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Cummins/Onan QG 4000 Generator Set

The Cummins/Onan QG 4000 is a 4000 kW (4 kVA) gasoline standby generator set. It is available at 120 V, single-phase, 60 Hz and rated 33.3 A. The set measures 762×500.38×365.76 mm (30.0×19.7×14.4 in), weighs about 79.83 kg (176 lb) and produces 66 dBA at 3 m.

4000 kW
Standby
4
Document types

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

Compare with other 4000–4005 kW Gasoline generators →

Specifications

Fuelgasoline
Frequency60.0 Hz
Standby power4000 kW
Prime power4 kW
Voltage options120 V
Phase1
Rated current33.3 A
Power factor1
Battery voltage12 V
Battery quantity1
Max ambient500 °C
Dimensions (L×W×H)762×500×365 mm
Dry weight79 kg
Sound level66.0 dBA @ 3 m

Filters & service parts

model family
ItemSpecCapacityPart #Interval
Air filter—50 hr
Fuel filter—
Oil filter—
Battery—5000 hr
Belt—
Coolant—
Oil4.0 quarts—50 hr
Spark plug—

Compiled from this model's family documentation — may include parts for closely-related variants. Confirm the exact part for your serial number.

Service intervals

7
ItemActionHoursMonthsNotes
Oil levelCheck8 hrCheck oil daily or every 8 hours of operating time; perform a general inspection daily per Operator's Manual
Engine oilChange50 hrFirst service — Break-in: change engine oil after the first 20-50 hours of operation (RV QG/RV QG RM); perform at least once a year
Battery & connectionsClean1 moClean & check battery & connections; perform more often in hot weather
Oil/oil filter - Quiet Diesel 10000/12500ChangeFirst service — Break-in then repeat (footnotes 1-4, 2-4)
Oil/oil filter - Quiet Diesel 5500ChangeFirst service — Break-in then repeat (footnotes 1-4, 2-4)
Oil/oil filter - Quiet Diesel 7500/8000ChangeFirst service — Break-in then repeat (footnotes 1-4, 2-4)
Spark arresterClean1 moClean arrester; perform sooner if engine performance deteriorates

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

12
TypeItemValueUnitCondition
OtherEC-AGS+ gateway dimensions120 x 108 x 38mm
OtherPower output change with altitude3.5% decrease per 1000 ft increasetypical power output change based on ambient conditions
OtherPower output change with temperature1% decrease per 10 degF increasetypical power output change based on ambient conditions
OtherTemperature sensor dimensions51 x 70 x 17mm
ResistanceGateway harness continuity maximum resistance10Ohmsrepair or replace harness if greater
TemperatureAmbient conditions for rated power output77degFwith muffler and RV enclosure, per ISO 8528-1; altitude 500 ft (152.4 m), 99 kPa dry
TemperatureEC-AGS+ gateway operating temperature range-40 to 70°C
TemperatureTemperature sensor operating temperature range-40 to 85°C
VoltageEC-AGS+ nominal operating voltage12Vnominal
VoltageEC-AGS+ operating voltage range8 to 16VDC
VoltageMinimum house battery voltage for AGS use9VAGS not allowed below this
VoltageTemperature sensor battery replacement threshold2.5Vreplace when below

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

FluidGradeStandardAmbientCapacityNotes
Coolant50/50 ethylene glycol based antifreeze and waterMix thoroughly before adding; use clean soft tap water, distilled water or pure rain; select high quality antifreeze with corrosion inhibitors
Engine oilSAE 10W-30 / 10W-40 / 0W-30 / 5W-30Use viscosity chart to select grade for expected ambient temperature range; avoid mixing grades or brands
Engine oilSAE 15W-40API CF, CF-4, CG-4, CH-4, CI-4 or CJ-4 (diesel)OnaMax 15W-40 #326-5336; multi-grade recommended year-round in liquid-cooled engines; synthetic oil not recommended
Engine oilSAE-30API SJ, SL or SM (gasoline)OnaMax SAE-30 #326-5339; preferred summer grade for optimum oil consumption control in air-cooled engines
FuelASTM No.2-D / No.1-D / No.2-DLS / No.1-DLS / B5 Biodieselminimum Cetane number 45No.2-D or No.2-DLS above 23 degF; No.1-D or No.1-DLS below 23 degF; B5 Biodiesel above 50 degF; use No.1 diesel below 32 degF and during long light-load periods; cloud point at least 10 degF below lowest expected fuel temperature
FuelHD-5 grade liquid propaneat least 90% propaneFuels other than HD-5 can contain more than 2.5% butane causing poor vaporization/starting below 32 degF
FuelRegular unleaded gasolineEthanol blend not more than 10% ethanol; methanol blend not more than 5% methanolUse fresh gas, not more than 30 days old; fuel stabilizer extends fuel life
OtherCummins Onan Premium Fuel System Cleaner12.0 ozTreats up to 24 gallons of gasoline; #326-5342
OtherOnaFresh GXLP fuel stabilizer16.0 ozTreats 40 gallons of gasoline; #326-5365

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

Procedures

6
Installation and Setup Test diagnostic
  1. Verify generator set operation using the Start/Stop switch located on the generator set.
  2. Verify manual start/stop of the generator set from the app dashboard using the START and PRIME/STOP buttons.
  3. Check operation of the temperature sensors with Auto mode and Air Conditioning Sense enabled.
  4. Verify the generator set starts automatically when the settings are met.
  5. Verify the accelerometer by driving the vehicle at 10 mph and checking that AGS is automatically disabled.
  6. Verify delayed shutdown: enable AGS, allow the generator set to start, disable AGS, confirm shutdown in 10 minutes.
Connect Components (EC-AGS+ Gateway) installation

⚠ Accidental starting of the generator set can cause severe personal injury or death. Disconnect the starting (battery) cables before performing service.

⚠ Always disconnect a battery charger from its AC source before disconnecting the battery cables.

⚠ Seal all holes to prevent the entrance of exhaust gases into the vehicle interior.

  1. Plug the 12-pin connector from the harness to the EC-AGS+ gateway.
  2. Route the other end of the harness from the gateway to the Y-harness.
  3. For gas generator sets, plug the 8-pin EC-AGS+ harness connector into either lead of the Y-harness.
  4. For diesel generator sets, plug the 10-pin EC-AGS+ harness connector into the longer lead of the Y-harness.
  5. Connect the main lead of the Y-harness to the generator set.
  6. Connect the remaining Y-harness connector to the remote start/stop switch harness.
  7. Route the red wire lead to the positive terminal of the generator set starting battery and extend as necessary using butt connectors.
  8. Provide circuit protection by installing a 5 Amp fuse in the red wire lead.
  9. Locate the common ground location on the vehicle and route the black wire lead to the common ground.
  10. Route the grey wire lead to the engine battery positive terminal (optional connection).
  11. Insert battery ring terminal to the wires and connect the wires.
  12. Use cable ties at not less than 0.5 m (20 in) intervals to keep the wire bundle neat.
Connect Temperature Sensor(s) installation

Tools: Small flathead screwdriver

  1. Remove the lid from the sensor using a small flathead screwdriver.
  2. Remove the plastic battery tab from the sensor to enable the battery to provide power to the sensor.
  3. Place the lid back on the sensor.
Mount Components installation

⚠ High ambient temperature can cause damage to the EC-AGS+ gateway.

  1. Do not install the EC-AGS+ gateway directly inside the generator set compartment.
  2. Mount the EC-AGS+ gateway in a suitable, easily accessible location.
  3. Drill holes for the fastening screws and mount the EC-AGS+ gateway using mounting screws.
  4. Mount the temperature sensor(s) near an A/C thermostat (one per zone, 3 maximum).
  5. Drill 2 holes for screws and mount the sensor.
Temperature Sensor Battery Replacement maintenance

⚠ Pushing on the cover too hard can damage or break it.

Tools: Small flathead screwdriver

  1. Make sure the generator set is not set to start in Auto mode.
  2. Remove the top cover of the temperature sensor using a small flathead screwdriver.
  3. Slide the battery out of the battery holder and remove the battery.
  4. Slide the new battery into the battery holder and replace the cover.
Configure System Using App (Getting Started) operation

⚠ For first time set up or after factory reset, the vehicle must be kept stationary for at least 30 seconds to allow the gateway accelerometer to be configured properly.

  1. Download the EC-AGS+ app from the AppStore for iOS or Play Store for Android.
  2. Reconnect the generator set negative battery cable to power on the EC-AGS+ gateway.
  3. Verify that the EC-AGS+ gateway is powered by observing the LED blinking every 5 seconds.
  4. Turn on Bluetooth on the device containing the app.
  5. Select the EC-AGS+ App and select Start.
  6. Connect the gateway to the app via Discover EC-AGS+, Scan QR code, or gateway password.
  7. Read the End User License Agreement to the end and select Agree.
  8. Create a new password and select Assign Password.
  9. Select the generator set model and type; enter the Start Hours from the hour meter if available.
  10. Select Proceed to Dashboard.

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

Common questions

What is the power rating of the Cummins/Onan QG 4000?

The Cummins/Onan QG 4000 is rated 4000 kW standby.

What fuel does the Cummins/Onan QG 4000 use?

The Cummins/Onan QG 4000 runs on gasoline.

What is the continuous rating of the Cummins/Onan QG 4000?

The Cummins/Onan QG 4000 is rated 4 kW prime (4 kVA), against 4000 kW standby.

What is the sound level of the Cummins/Onan QG 4000?

The Cummins/Onan QG 4000 is rated at 66.0 dBA at 3 m, per the manufacturer specification sheet.

What is the dry weight of the Cummins/Onan QG 4000?

The Cummins/Onan QG 4000 has a dry weight of 79 kg (175 lb).

What voltage does the Cummins/Onan QG 4000 produce?

The Cummins/Onan QG 4000 is offered in 120 V, 1-phase.

How many cold cranking amps does the Cummins/Onan QG 4000 require?

The Cummins/Onan QG 4000 uses 1 battery, 12 V each, per the manufacturer specification sheet.

Troubleshooting

6

Symptoms & remedies

SymptomRemedy
Crank but won’t start1. Fuel below generator pickup level in tank. 2. Fuel supply shutoff valve closed. 3. Carbon deposits on spark plug(s). 4. Low oil level.
Exhausting black smoke1. Dirty air filter. 2. Choke stuck or misadjusted.
Unit runs then stops, or stops when driving around a corner1. Low fuel level. 2. Low oil level. 3. Excess oil.
Unit starts and runs, then stops when the start switch is released1. Low fluid levels. 2. Possible overheating. 3. Other functional problem.
Unit runs then surges1. Loose or worn spark plug leads. 2. Defective ignition coil, wiring, or control components. 3. Faulty spark plug. 4. Governor out of adjustment. 5. Combustion air pre-heat malfunction. 6. Carburetor icing. 7. Carburetor varnishing.
Circuit breaker trips1. Overloaded circuit.

Fault codes and symptom→remedy steps extracted from this model’s service/owner documentation; verify against the official manual before servicing. Full Cummins/Onan QG 4000 troubleshooting guide (14 entries) →

Parts

147model family
Part #DescriptionQtySystem
122-0645Filter, Oil1Oil filter Amazon eBay $11.99 NAPA $9.09
122-0645Cquartsc3.5Oil filter Amazon eBay
122-0800Oil filter1Oil filter Amazon eBay $31.23 FridayParts $39.99
122-0800Cquartsc3.5Oil filter Amazon eBay
122-0827Oil filterOil filter eBay $17.87 FridayParts $20.19
122-0833Filter, Oil1Oil filter Amazon eBay $19.99 NAPA $9.64 FridayParts $20.19
122-0836CAir FilterAir filter Amazon eBay
122-0893Oil filterOil filter eBay $49.99
140-0495Air Cleaner Element1Air filter Amazon eBay $16.99 NAPA $29.20
140-1220Air Cleaner ElementAir filter Amazon eBay $25.00
140-1229Air filterAir filter eBay
140-2105Oil filterOil filter eBay $44.01
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140-2379Element, Air Cleaner1Air filter Amazon eBay $11.59 NAPA $15.71
140-2379C140-2379cAir filter Amazon eBay
140-2379F140-2379cAir filter Amazon eBay
140-2609Oil filterOil filter eBay $9.99
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140-2842Air filterAir filter eBay
140-2897Element, Air Filter1Air filter Amazon eBay $19.99 FridayParts $48.61
140-2897IOil FilterOil filter Amazon eBay
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140-3280EOil FilterOil filter Amazon eBay
140-3295Oil filterOil filter eBay $12.79
140-3351Air filter1Air filter Amazon eBay $56.44
140-4151IOil Filter.11 quartsOil filter Amazon eBay
147-0860Filter, Fuel for HDKAK and HDKAH (Beginning Spec N)1Fuel filter Amazon eBay $19.99 KuduParts $12.00
147-0860ISpark PlugSpark plug Amazon eBay
148-0898Fuel filter1Fuel filter Amazon eBay
149-1353Filter, Fuel Pump Fuel1Fuel filter Amazon eBay $20.98 NAPA $7.27
149-1353GAir FilterAir filter Amazon eBay
149-1914-05Fuel Filter Element1Fuel filter Amazon eBay $41.25
149-2106Fuel Filter1Fuel filter Amazon eBay $34.99 NAPA $61.61 KuduParts $68.00
149-2137Air filter1Air filter Amazon eBay $37.20 KuduParts $7.00
149-2137HAir FilterAir filter Amazon eBay
149-2279Filter, Fuel1Fuel filter Amazon eBay $26.93 KuduParts $31.00 FridayParts $33.04
149-2279F149-2279FFuel filter Amazon eBay
149-2333Filter, Carburetor Fuel1Fuel filter Amazon eBay $10.97 KuduParts $8.00 FridayParts $10.50
149-2333ISpark PlugSpark plug Amazon eBay
149-2341Filter, Fuel1Fuel filter Amazon eBay $14.39
149-2457Air filterAir filter eBay $11.50 KuduParts $10.00 FridayParts $12.00
149-2457HAir FilterAir filter Amazon eBay
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149-2513Filter, Fuel1Fuel filter Amazon eBay $36.95 NAPA $31.59 FridayParts $48.61
149-2513IAir FilterAir filter Amazon eBay
149-2629Air filterAir filter eBay
149-2648Fuel filter (LP)Fuel filter eBay $20.00
149-2661IAir FilterAir filter Amazon eBay
149-2834IAir FilterAir filter Amazon eBay
160-1378Electronic IgnitionElectronic ignition Amazon eBay
167-0237Plug, Spark2Spark plug Amazon eBay $14.00 NAPA $3.97
167-0241Spark Plugs2Spark plug Amazon Amazon eBay $34.86 eBay $17.97
167-0241DSpark PlugSpark plug Amazon eBay
167-0247Spark Plug2Spark plug Amazon eBay $5.00
167-0262Spark plugSpark plug eBay $12.99
167-0263Spark Plugs2Spark plug Amazon eBay $19.00
167-0263-02Plug, Spark1Spark plug Amazon eBay $15.68 NAPA $2.23
167-0272Plug, Spark (E1, E2)2Spark plug Amazon eBay
167-0272BSpark PlugSpark plug Amazon eBay
167-0272CSpark PlugSpark plug Amazon eBay
167-0275Duct, Inlet-Air1Duct inlet air Amazon eBay $20.38
167-0275HSpark PlugSpark plug Amazon eBay
167-0298Plug, Spark2Spark plug Amazon eBay $9.99
167-0305Fuel filterFuel filter eBay
167-0305HSpark PlugSpark plug Amazon eBay
167-1602Cable, Spark Plug2Spark plug Amazon eBay $53.93
167-1638Fuel filterFuel filter eBay
167-1638HSpark PlugSpark plug Amazon eBay
167-1652ISpark PlugSpark plug Amazon eBay
185-2289Glow Plug (12 Volt)Glow plug Amazon eBay $24.95
185-5421Plug, Glow2Glow plug Amazon eBay $35.00
185-5835Oil Filter1Oil filter Amazon eBay $21.78 NAPA $3.59 FridayParts $20.19
185-5990Glow Plug (12 Volt)1Glow plug Amazon eBay $55.74
185-6623Glow plugGlow plug Amazon eBay $39.99
185-7444Filter, Oil1Oil filter Amazon eBay $29.95 NAPA $9.09 KuduParts $11.00 FridayParts $13.23
187-1000Filter, Oil1Oil filter Amazon eBay $63.20 FridayParts $20.19
187-1289Glow plug3Glow plug Amazon eBay
326-5336OnaMax engine oil, 15W-40, 32 oz. bottleFluid eBay $43.24
326-5339OnaMax engine oil, SAE-30, 32 oz. bottleFluid eBay $109.19
326-5365OnaFresh GXLP fuel stabilizer, 16 oz. bottleFluid eBay
333-080212V Glow PlugsGlow plug Amazon eBay $20.00
420-0577Oil filter wrench (cup-type)Oil filter Amazon eBay $19.68
A064X819Temperature Sensor1Sensor eBay
044-00087Y Harness - Other QG Generators1Service part / kit Amazon eBay
044-00135Y-Harness, Diesel1Service part / kit eBay
122-0645B122-0645BService part / kit Amazon eBay
122-0645D122-0645DService part / kit Amazon eBay
122-0645I122-0645IService part / kit Amazon eBay
122-0800B122-0800BService part / kit Amazon eBay
122-0827B122-0827BService part / kit Amazon eBay
122-0833C122-0833CService part / kit Amazon eBay
122-0836Tune-up kit (electronic ignition)Service part / kit eBay $18.99 FridayParts $20.28
122-0893E122-0893EService part / kit Amazon eBay
140-0495D140-0495DService part / kit Amazon eBay
140-1229D140-1229DService part / kit Amazon eBay
140-2609E140-2609EService part / kit Amazon eBay
140-2842I140-2842IService part / kit Amazon eBay
148-0898C148-0898CService part / kit Amazon eBay
148-0898I148-0898IService part / kit Amazon eBay
149-1353I149-1353IService part / kit Amazon eBay
149-191405EService part / kit Amazon eBay
149-2137I149-2137IService part / kit Amazon eBay
149-2279I149-2279IService part / kit Amazon eBay
160-0002Point Set, Breaker1Service part / kit Amazon eBay $19.99 NAPA $28.64
160-1154Point Set, Breaker1Service part / kit Amazon eBay
160-1328-01Tune-up kitService part / kit eBay
160-1348-01Tune-up kitService part / kit eBay
160-1349-01Tune-up kit (electronic ignition)Service part / kit eBay
167-0237B167-0237BService part / kit Amazon eBay
167-0237C167-0237CService part / kit Amazon eBay
167-0237D167-0237DService part / kit Amazon eBay
167-0247D167-0247DService part / kit Amazon eBay
167-0262B167-0262BService part / kit Amazon eBay
167-0262D167-0262DService part / kit Amazon eBay
167-0272D167-0272DService part / kit Amazon eBay
167-0272G167-0272GService part / kit Amazon eBay
167-0272I167-0272IService part / kit Amazon eBay
167-0275I167-0275IService part / kit Amazon eBay
167-0298B167-0298BService part / kit Amazon eBay
167-0298C167-0298CService part / kit Amazon eBay
167-0305I167-0305IService part / kit Amazon eBay
167-1615-01Cable, Spark Plug 9'1Service part / kit Amazon eBay
167-1616-01Plug wireService part / kit eBay $60.00
167-1625-01Plug wire, 9 in.Service part / kit Amazon eBay
167-1625-02Plug wire, 23 in.Service part / kit eBay
185-5835B185-5835BService part / kit Amazon eBay
185-5835C185-5835CService part / kit Amazon eBay
187-1000E187-1000EService part / kit Amazon eBay
286-6467)Service part / kit Amazon eBay
326-52784C Combustion Chamber and Carburetor Cleaner, 12-oz. aerosol canService part / kit eBay
326-5288Onagard storage fogging spray, 12-oz. aerosol canService part / kit eBay
326-5342Cummins Onan Premium Fuel System Cleaner, 12-oz. bottleService part / kit eBay
326-5366)Service part / kit Amazon eBay
525-030512 oz. Pressurized Spray Can1Service part / kit Amazon eBay
A064X814EC-AGS+ Gateway1Service part / kit eBay
A064X8155 Foot Harness, Gas1Service part / kit eBay
A064X8175 Foot Harness, Diesel1Service part / kit eBay
A065L01310 Foot Extended Harness, Gas1Service part / kit eBay $194.78
A065L01410 Foot Extended Harness, Diesel1Service part / kit eBay
EC-20Battery and Generator Monitoring System1Service part / kit Amazon eBay FridayParts $14.70 KuduParts $298.00
EC-30WWireless Autostart System1Service part / kit Amazon

Compiled from this model's family documentation — may include parts for closely-related variants. Confirm the exact part for your serial number. See the full parts catalog to search and cross-reference.

Fuel consumption

RatingLoadL/hgal/h
50%2.270.6
100%3.410.9

Available documents

Reference — 0043135 (Cummins/Onan)Reference — 0059498 (Cummins/Onan)Reference — F-1823-ENOwner's manual — 0056746 (Cummins/Onan)Owner's manual — F-1123-EN (Cummins/Onan)Owner's manual — Onan-EC-AGS Manual (Cummins/Onan)Parts manual — 0058449 (Cummins/Onan)Parts manual — F-1123 Cummins-Onan RV Generator Handbook (08-2007) (Cummins/Onan)Service manual — Cummins-Onan-RV-Generator-Handbook (Cummins/Onan)

This page was generated from the 9 manufacturer documents above by automated extraction; every figure shown is copied from one of them. How the data is compiled.