Service parts for the DQBB
Grouped by system, with how many of each the parts manual calls for.
Air intake
1 requiredFuel system
1 requiredOil system
1 requiredBelts
1 requiredPrices captured from merchant listings; some links are affiliate links. Confirm against your serial number before ordering.
Specifications
| Fuel | diesel |
|---|---|
| Frequency | 60.0 Hz |
| Standby power | 350 kW |
| Prime power | 315 kW |
| Controller | PowerCommand |
| Oil capacity | 34.0 L |
| Alternator | S-1154 |
| Voltage options | 480/277 V, 208/120 V, 240/120 V |
| Phase | 3 |
| Rated current | 12 A |
| Battery group | 8D |
| Battery cranking | 1400 CCA |
| Battery voltage | 12 V |
| Battery quantity | 2 |
| Coolant capacity | 51 L |
| Dimensions (L×W×H) | 5486×1676×2515 mm |
| Dry weight | 6532 kg |
| Sound level | 75.0 dBA @ 7 m |
| Fuel tank | 1040.0 L |
Engine
| Oil capacity | 34.0 L |
|---|---|
| Coolant capacity | 51.0 L |
| Displacement | 14.0 L |
| Aspiration | turbocharged |
| Rated speed | 1800 rpm |
Filters for the Cummins/Onan N14
6Engine-mounted filters the filter manufacturers list for this engine family. These come from the engine, not from this generator set’s own parts list, so confirm against your serial number before ordering.
| System | Filter | Description | Cross-references | |
|---|---|---|---|---|
| Oil filter | P553000 | Lube Filter, Spin-On Full Flow | CUMMINS 3318853, CUMMINS 3825970, NAPA 1748, NAPA 1748XD | FridayParts $125.00 |
| Oil filter | P550777 | Lube Filter, Spin-On Bypass | CUMMINS 3021658, CUMMINS 33004232, NAPA 1749, BALDWIN B7577 | FridayParts $43.56 |
| Fuel filter | P550105 | Fuel Filter, Spin-On Primary | CUMMINS 154700, CUMMINS 154710, NAPA 3109, NAPA 3405 | buy |
| Fuel / water separator | P558000 | Fuel Filter, Water Separator Spin-On Twist&Drain | CUMMINS 3308638, CUMMINS 3308683, NAPA 3405, NAPA 3693 | KuduParts $24.00 FridayParts $25.66 |
| Fuel / water separator | P551000 | Fuel Filter, Water Separator Spin-On Twist&Drain | CUMMINS 3161407, CUMMINS 3329289, NAPA 3406, BALDWIN BF1259 | FridayParts $99.00 |
| Coolant filter | P552071 | Coolant Filter, Spin-On Sca Plus | CUMMINS 299080, CUMMINS 299880, NAPA 4071, TORO 012706560 | FridayParts $37.53 |
Maintenance & consumables
for the Cummins/Onan N14| Item | Spec | Capacity | Part # | Interval | |
|---|---|---|---|---|---|
| Air filter | Air Compressor Air Cleaner Element - Two-Cylinder, Sponge Element | 256837 | Amazon eBay | ||
| Fuel filter | Fuel Shutoff Valve | 50121-43698 | Amazon eBay | ||
| Oil filter | 3375049 | 1500 hr | Amazon eBay | ||
| Battery | — | 1500 hr | |||
| Belt | Use on v-belts ( 3/8 to 7/8) and v-ribbed belts with 5 ribs or less. | 3822524 | Amazon eBay | ||
| Coolant | — | 6000 hr | |||
| Coolant filter | correct coolant filter determined by total cooling system capacity and oil drain interval | — | 250 hr | ||
| Oil | — | 6000 hr | |||
| Spark plug | — | 6000 hr |
Service intervals
2| Item | Action | Hours | Months | Notes |
|---|---|---|---|---|
| Crankcase oil and filter | Change | 250 hr | 12 mo | Table 7-1. If genset used for prime power, change every 6 months or 250 hours. If standby, change every 12 months or 250 hours, whichever comes first. |
| Rupture basin leak detect switch | Test | 12 mo | Check once a year; in some areas weekly inspections may be required by safety code regulations |
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
60| 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 | 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 |
| 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 | Engine oil pressure - K19 normal | 50-70 | psi (345-482 kPa) | run mode |
| Pressure | Engine oil pressure - K38 normal | 45-65 | psi (310-448 kPa) | run mode |
| Pressure | Engine oil pressure - K50 normal | 50-70 | psi (345-482 kPa) | run mode |
| Pressure | Engine oil pressure - L10/M11 normal | 30-50 | psi (207-345 kPa) | run mode |
| Pressure | Engine oil pressure - NTA 855 normal | 35-50 | psi (241-345 kPa) | run mode |
| Pressure | Engine oil pressure - V28 normal | 50-90 | psi (345-620 kPa) | run mode |
| Pressure | Engine oil pressure shutdown limit - L10/M11 | 20 | psi (138 kPa) | run mode value |
| Pressure | Engine oil pressure shutdown limit - L10/M11 | 8 | psi (55 kPa) | idle mode value |
| Pressure | Engine oil pressure warning limit - L10/M11 | 12 | psi (83 kPa) | idle mode value |
| Pressure | Engine oil pressure warning limit - L10/M11 | 25 | psi (172 kPa) | run mode value |
| Pressure | Idle oil pressure shutdown limit (PCC) | 12 | psi (83 kPa) | idle |
| Pressure | Idle oil pressure warning limit (PCC) | 15 | psi (104 kPa) | idle |
| Pressure | K19 engine idle oil pressure | 20 | psi (138 kPa) | idle |
| Pressure | K19 engine normal oil pressure | 50-70 | psi (345-482 kPa) | normal run |
| Pressure | K19 oil pressure shutdown/warning limits | shutdown 35 psi (241 kPa) run; warning 40 psi (276 kPa) run; shutdown 10 psi (69 kPa) idle; warning 15 psi (103 kPa) idle | psi (kPa) | |
| Pressure | K38 engine idle oil pressure | 20 | psi (138 kPa) | idle |
| Pressure | K38 engine normal oil pressure | 45-65 | psi (310-448 kPa) | normal run |
| Pressure | K38 oil pressure shutdown/warning limits | shutdown 35 psi (241 kPa) run; warning 40 psi (276 kPa) run; shutdown 10 psi (69 kPa) idle; warning 15 psi (103 kPa) idle | psi (kPa) | |
| Pressure | K50 engine idle oil pressure | 20 | psi (138 kPa) | idle |
| Pressure | K50 engine normal oil pressure | 50-70 | psi (345-482 kPa) | normal run |
| Pressure | K50 oil pressure shutdown/warning limits | shutdown 35 psi (241 kPa) run; warning 40 psi (276 kPa) run; shutdown 10 psi (69 kPa) idle; warning 15 psi (103 kPa) idle | psi (kPa) | |
| Pressure | L10/M11 engine idle oil pressure | 15 | psi (103 kPa) | idle |
| Pressure | L10/M11 engine normal oil pressure | 30-50 | psi (207-345 kPa) | normal run |
| Pressure | L10/M11 oil pressure shutdown limit | 20 | psi (138 kPa) | run mode value |
| Pressure | L10/M11 oil pressure shutdown limit | 8 | psi (55 kPa) | idle mode value |
| Pressure | L10/M11 oil pressure warning limit | 12 | psi (83 kPa) | idle mode value |
| Pressure | L10/M11 oil pressure warning limit | 25 | psi (172 kPa) | run mode value |
| Pressure | Low oil pressure service limit while cranking | 10 | psi | service lubricating system if below |
| Pressure | Low oil pressure shutdown (Detector) | 14 | psi (97 kPA) | |
| Pressure | Low oil pressure shutdown threshold | 14 | psi | less than this value shuts down |
| 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 | Normal engine oil pressure (PCC) | 35-50 | psi (242-345 kPa) | |
| 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 |
| Pressure | Oil pressure - NTA 855 engine idle | 15 | psi (103 kPa) | idle |
| Pressure | Oil pressure - NTA 855 engine normal | 35-50 | psi (241-345 kPa) | normal operating |
| Pressure | Oil pressure - V28 engine idle | 20 | psi (138 kPa) | idle |
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 | Refer to the Cummins engine Operation and Maintenance Manual for coolant recommendations/specifications | Balanced mixture of water, antifreeze and coolant additives. Drain and replace every year or after 500 hours whichever occurs first. | |||
| 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 | Refer to the Cummins engine Operation and Maintenance Manual for lubricating oil recommendations/specifications | Add oil of the same API viscosity and brand when necessary. Do not operate below low mark or above high mark. | |||
| Fuel | Diesel fuel | Do not use zinc coated or copper fuel lines with diesel fuel. Fuel connection at the engine should be made with an approved flexible line. | |||
| 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
53| Code | Name | Meaning | Severity | Action |
|---|---|---|---|---|
| 101 | IDLE MODE | Indicates that the engine is operating in idle mode. Grounding the engine idle input causes generator build-up to be inhibited and the engine to be governed at 800 RPM. | Warning | Remove ground from engine idle input to return to normal speed and voltage. |
| 102 | EMERGENCY STOP | Local or remote Emergency Stop. | 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 powering critical loads, wait until next shutdown period then follow 201 procedure. |
| 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; contact service center. |
| 204 | OIL PRES SENDER | Indicates that the control has sensed that the engine oil pressure sender is out of its working range. | Warning | Check that the engine oil pressure sender is properly connected. Contact service center. |
| 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; check air inlets/outlets and remove obstructions. |
| 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 | Contact an authorized service center. |
| 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 replenish; look for leaks and repair; reset and restart. Shutdown will not occur in Idle mode. |
| 220 | MAG PICKUP | Mag pickup speed indication not 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 | Contact an authorized service center. |
| 224 | FAIL TO SYNCHRONIZE | Generator set has not synchronized to the system bus within the allowable time frame. | Warning | Check governor system stability; adjust governing and synchronizer parameters; check fuel system. |
| 226 | FAIL TO CLOSE | Paralleling breaker has been given a signal to close, but has not closed properly. | Shutdown | Verify breaker charging mechanism; check close signal; verify auxiliary contact signals. |
| 230 | LOW DC VOLTAGE | Indicates battery voltage is below 10 VDC. | Warning | Recharge or replace the battery; check the battery charger fuse. Clean and tighten battery cable connections. Check engine DC alternator; replace if normal charging voltage is not obtained. Check float level if applicable. |
| 231 | HIGH DC VOLTAGE | Indicates battery voltage exceeds 32 VDC. | Warning | Lower battery charger float level if applicable; check engine DC alternator. |
| 232 | WEAK BATTERY | Indicates battery voltage drops below 60% of nominal for two seconds, during starting. | Warning | See Warning message 230, LOW DC VOLTAGE. |
| 240 | LOW FUEL−DAY | Indicates day tank fuel supply is running low. | Warning | Check fuel supply and replenish as required. |
| 241 | LOW FUEL | Low fuel signal received. | Warning | Check fuel supply and replenish; check for short to ground in external wiring. |
| 250 | EEPROM ERROR | PCC memory error; data corruption of critical operating parameters. | Shutdown | Perform 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 | Contact an authorized service center. |
| 313 | UNDER FREQUENCY | Indicates that engine speed has dropped below 90% of nominal for 10 seconds. Five seconds before shutdown, a Load Dump signal is initiated. | Shutdown | Contact an authorized service center. Load Dump signal initiated five seconds before shutdown. |
| 320 | OVERCURRENT | Indicates that generator output current has exceeded 110% of rated for 60 seconds. | Warning | Contact an authorized service center. |
| 321 | OVERCURRENT | Indicates that generator output current has exceeded 110% of rated, and that a PCC time/current calculation has initiated an overcurrent shutdown. | Shutdown | Contact an authorized service center. |
| 322 | SHORT CIRCUIT | Indicates that generator output current has exceeded 175% of rated. | Shutdown | Contact an authorized service center. |
| 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
12Aligning 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.
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.
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.
Generator/PCC Control Isolation Procedure diagnostic
⚠ HIGH VOLTAGE. Touching uninsulated high voltage parts inside the control box can result in severe personal injury or death.
Tools: Voltmeter, Jumpers, 12 volt battery
- Throw the line circuit breaker OFF and shut down the set.
- Remove accessory box cover; remove plug P10 from A37 J10.
- Prepare to measure output voltage across generator terminals.
- Connect 12V battery jumpers to X (P10-6 red) and XX (P10-3 brown).
- Check polarity; incorrect polarity makes the test inconclusive.
- Start set and connect battery negative to the XX lead.
- Rated or higher balanced voltage means generator circuitry is OK.
- Unbalanced voltage: troubleshoot main stator; low voltage: exciter/field.
Insulation Resistance (Megger) & Polarization Index (PI) Testing diagnostic
⚠ The windings of medium-voltage (601 through 15,000 volts) generator sets must be dry before the generator is operated.
Tools: Megger or insulation resistance meter, Grounding cluster, High voltage gloves
- Perform the Generator Set Grounding Procedure.
- Disconnect plug J10 from A37 and AC control leads 4,5,6,7,8.
- If RTD option installed, ground all six RTD temperature leads (18 leads).
- Perform Insulation Resistance Test and PI Test for desired windings.
- Megger test: apply voltage for up to one minute.
- PI test: apply voltage for ten minutes; record 1-minute and 10-minute readings.
- PI ratio of 2 or greater is good for new and in-service sets.
- Investigate and correct low readings before returning set to service.
Megger and PI Test diagnostic
⚠ Medium-voltage (601 to 15,000 volts) windings must be dry before the generator is operated.
Tools: Megger or Insulation Resistance Meter, Wheatstone bridge or digital ohmmeter, Grounding Cluster
- Perform the Generator Set Grounding Procedure.
- Disconnect plug J10 from the voltage regulator output module and the AC control leads (marked 4, 5, 6, 7, 8).
- If RTD option installed, ground all six RTD temperature leads (18 leads total).
- Perform the Winding Resistance Test for the desired windings.
- Perform the Insulation Resistance (Megger) Test and PI Test for the desired windings.
- Megger test: apply voltage for up to one minute.
- PI test: apply voltage for ten minutes; record resistance at one minute and ten minutes.
- PI is the ten-minute reading divided by the one-minute reading; ratio of two or greater is good.
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
| Voltage | 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.
Common questions
What size generator is the Cummins/Onan DQBB?
The Cummins/Onan DQBB is rated 350 kW standby.
Which engine powers the Cummins/Onan DQBB?
The Cummins/Onan DQBB is powered by the Cummins/Onan N14 engine.
What kind of fuel does the Cummins/Onan DQBB run on?
The Cummins/Onan DQBB runs on diesel.
How much oil does the Cummins/Onan DQBB take?
The Cummins/Onan N14 engine in the Cummins/Onan DQBB has an oil capacity of 34.0 liters.
What is the coolant capacity of the Cummins/Onan DQBB?
The Cummins/Onan DQBB cooling system holds 51 liters (13.5 US gallons) for the radiator system including the engine, per the manufacturer specification sheet.
What is the prime power rating of the Cummins/Onan DQBB?
The Cummins/Onan DQBB is rated 315 kW prime, against 350 kW standby.
How loud is the Cummins/Onan DQBB?
The Cummins/Onan DQBB is rated at 75.0 dBA at 7 m, per the manufacturer specification sheet.
What is the dry weight of the Cummins/Onan DQBB?
The Cummins/Onan DQBB has a dry weight of 6532 kg (14400 lb).
How big is the fuel tank on the Cummins/Onan DQBB?
The Cummins/Onan DQBB has a 1040 liter (275 US gallon) fuel tank.
What voltages is the Cummins/Onan DQBB available in?
The Cummins/Onan DQBB is offered in 480/277 V, 208/120 V, 240/120 V, 3-phase.
What battery does the Cummins/Onan DQBB use?
The Cummins/Onan DQBB uses 2 batteryies, 12 V each, 1400 CCA, group 8D, per the manufacturer specification sheet.
What alternator comes on the Cummins/Onan DQBB?
The Cummins/Onan DQBB uses a S-1154 alternator.
What oil filter fits the Cummins/Onan DQBB?
The Cummins/Onan DQBB uses oil filter part number 3375049.
What fuel filter does the Cummins/Onan DQBB use?
The Cummins/Onan DQBB uses fuel filter part number 50121-43698.
Which air filter part number does the Cummins/Onan DQBB take?
The Cummins/Onan DQBB uses air filter part number 256837.
Troubleshooting
6Fault codes
| Code | Meaning | Remedy |
|---|---|---|
| 231 | Warning lamp lights. | Indicates battery voltage exceeds 32 VDC. Contact an authorized service center. |
| 250 | Shutdown lamp lights. | Indicates PCC memory error. Data corruption of critical operating parameters. Contact an authorized service center. |
Symptoms & remedies
| Symptom | Cause | Remedy |
|---|---|---|
| Engine starts from generator control panel but will not start automatically or from a remote panel. | (Note: The Run/Off/Auto switch must be in the Auto position for automatic or remote starting). Check the control wiring between the remote switch and the PCC. Contact an authorized service center. | |
| No AC output voltage. | Contact an authorized service center. | |
| Control does not power up when the Run/Off/Auto switch is set to Run or the Self Test switch is pressed. | There is no DC power to the control. | A. Check for battery disconnected, discharged, or improperly connected. b. Fuse F1 (20A/32V, Type 3AG) may be open. Replace with the same type. (Fuse is mounted near engine starter/solenoid, see Figure 4-2). Contact an authorized service center. |
| Warning, Shutdown, and Non-Automatic lamps are not lit. Digital display shows main menu or selected menu. | Indicates all engine systems are normal. No corrective action required |
Fault codes and symptom→remedy steps extracted from this model’s service/owner documentation; verify against the official manual before servicing. Full Cummins/Onan DQBB troubleshooting guide (9 entries) →
Repair guides
6- Air Cleaner Service
- Crankcase Breather Service
- Emergency Stop Reset (PCC)
- Oil and Filter Change
- Resetting the Control (PCC)
- Starting at Control Panel (PCC)
Step-by-step procedures compiled from the Cummins/Onan service manual for this model.
Parts
114| Part # | Description | Qty | System | |
|---|---|---|---|---|
| 0300-4623-09 | DFCB (600V) | 1 | Current transformer | Amazon eBay |
| 0300-4623-10 | DFCC (600V) | 1 | Current transformer | Amazon eBay |
| 0300-4623-24 | DFCB BR (0-480V) | 1 | Current transformer | Amazon eBay $167.95 |
| 0300-4623-27 | DFCC BR (0-480V) | 1 | Current transformer | Amazon eBay |
| 08500039 | sea water pump screw | Screw | Amazon eBay | |
| 08600042 | sea water pump housing | Housing | Amazon eBay | |
| 08600043 | sea water pump gasket | Gasket | Amazon eBay | |
| 08600119 | sea water pump impeller | Impeller | Amazon eBay | |
| 19200074 | Buzzer | Engine harness adaptor cable | Amazon eBay | |
| 1920087 | Oil Pressure Sensor | Sensor | Amazon eBay | |
| 1920088 | Intake Manifold Pressure Sensor | Sensor | Amazon eBay | |
| 1920090 | ECM | ECM / ECU | Amazon eBay | |
| 1920096 | Fuel Pump Gear Pump | Fuel pump | Amazon eBay | |
| 1920097 | Oil Temperature Sensor | Sensor | Amazon eBay | |
| 1920098 | Engine Position Speed Sensor (behind lubricating oil pump) | Sensor | Amazon eBay | |
| 1920099 | Coolant Temperature Sensor (in thermostat housing) | Thermostat | Amazon eBay | |
| 1920100 | Coolant Level Sensor (in radiator) - Optional | Sensor | Amazon eBay | |
| 1920101 | Intake Manifold Temperature Sensor | Sensor | Amazon eBay | |
| 1920102 | Ambient Air Pressure Sensor (when required) | Sensor | Amazon eBay | |
| 19800109 | Engine Speed Sensor | Engine speed sensor | Amazon eBay | |
| 19801556 | ECM | ECM / ECU | Amazon eBay | |
| 19801560 | Fuel Block | Fuel block | Amazon eBay | |
| 19801564 | CENTRY™ STC Actuator Lead Wire | Electronic fuel control valve | Amazon eBay | |
| 19801565 | Fuel Pressure Sensing Line | Fuel pressure sensing line | Amazon eBay | |
| 19801567 | Main Engine Harness | Main engine harness | Amazon eBay | |
| 19801568 | Rail Pressure Sensor | Rail pressure sensor | Amazon eBay | |
| 256837 | Air Compressor Air Cleaner Element - Two-Cylinder, Sponge Element | 1 | Air filter | Amazon eBay |
| 3163196 | torque wrench adapter | Adapter | Amazon eBay | |
| 3318853 | Combination Full-Flow/Bypass Lubricating Oil Filter | 1 | Oil filter | Amazon eBay $74.95 NAPA $66.59 |
| 3822524 | Use on v-belts ( 3/8 to 7/8) and v-ribbed belts with 5 ribs or less. | 1 | Belt | Amazon eBay |
| 3822697 | Injector Puller | 1 | Injector | Amazon eBay |
| 3823348 | STC Injector Tappet Retaining Tool (IBC method) | Injector | Amazon eBay | |
| 3823579 | CELECT™ Injector Puller | 1 | Injector | Amazon eBay |
| 3824653 | STC Injector Puller | Injector | Amazon eBay | |
| 49200083 | ECM | ECM / ECU | Amazon eBay | |
| 50121-43698 | Fuel Shutoff Valve | 1 | Fuel filter | Amazon eBay |
| 50121-43700 | Thermostat | 1 | Thermostat | Amazon eBay |
| A40-TB1-2 | SWITCHED B+ | Belt | Amazon eBay | |
| A40-TB1-4 | GROUND | Belt | Amazon eBay | |
| A40-TB1-7 | COMMON ALARM | Belt | Amazon eBay | |
| A40-TB1-8 | JUMPER WIRE | Belt | Amazon eBay | |
| M-3034408 | Control Valve O-Ring | Seal | Amazon eBay | |
| M-3068959 | Barrel O-Ring | Seal | Amazon eBay | |
| M-3070113 | Injector Sleeve | Injector | Amazon eBay | |
| M-3070136 | O-Ring Seal Top | Seal | Amazon eBay | |
| M-3070137 | O-Ring Seal Middle | Seal | Amazon eBay | |
| M-3070138 | O-Ring Seal Bottom | Seal | Amazon eBay | |
| M-3072485 | Injector Plunger Link | Injector | Amazon eBay | |
| M-3075658 | Solenoid O-Ring | Seal | Amazon eBay | |
| M-3078226 | Injector Plunger Link | Injector | Amazon eBay | |
| M-3080421 | Sealing Washer | Seal | Amazon eBay | |
| 19100001 | Idle Shutdown Feature | Service part / kit | Amazon eBay | |
| 19100064 | Automotive Governor with Droop | Service part / kit | Amazon eBay | |
| 19160001 | Automotive Governor | Service part / kit | Amazon eBay | |
| 19200073 | WARNING and STOP lights in the cab panel | Service part / kit | Amazon eBay | |
| 19200075 | Maintenance monitor data (Cumulative Data, Trip Data, Idle Data, PTO Data) | Service part / kit | Amazon eBay | |
| 19200084 | Fan Clutch 2 Enable | Service part / kit | Amazon eBay | |
| 1920086 | Fuel Shutoff Valve | Service part / kit | Amazon eBay | |
| 1920089 | Cooling Plate | Service part / kit | Amazon eBay | |
| 1920091 | Engine Wiring Harness (actuator amp connector) | Service part / kit | Amazon eBay | |
| 1920092 | OEM Wiring Harness | Service part / kit | Amazon eBay | |
| 1920093 | Engine Mounted Service Tool Datalink | Service part / kit | Amazon eBay | |
| 1920094 | Fuel In | Service part / kit | Amazon eBay | |
| 1920095 | Fuel Out | Service part / kit | Amazon eBay | |
| 19400220 | Engine Brake Solenoid Valve | Service part / kit | Amazon eBay | |
| 19601595 | ADVANTAGE™ | Service part / kit | Amazon eBay | |
| 19801598 | ADVANTAGE™ POINT | Service part / kit | Amazon eBay | |
| 19801602 | Transient Black Smoke Control | Service part / kit | Amazon eBay | |
| 19801603 | CENTRY™ Plus | Service part / kit | Amazon eBay | |
| 19801610 | N14 Section 1 - Operating Instructions | Service part / kit | Amazon eBay | |
| 3376592 | Inch Pound Torque Wrench | 1 | Service part / kit | Amazon eBay $174.95 KuduParts $359.00 FridayParts $368.60 |
| 3823097 | High-temperature Anti-Seize Compound | 1 | Service part / kit | Amazon eBay |
| 3823461 | Chip Removal Tool | Service part / kit | Amazon eBay | |
| 49100029 | Fan Clutch 2 Enable | Service part / kit | Amazon eBay | |
| 49200053 | PTO Set | Service part / kit | Amazon eBay | |
| 49601601 | Torque Signal | Service part / kit | Amazon eBay | |
| 49801597 | Power Output | Service part / kit | Amazon eBay | |
| 49801599 | Low Speed High Speed | Service part / kit | Amazon eBay | |
| 49801603 | AFC CONTROLLED FUEL | Service part / kit | Amazon eBay | |
| C2800 | Fleetguard® refractometer | 1 | Service part / kit | Amazon eBay NAPA $393.59 |
| M-3066736 | Valve Spring Housing | Service part / kit | Amazon eBay | |
| M-3066738 | Valve Spring | Service part / kit | Amazon eBay | |
| M-3067426 | Valve Spring Retainer | Service part / kit | Amazon eBay | |
| M-3070184 | Cup Retainer | Service part / kit | Amazon eBay | |
| M-3071967 | Filter Screen | Service part / kit | Amazon eBay | |
| M-3072486 | Link Retainer | Service part / kit | Amazon eBay | |
| M-3072819 | – Spring Housing Spacer | Service part / kit | Amazon eBay | |
| M-3072821 | – Spring Guide | Service part / kit | Amazon eBay | |
| M-3072822 | – Socket Set Screw | Service part / kit | Amazon eBay | |
| M-3072823 | Spring Housing Spacer Assembly | Service part / kit | Amazon eBay | |
| M-3073244 | Cup Retainer | Service part / kit | Amazon eBay | |
| M-3075613 | Socket Head Cap Screw | Service part / kit | Amazon eBay | |
| M-3076068 | Ball Check | Service part / kit | Amazon eBay | |
| M-3076071 | Spray Tip Assembly | Service part / kit | Amazon eBay | |
| M-3076256 | Wiring Harness | Service part / kit | Amazon eBay | |
| M-3080766 | Coupling Retainer | Service part / kit | Amazon eBay | |
| M-3081342 | Plunger Coupling | Service part / kit | Amazon eBay | |
| M-3081371 | Upper Plunger Spring – Female | Service part / kit | Amazon eBay | |
| M-3081388 | Upper Plunger Spring – Male | Service part / kit | Amazon eBay | |
| M-3083863 | Plunger Coupling | Service part / kit | Amazon eBay | |
| M-3087552 | Upper Plunger – Male | Service part / kit | Amazon eBay | |
| M-3087791 | Spray Tip Assembly | Service part / kit | Amazon eBay | |
| M-3088175 | Spray Tip Assembly | Service part / kit | Amazon eBay | |
| M-3409978 | Spray Tip Assembly | Service part / kit | Amazon eBay | |
| M-3411340 | Plunger Coupling Spring | Service part / kit | Amazon eBay | |
| M-3411388 | Spray Tip Assembly | Service part / kit | Amazon eBay | |
| M-3411690 | Spray Tip Assembly | Service part / kit | Amazon eBay | |
| M-3411694 | Spray Tip Assembly | Service part / kit | Amazon eBay | |
| M-3411711 | Plunger and Barrel – Male | Service part / kit | Amazon eBay | |
| M-3411775 | Spring Retainer | Service part / kit | Amazon eBay | |
| M-3609852 | Spray Tip Assembly | Service part / kit | Amazon eBay | |
| M-3609855 | Spray Tip Assembly | Service part / kit | Amazon eBay | |
| M-3609861 | Spray Tip Assembly | Service part / kit | Amazon eBay | |
| M-3800419 | All manufacturer’s names, symbols and descriptions are used for reference only and it | Service part / kit | Amazon eBay |
Service, wear & replacement parts referenced for this model and its engine — confirm the exact part for your serial number. See the full parts catalog to search and cross-reference.
Fuel consumption
| Rating | Load | L/h | gal/h |
|---|---|---|---|
| Standby | 100% | 77.3 | 20.4 |
Available documents
Spec sheet — Cummins-installation-manual-DFAA-DFAB-DFAC-DFBC-DFBF-DFBD-DFBE-DFBF-DFCB-DFCC-DFCE-DFEB-DFEC-DFED-DFFA-DFFB-DFGA-DFGB-DFGC-DFJA-DFJB-DFJC-DFJD-DFLA-DFLB-DFLC-DFLD-DFLE-DFMB-DQAA-DQAB-DQBA-DQBB (Cummins/Onan)Spec sheet — s-1285 (Cummins/Onan)Operator's manual — 960-0101C Cummins DFBF DFCB DFCC DFCE DQBA DQBB Operators Manual (3-2001) (Cummins/Onan)Parts manual — 960-0268 Onan DQAA DQAB DQBA DQBB Parts Manual (9-1991) (Cummins/Onan)Service manual — 960-0507C Cummins DFAA thru DFMB DQAA Service Manual (2-2004) (Cummins/Onan)Service manual — 960-0619D Cummins DFA DFB DFC DFE DFF DFG DFJ DFL DFM DQA DQB Installation (6-2003) (Cummins/Onan)Service manual — Cummins-3100-PowerCommand-DFAA-DFAB-DFAC-DFBC-DFBD-DFBE-DFBF-DFCB-DFCC-DFCE-DFEB-DFEC-DFED-DFFA-DFFB-DFGA-DFGB-DFGC-DFJA-DFJB-DFJC-DFJD-DFLA-DFLB-DFLC-DFLD-DFLE-DFMB-DQAA-DQAB-DQBB (Cummins/Onan)Service manual — DFxx Generator Set Service Manual PCC3100 (Cummins/Onan)Service manual — Detector Control Generator Set Service Manual (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.