155-3719	Cover-Exhaust (Not Shown)	Service part / kit
332-1389	Tie, Cable	Service part / kit
505-0004	Nipple, Pipe (1.0 x 1.50)	Service part / kit
512-0250	Pulley (Smooth Idler)	Service part / kit
512-0251	Pulley (6 Groove Idler)	Service part / kit
517-0289	Plug, Hole	Service part / kit
520-1024	Stud (M6)	Service part / kit
520-1026	Stud-EXH Manifold	Service part / kit
525-0304	Gallon Can	Service part / kit
525-0305	12 oz. Pressurized Spray Can	Service part / kit
525-0306	Quart Can	Service part / kit
526-0018	Gasket, Flange (1-3/4)	Service part / kit
526-0174	Clamp, Muffler (1.50")	Service part / kit
526-2080	Washer, Flat (M6)	Service part / kit
526-2100	Washer, Flat (M8)	Service part / kit
800-2089	F lywhee 1 Screw, Cap - Hex !-lead (M1O X 45~) Grille, Air Outlet Screw, Socket Head (1/4-20 x 1/4')	Service part / kit
818-0237-01	Rivet, Pop (1/8)	Service part / kit
821-6003-02	Screw, Cap - Hex Head (M8 x 1.25 x 25mm)	Service part / kit
862-0001	Nut, Hex (1/4-20)	Service part / kit
865-0020	Nut, Wing	Service part / kit
928-0615C	Generator Set GGHG/GGHH	Service part / kit
928-0617	PowerCommand 2100 Controller	Service part / kit
F8JL-8A500-AA	5/8 inch cap, rear tube	Service part / kit
F8JL-8A500-BA	3/4 inch cap, front tube (if used)	Service part / kit
512-0211	Pulley-Water Pump	Pump
TB3-1	Terminal for relay K1 in the auxiliary relay board (ARB)	Relay terminal
TB4-5	Terminal for relay K2 in the auxiliary relay board (ARB)	Relay terminal
TB6-5	Terminal for relay K3 in the auxiliary relay board (ARB)	Relay terminal
193-0318	Sender, Water Temperature	Sensor
193-0551-01	Sensor-Map (Ignition)	Sensor
167-1639	Plug, Spark (Ford Part Number AGSF-22-FM1) (.035 Gap)	Spark plug
TB1-5	Charger AC Failure	Terminal block
130-5258	Thermostat (85°C) (Must Purchase F1VY-8255-A O-ring seal from Ford)	Thermostat

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 WSG-1068?

The Cummins/Onan WSG-1068 engine has an oil capacity of 6.2 liters.

What is the displacement of the Cummins/Onan WSG-1068?

The Cummins/Onan WSG-1068 has a displacement of 6.8 liters with 10 cylinders.

Which generators use the Cummins/Onan WSG-1068 engine?

The Cummins/Onan WSG-1068 powers 5 generator set(s), including Cummins/Onan GGHE, Cummins/Onan GGHE-5778496, Cummins/Onan GGHF, Cummins/Onan GGHG, Cummins/Onan GGHH.

How often should you change the oil in the Cummins/Onan WSG-1068?

The Cummins/Onan WSG-1068 oil change interval is every 250 hours.

What is a common problem with the Cummins/Onan WSG-1068 engine?

A commonly reported issue on generators using the Cummins/Onan WSG-1068 is: The engine does not crank in Run mode. Cause: The Emergency Stop switch has been used. (The switch button is lit.). Fix: Pull the Emergency Switch button. To reset the engine control, push the Run-Stop-Remote switch to Stop and the Reset switch to Reset. Then push the Run-Stop-Remote switch to Run to start the genset..