HomeEngines4B/6B/6C

4B/6B/6C Engine

The 4B/6B/6C is an engine. It powers generator sets from Cummins/Onan, including the DGBB, DGBC, DGCA and DGCC.

Also known as: 4B/6B/6C

Engine specifications

Common problems

15
  • Over Current 1471
  • Low Coolant Level 197
  • Weak Battery 1442
  • Under Frequency 1448
  • Too Long in Idle 2342
  • Speed/Hz Match 1469
  • Speed Signal Lost 121
  • Shutdown After Battle Short 1123
  • Short Circuit 1445
  • Remote Emergency Stop 1434
  • Pre-Low Oil Pressure Sensor 143
  • Pre-High Cool Temp 146
  • Power Down Failure 1417
  • Overspeed 234
  • Over Frequency 1449

Compiled from service & troubleshooting documentation across every generator set that uses the 4B/6B/6C.

Maintenance schedule

ItemSpecCapacityPart #Interval
Fuel filter500 hr
Oil filter250 hr
Battery
Belt
Coolant filter500 hr
Oil250 hr
Spark plug

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

Service intervals

40
ItemActionHoursMonthsNotes
Check Coolant LevelCheck8 hrDaily
Check Fuel LevelCheck8 hrDaily
Check Oil LevelCheck8 hrDaily
Coolant Level (Recovery Tank)Check8 hrTable 5-1
Coolant levelCheck8 hrDaily or after 8 hours
Drain Water from Fuel FilterDrain8 hrDaily; drain 1 cup or more of fuel to remove water and sediment.
Engine oil levelCheck8 hrDaily or after 8 hours
Fuel LevelCheck8 hrTable 5-1
Fuel Tanks (water and sediment)Drain8 hrDrain 1 cup or more of fuel to remove water and sediment.
General Genset InspectionInspect8 hrTable 5-1; also indicated for weekly/50 hours (X1, X2)
Inspect GensetCheck8 hrCheck for oil, fuel, cooling and exhaust system leaks. Check exhaust system audibly and visually with set running and repair any leaks immediately.
Inspect SetInspect8 hrDaily; check for oil, fuel, cooling, and exhaust system leaks.
Oil LevelCheck8 hrTable 5-1
Air CleanerClean50 hrTable 5-1; X3 perform more often in dusty conditions
Air cleaner (clean if required)Clean50 hrWeekly or after 50 hours; perform more often in dusty conditions
Battery charging systemCheck50 hrWeekly or after 50 hours
Charge Air PipingCheck50 hrTable 5-1
Check Anti-freeze and DCA ConcentrationCheck50 hrWeekly
Check Battery Charging SystemCheck50 hrWeekly
Check Battery Level and Specific GravityCheck50 hrWeekly
Check Coolant HeaterCheck50 hrWeekly
Check Drive Belt TensionCheck50 hrWeekly; visually check belts for evidence of slippage.
Check Generator Air OutletCheck50 hrWeekly
Coolant heaterCheck50 hrWeekly or after 50 hours
Crankcase OilDrain50 hrFirst service — Break-in: drain and replace the crankcase oil after the first 50 hours of operation on new generator sets.
Crankcase oilChange50 hrFirst service — Drain and replace after first 50 hours of operation on new generator sets.
Drain Exhaust Condensate TrapDrain50 hrWeekly
Drain Water and Sediment from Fuel TanksDrain50 hrWeekly; drain 1 cup or more.
Engine oil and filterChange50 hrFirst service — Drain and replace crankcase oil after first 50 hours on new generator sets
Exhaust condensate trapDrain50 hrWeekly or after 50 hours
Starting BatteriesCheck100 hrTable 5-1
Water and sediment from fuel tankDrain50 hrWeekly or after 50 hours; drain 1 cup or more of fuel to remove water and sediment
Check Air Cleaner (clean if required)Check100 hrMonthly; clean if required; perform more often in extremely dusty conditions.
Clean Generator AssemblyClean100 hrMonthly
Radiator hoses for wear and cracksInspect100 hrMonthly or after 100 hours
Battery Electrolyte LevelCheck200 hrCheck at least every 200 hours of operation; disregard for maintenance-free battery
Anti-freeze and DCA ConcentrationCheck250 hr6 moTable 5-1
Coolant FilterChange500 hr6 moTable 5-1
Cooling SystemClean500 hr6 moTable 5-1
Crankcase BreatherClean500 hr6 moTable 5-1

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
TypeItemValueUnitCondition
ClearanceClearance around generator set for maintenance and service access1meter (3 feet)
ClearanceExhaust pipe clearance from combustible wall or partition12inches (305 mm)minimum
ClearanceFloat switch lift below C-clip stop1/8inch (3 mm)
ClearanceFuel line clearance from electrical wiring1/2inch (12.7 mm)minimum
ClearanceFuel line clearance from hot exhaust parts2inch (51 mm)minimum
ClearanceOverspeed switch magnet-to-fly arm air gap (minimum)0.005inches (0.13 mm)
ClearanceVibration isolator base elevation (max difference between isolator bases)0.25inch (6 mm)
ClearanceVibration isolator top plate to base clearance0.25inch (6 mm)nominal, minimum
GapMechanical overspeed switch air gap between magnet and fly arm (replace switch if less)0.005inches (0.13 mm)
OtherAVR DROOP preset at factoryfive percent droop at full load and zero power factor
OtherBattery electrolyte corrected specific gravity (fully charged)1.260electrolyte temperature corrected
OtherBattery electrolyte specific gravity (fully charged)1.260specific gravitycorrected to 80 F (27 C)
OtherBattery electrolyte specific gravity charge threshold1.215specific gravitycharge battery if reading is below this value
OtherBattery electrolyte specific gravity, fully charged (corrected)1.260corrected to 80 °F (27 °C)
OtherBattery recharge threshold specific gravity1.215
OtherBattery specific gravity1.260at 77°F (25°C)
OtherBattery specific gravity recharge threshold1.260specific gravityrecharge if below
OtherBattery specific gravity temperature correctionfour gravity points (0.004) for every ten degrees above 80 F (27 C)
OtherBattery specific gravity, fully chargedapproximately 1.260at 80°F (27°C)
OtherCool-down at idle0−30min
OtherCoolant level50mmbelow radiator cap opening
OtherCoolant level below radiator cap opening2inches
OtherCustomer output relay contacts rating (TB1 outputs 1-4)2amps at 30 VDCnormally open contacts
OtherCycle crank crank and rest time7 to 20seconds
OtherCycle crank number of cycles3, 4, or 5
OtherCycle cranking (12-lamp control)3 cycles of 15 seconds
OtherCycle cranking option15seconds15 s crank, 15 s rest, 3 cycles
OtherDefault start cycles3cycles15 seconds of cranking and 15 seconds of rest
OtherECM fuse F1 (starter solenoid circuit)20amps
OtherECM fuse F2 (fuel solenoid circuit)20amps
OtherECM fuse F3 (continuous B+ to remote circuits)15amps
OtherECM fuse F4 (ECM circuits)5amps
OtherECM fuse F5 (engine gauge circuits)5amps
OtherFrequency adjustment range±5%%genset running
OtherFuse A31-F1 (control B+)5AmpEngine Interface board
OtherFuse A31-F3 (auxiliary B+)5AmpEngine Interface board; panel lights, run and start relays
OtherFuse A38-F1 (Network B+)10AmpGovernor Output Module
OtherFuse A38-F2 (Switched B+)10AmpGovernor Output Module
OtherFuse A38-F3 (Governor B+)10AmpGovernor Output Module
OtherFuse TB-Bat F1 (Customer B+)20AmpEngine Harness Assembly
OtherGOV RAMP adjustment range0 through 10seconds
OtherGovernor droop adjustment rangewithin 5percent of nominal frequency (3 Hz for 60Hz sets, 2.5 Hz for 50Hz sets)
OtherLow oil pressure / high engine temperature fault time delayabout 10secondsfollowing starter disconnect and inhibited during cranking
OtherMounting bolts used to secure vibration isolators to base5/8 inch or 16 mmanchored mounting bolts
OtherOptional control relay (K11, K12, K13) contacts rating10amps at 600 VAC
OtherOvercrank cranking limit75secondsstandard overcrank control
OtherOvercrank limit (Sentinel)60seconds
OtherOvercrank option limit (Detector)75seconds
OtherOvercrank time limit75seconds
OtherOverspeed warning range 60 Hz sets2000 to 2200RPM
OtherREG VHZ adjustment range1 through 50 (normal range 7 through 21)
OtherRandom voltage variation±1%for constant loads
OtherRated To Idle delay0−10secBeginning Version 2.303; default = 0
OtherResponse jumper setting - 90 to 550 kWB to C
OtherResponse jumper setting - over 550 kWA to B
OtherResponse jumper setting - under 90 kWA to C
OtherSetup/calibration menu access code574
OtherSpecific gravity correction factor0.004gravity pointsper 10 degrees electrolyte temperature above 80 F (27 C)
OtherStandard cycle cranking (Detector)three 15-second cranking cycles with two 15-second rest periods
OtherStart delay adjustment range0 to 300secondsremote starting in Auto mode

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
Coolantsoft water/E.G./DCA mixtureInstallation review checklist item: cooling system must be filled with soft water/E.G./DCA mixture.
Coolant50/50 mix of water and antifreezeBalanced coolant mixture of water, antifreeze and coolant additivesDrain and replace the mixture every 6 months or after 500 hours of operation. Do not add cold coolant to a hot engine; allow engine to cool below 120 F (50 C) before adding coolant.
CoolantWater/antifreeze mixturePermanent type antifreeze mixed per supplier for lowest expected ambient; do not use anti-leak additives
Engine oilRefer to Cummins engine Operation and Maintenance Manual for lubricating oil classificationGensets are shipped with oil added.
Engine oil5W (Synthetic Oil)API CC/CD, sulphated ash max 1.85%below -23°CBelow -10 F (-23 C) and below; pour point 9 F (5 C) below lowest expected temperature
Engine oilSAE 5W syntheticAPI CC/CD; sulphated ash max 1.85%; pour point 9°F (5°C) below lowest expected temperature; viscosity max 10,000 mPa·s at -31°F (-35°C) and min 4.1 mm²/s at 212°F (100°C)below -23°CFor ambient consistently below -10°F (-23°C) and no engine warm-up provision
Engine oil10W-30API CC/CD-23°C to -10°C-10 F (-23 C) to 14 F (-10 C)
Engine oil15W-40API CC/CDabove -10°C14 F (-10 C) and above
Engine oil20W-40API CC/CDabove 0°C32 F (0 C) and above
FuelASTM No. 2 diesel fuelCummins engines normally use ASTM No. 2 diesel fuel; will operate on alternate diesel fuels within specifications in Cummins engine Operation and Maintenance Manual.
FuelDieselDo not use zinc coated or copper fuel lines with diesel fuel.
FuelNo. 2 dieselNo. 1 fuel or similar acceptable; consult engine manufacturer for non-standard fuel
FueldieselDo not use zinc coated or copper fuel lines with diesel fuel.
Hydraulic oilDOT-3Trailer master cylinder reservoir - keep at least half full

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

80
CodeNameMeaningSeverityAction
101IDLE MODEIndicates that the engine is operating in idle mode; generator build-up is inhibited and engine governed at 800 RPM.WarningRemove ground from the engine idle input to return to normal speed and voltage.
102EMERGENCY STOPIndicates local or remote Emergency Stop.ShutdownPull the button out; move the Run/Off/Auto switch to Off; press the Reset switch; select Run or Auto as required. Can only be reset at the PCC front panel.
1122Rated/Idle TransRated/Idle transitionInfo
1123Shutdown After Battle ShortShutdown after Battle ShortShutdownReview Fault History and perform corrective action.
1124Delayed ShutdownDelayed shutdownWarningReview Fault History and perform corrective action.
1131Battle Sh ActiveControl is in Battle Short mode (bypasses several critical fault shutdowns).WarningWhen Battle Short mode is enabled, the Warning status indicator is lit along with displayed fault code 1131. Refer to Battle Short Mode description in Section 3.
121Speed Signal LostSpeed signal lostShutdownRestart and check RPM on digital display; inspect MPU wires/connector pins; check for 3.5 to 15 VAC at MPU while cranking.
1311Customer Input #1Customer input #1 (optional customer selection)WarningProgrammable (service tool): enable/disable input (default enable); status, warning or shutdown (default #1 = None); active closed or open (default closed [ground]); change display name up to 19 characters.
1311, 1312, 1317, 1318CUSTOMER INPUT #1 - #4Optional customer-selected fault input is active.Disconnect signal lead from TB1 and reset the control; check external wiring/active input selection.
1312Customer Input #2Customer input #2 (optional customer selection)WarningProgrammable (service tool): enable/disable input (default enable); status, warning or shutdown (default #2 = Warning); active closed or open (default closed [ground]); change display name.
1313−1316Network Fault 1 thru 4Network fault 1 through 4
1317Customer Input #3Customer input #3 (optional customer selection)WarningProgrammable (service tool): enable/disable input; status, warning or shutdown; active closed or open; change display name.
1318Customer Input #4Customer input #4 (optional customer selection)WarningProgrammable (service tool): enable/disable input; status, warning or shutdown; active closed or open; change display name.
1334Crit Scaler Out Of RangeIncorrect feature or calibration was entered into control.ShutdownReload correct feature/calibration file.
1335Noncrit Scaler Out Of RangeNon-critical scaler out of rangeWarningReload correct feature/calibration file.
1337No MessageNo messageInfo
135Oil Pressure Sensor HOil pressure sensor highWarningCheck sender/connectors/wires; verify fault simulation not enabled; check 0.5 to 4.5 VDC at P7-13 (OP OUT) and P7-17 (OP COM).
141Oil Pressure Sensor LOil pressure sensor lowWarningCheck sender/connectors/wires; check for shorts/open circuits at P7-13, 17, 21.
1416Fail To ShutdownGenset continues to run after receiving shutdown command (Battle Short feature enabled).WarningRefer to Battle Short Mode description in Section 3.
1417Powr Down ErrorThe controller cannot power down because of some unknown condition; possible drain on batteryWarningIndicates controller cannot power down because of unknown condition. Possible drain on battery. Contact an authorized service center for service.
143Pre-Low Oil PresEngine oil pressure has dropped below the warning trip pointWarningIndicates engine oil pressure has dropped below the warning trip point. If generator is powering critical loads and cannot be shut down, wait until next shutdown period and then follow code 415 procedure.
1433Emergency StopLocal Emergency Stop.ShutdownPull the button out; move switch to O; press Fault Acknowledge/Reset; select Manual or Auto.
1434Remote E-StopRemote Emergency Stop.ShutdownSee code 1433 to reset.
1435Low Coolant TempInitiates a warning when the engine jacket water coolant temperature falls below 70 deg F (21 deg C); provided to meet NFPA 110 requirements, in conjunction with illumination of the Warning LED.WarningIndicates engine coolant heater is not operating or is not circulating coolant. Check coolant heater power supply for blown fuse or disconnected cord; check for low coolant level and replenish; look for coolant leaks and repair.
1438Fail To CrankPossible fault with control, speed sensing or starting systemShutdownTest for B+ at the starter; check fuse F3 (2 Amps); check K4 start pilot relay and starter circuitry; refer to code 121.
144Coolant Sensor HighEngine coolant temperature signal is shorted high.WarningCheck sender/connectors/wires; check resistance between P7-30 (IH20) and P7-34 (IH20 COM).
1442Weak BatteryDuring cranking, battery voltage is at or below the weak battery warning trip point for a time greater than or equal to the weak battery set timeWarningSee code 441 for corrective action.
1443Battery FailedDead battery − engine will not startShutdownSee code 441 for corrective action.
1444KW OverloadkW overloadWarningCheck load and load lead connections; check CTs and CT connections.
1445Short CircuitShort circuitShutdownCheck load and load lead connections (fault may not reset for several minutes).
1446High AC VoltagePhase voltage exceeded 130% of nominal, or 110% of nominal for 10 seconds.ShutdownCheck fault simulation; clear fault and restart; refer to Generator/Base Board Isolation Procedure.
1447Low AC VoltagePhase voltage dropped below 85% of nominal for 10 seconds.ShutdownCheck load; reconnect per reconnection diagram; check PMG/field wiring; check P8-21/P8-22 shunt connections.
1448Under FrequencyUnder frequencyShutdownCheck fuel supply, intake air supply and load; check P8 connections.
1449Over FrequencyOver frequencyWarningCheck fuel or air delivery problem; repair P7/P8 connections.
145Coolant Sensor LowEngine coolant temperature signal is shorted low.WarningCheck sender/connectors/wires; check for shorts at P7-30 and P7-34.
1452Gen CB Not CloseGenset circuit breaker (S2) failed to close when PTC enabled.WarningRefer to Section 5.
1453Gen CB Not OpenGenset circuit breaker (S2) failed to open when PTC enabled.WarningRefer to Section 5.
1459Reverse PowerReverse powerShutdownCheck wiring to voltage sense circuit; refer to CT Installation in Section 6.
146Pre-High Coolant TempEngine is operating near cooling system capacityWarningReduce load; check air inlets/outlets and remove obstructions to airflow; if engine can be stopped follow code 151.
1461Loss Of FieldLoss of field (electric) due to reverse kVAR.ShutdownCheck field circuit.
1466Modem FailureModem failureWarningCheck for open, short circuit to ground, and loose connections to the modem.
1468Network ErrorNetwork errorWarningRefer to the LonWorks Network publications.
1469Speed/Hz MatchSpeed/Hz matchShutdownCheck calibration file.
1471Over CurrentOver currentWarningCheck load and load lead connections.
1472Over CurrentOver currentShutdownCheck load and load lead connections (fault may not reset for several minutes).
151High Coolant TempEngine has overheated (coolant temperature has risen above the shutdown trip point)ShutdownEngine has overheated. Allow engine to cool completely, then: check coolant level and replenish and repair leaks; check for obstructions to cooling airflow; check fan belt and repair or tighten; check blower fan and circulation pumps on remote radiator installations; reset control and restart.
197Low Coolant LevelEngine coolant level has fallen below the warning trip point.WarningIndicates engine coolant level has fallen below warning trip point. If generator is powering critical loads and cannot be shut down, wait until next shutdown period, then follow code 235 procedure. If engine can be stopped, follow code 235 procedure.
200LOW OIL PRESSUREIndicates engine oil pressure has dropped to an unacceptable level.WarningIf powering critical loads, wait until next shutdown period and follow 201-SHUTDOWN procedure; check oil pressure via menu prior to clearing fault.
201LOW OIL PRESSUREIndicates engine oil pressure has dropped below the shutdown trip point.ShutdownCheck oil level, lines and filters; replenish if low; reset control and restart. Oil pressure limits in Table 4-3.
204OIL PRESS SENDERThe control has sensed that the engine oil pressure sender is out of its working range.WarningCheck that the engine oil pressure sender is properly connected.
210LOW COOLANT TEMPWarning occurs when engine coolant temperature is 70°F (21°C) or lower, indicating the engine coolant heater is not operating or is not circulating coolant.WarningIndicates engine coolant heater is not operating or is not circulating coolant; check coolant heater power supply/fuse, low coolant level, and open heater element.
211HIGH COOLANT TEMPIndicates the engine coolant temperature is getting close to the recommended maximum temperature limit: 215°F (102°C) standby or 207°F (97°C) prime.WarningReduce load if possible; check air inlets/outlets; follow 212-SHUTDOWN procedure if engine can be stopped.
212Oil Temp Sensor HOil temperature sensor highWarningCheck sender/connectors/wires; check resistance between P7-22 (OIL TEMP) and P7-26 (OIL TEMP COM).
213Oil Temp Sensor LResistance of the coolant temperature sender is out of range.WarningCheck the resistance of the sender; should be 500 to 2k ohms.
214LOW COOLANT LVLIndicates engine coolant level has fallen below the trip point.WarningCheck coolant level in radiator and coolant recovery bottle; look for leakage; reset control and restart.
215LOW COOLANT LVLIndicates engine coolant level has fallen below the trip point. LOW COOLANT LVL Shutdown will not occur if genset is in Idle mode (low coolant warning only).ShutdownCheck coolant level in radiator and recovery bottle and replenish if low; check defective coolant bottle hose or radiator cap; reset control and restart after correcting problem. Will not occur in Idle mode.
220MAG PICKUPMag pickup speed indication is not being sensed or does not match generator set output frequency.ShutdownRestart and check RPM on the digital display; isolate per troubleshooting table 4-18.
221FAIL TO CRANKPossible fault with control or starting system; engine will not crank.ShutdownCheck fuse F3 on the Engine Interface board; clean battery cable connections; recharge or replace battery.
222OVERCRANKPossible fuel system problem; engine stops cranking.ShutdownCheck for empty fuel tank, fuel leaks, or plugged fuel lines; check/replace dirty fuel filter and air filter; reset and restart.
223OVERSPEEDIndicates engine has exceeded normal operating speed (115% ±1% of nominal).ShutdownInspect the mechanical fuel linkage and repair or replace; check the EFC for binding or damage; monitor the PCC duty cycle display and replace A32 or A38 as indicated.
224FAIL TO SYNCHRONIZEThe generator set has not synchronized to the system bus within the allowable time frame.Check governor system stability and adjust governing/synchronizer parameters; check for fuel system problems causing engine instability; widen synchronizing window and reduce acceptance time delay.
226FAIL TO CLOSEIndicates that the paralleling breaker has been given a signal to close, but has not closed properly.Verify charging mechanism of paralleling breaker; check the close signal to the breaker; verify auxiliary contact signals from the breaker to the control are operational.
230LOW DC VOLTAGEIndicates battery voltage is below 10 VDC.WarningRecharge or replace battery; clean/tighten connections; check engine DC alternator; check battery charger float level.
231HIGH DC VOLTAGEIndicates battery voltage exceeds 32 VDC.WarningCheck voltage float level on battery charger if applicable (lower float level); check engine DC alternator and replace if normal battery charging voltage is not obtained.
232WEAK BATTERYIndicates battery voltage drops below 60% of nominal for two seconds, during starting.WarningRecharge or replace the battery; see 230 LOW DC VOLTAGE.
2323−2326Network Fault 5 thru 8Network fault 5 through 8
2327PTC FaultPTC module or communication link not working properly when PTC enabled.WarningCheck blinking light on PTC module; check B+ TB3-3 to TB3-4; check PTC status voltage TB3-5 to TB3-6 (~0.2 VDC); repower control.
2329Low S1 FrequencyLow utility (S1) frequency.WarningCheck S1 AC inputs and wiring to PTC at TB5; check sensor set points.
2331Low S1 VoltageLow utility (S1) voltage.WarningRepower PCC 2100 control to clear; check S1 AC inputs at TB5; check S1 pickup/dropout set points.
2335Excitation FaultLoss of all three voltage sense leads or failure in excitation circuit.ShutdownCritical shutdown fault; suspends Battle Short and shuts down immediately.
2336Memory ErrorMemory errorShutdownTry reloading calibration file.
2337Pwr Tran DisabledPower transfer disabledWarningUse InPower to enable PTC feature; cycle power off for 5 seconds then repower.
2338Pwr Tran FailurePower transfer failureWarningCheck blinking light and B+ TB3-3 to TB3-4; check connections between TB2 and TB3; cycle power.
2339Pwr Down EnabledPower down enabledWarningNone required.
234OverspeedOverspeed shutdownShutdownCritical shutdown fault; suspends Battle Short and shuts down immediately.
2341High Control TempHigh control temperatureWarningCheck genset room air flow.
2342Too Long In Idle (10 min.)Genset has been in Idle mode too long.WarningIndicates genset has been in Idle mode too long (10 minutes maximum).
235Low Coolant LevelEngine coolant level has fallen below the shutdown trip point.ShutdownCoolant level has fallen below the shutdown trip point. Allow engine to cool completely, then check coolant level and replenish, look for possible coolant leakage points and repair; reset control and restart.
2358High S1 VoltageUtility (S1) voltage increased above over voltage threshold.WarningMeasure S1 AC inputs at PTC module; check utility nominal voltage; check sensor set points.
2396S1 CB Not CloseUtility contact (S1) failed to close with PTC enabled.WarningRefer to Section 5.

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

Procedures

12
Adjusting Default Settings (Controller Configuration Menu) adjustment
  1. Make sure Main Menu 1 is displayed and simultaneously press the Home Menu and Previous Main Menu buttons.
  2. Press the buttons next to the and symbols to navigate between the three submenus.
  3. Press the button next to the symbol until the + and − symbols are displayed.
  4. Press the button next to the + or − symbol to select the desired option.
  5. Press the symbol to save the changes.
Adjusting Values/Parameters adjustment

⚠ If Home button or Previous Main Menu button is pressed before pressing save symbol, changes are not saved.

  1. Press button next to symbol in display until + and − symbols are displayed.
  2. Press button next to arrow symbols to move to numeric character to change.
  3. Press button next to + symbol to increase value or select parameter.
  4. Press button next to − symbol to decrease value or select parameter.
  5. After adjusting values/selecting parameters, press symbol to save changes.
Adjusting Values/Parameters (Adjust Menu) adjustment

⚠ If the Home button or Previous Main Menu button is pressed before pressing the save symbol, the changes are not saved.

⚠ Long periods of engine idling can eventually affect engine performance and may void engine warranty.

  1. Press the button next to the symbol in the display until the + and − symbols are displayed.
  2. If necessary, press the button next to the or symbols to move to the numeric character you wish to change.
  3. Press the button next to the + symbol to increase the value; press the button next to the − symbol to decrease the value.
  4. After adjusting, press the symbol to save; make sure the cursor is on the last numeric character before pressing.
Adjusting Values/Parameters (PowerCommand 2100 Control) adjustment
  1. Press the button next to the down arrow symbol until the + and - symbols are displayed.
  2. Press the button next to the arrow symbols to move to the numeric character to be changed.
  3. Press the button next to + to increase the value or select a parameter; press - to decrease.
  4. Press the save symbol to save the changes (make sure the cursor is on the last numeric character).
  5. If the Home button or Previous Main Menu button is pressed before the save symbol, the changes are not saved.
Controller Configuration (PowerCommand 2100 Control) adjustment
  1. Make sure Main Menu 1 is displayed.
  2. Simultaneously press the Home Menu and Previous Main Menu buttons to view the first Controller Configuration menu.
  3. Press the buttons next to the up and down symbols to navigate between menus.
  4. Press the button next to the + or - symbol to select the desired option.
  5. Press the save symbol to save changes; pressing Home or Previous Main Menu before the save symbol leaves changes unsaved.
Convert Day Tank Controller 240 VAC to 120 VAC adjustment
  1. Remove the two jumpers between terminals TB1-6 and TB1-7.
  2. Connect one jumper between TB1-5 and TB1-6 and the other between TB1-7 and TB1-8.
  3. Move selector switch S103 on the control PCB to the up position for 120V.
  4. If equipped with a transformer, remove jumpers between H2 and H3 and connect one between H1 and H3 and the other between H2 and H4.
Day Tank Controller Conversion 240 VAC to 120 VAC adjustment
  1. Remove the two jumpers between terminals TB1-6 and TB1-7 and connect one between TB1-5 and TB1-6 and the other between TB1-7 and TB1-8.
  2. Move selector switch S103 on the control PCB to the up position for 120V.
  3. On the control transformer, remove the two jumpers between terminals H2 and H3 and connect one between H1 and H3 and the other between H2 and H4.
Dip Adjustment adjustment
  1. Turn the DIP pot clockwise to increase the voltage vs frequency slope for frequencies below the UFRO threshold.
  2. Greater slope gives greater voltage roll off as frequency drops, easing large load pickup but increasing voltage dip.
  3. Turn the pot fully counterclockwise to make the slope the same above and below the threshold frequency.
Dwell Adjustment adjustment
  1. Turn the DWELL pot clockwise to increase dwell time (voltage recovery time when frequency dips below threshold).
  2. Turn the DWELL pot fully counterclockwise to eliminate dwell.
  3. With no dwell, voltage recovery follows engine speed recovery.
Electric Governor Controller Adjustments adjustment

⚠ If adjustment must be made while the unit is running, use extreme caution around hot manifolds and moving parts

Tools: Frequency meter

  1. Move RUN/STOP/REMOTE switch to RUN and operate set at no load.
  2. Confirm DROOP potentiometer adjust is set at zero position.
  3. Set speed by adjusting the SPEED potentiometer to 50 or 60 Hz.
  4. Adjust GAIN potentiometer clockwise until engine starts to hunt, then counterclockwise until speed is stable.
  5. Adjust the 'B' potentiometer the same as GAIN.
  6. Adjust the 'I' potentiometer to decrease overshoot above rated speed.
  7. Apply 1/4 load and adjust the GAIN potentiometer again.
  8. Apply full load to be certain the set will carry it; lengthen actuator linkage if it will not.
Fuel Pump Control: Convert 120 VAC to 240 VAC adjustment
  1. Remove jumpers between TB1-5/TB1-6 and TB1-7/TB1-8; connect two jumpers between TB1-6 and TB1-7.
  2. Move selector switch S103 on control PCB to down position for 240 VAC.
  3. If equipped with a transformer, remove jumpers between H1/H3 and H2/H4 and connect two jumpers between H2 and H3.
  4. Attach a tag to the control box indicating the supply voltage.
Fuel Pump Control: Convert 240 VAC to 120 VAC adjustment
  1. Remove jumpers between TB1-6/TB1-7; connect one jumper TB1-5 to TB1-6 and one TB1-7 to TB1-8.
  2. Move selector switch S103 on control PCB to up position for 120V.
  3. If equipped with a transformer, remove jumpers between H2/H3 and connect one between H1-H3 and one between H2-H4.

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

VoltagePhaseConnectionLeadsNotes
AVR response jumperA to CFor generator output 90 kW or less (SX440 and MX321)
Auxiliary terminal board TB21K1, K2, P2, P3, P4, S2, S1, A2, A1A1 and A2 connect a VAR/power factor controller when paralleling with a utility; S1 and S2 connect a droop compensating CT when paralleling with a generator set or utility
CT1 - U load leads (A phase); CT2 - V load leads (B phase); CT3 - W load leads (C phase)6 lead gensets: generator output leads routed through CTs; 12 lead gensets: load wires routed through CTs12-lead sets have dual secondary CTs (3 pins); 6-lead sets have single secondary CTs (2 pins)
Day tank LO SHUTDOWN engine shutdown connectionTB1-14 to engine block ground; TB1-15 to TB2-16 on the ECM
Fault relay K8/K9 (Dry Contact Module)K8=Over Crank, Low Oil Pressure, High Engine Temperature, Low Coolant Level, Low Fuel Level; K9=Low Fuel Level, Rupture BasinContact ratings: 40A max carry/break N.O. 12V coil, 30A N.C. 12V coil, 20A N.O./10A N.C. 24V coil
MX321 PMG-excited jumper positions2-3, 4-5 and 6-7These jumpers must be in these positions
MX321 voltage regulator frequency jumper3-2 for 50 Hz; 3-1 for 60 Hz
SX440 voltage regulator frequency jumperC-50 for 50 Hz; C-60 for 60 Hz
TB3 (ECM alternative RUN/STOP/REMOTE connection)TB3-1=REMOTE, TB3-2=RUN, TB3-3=STOPProvides alternative direct connection to ECM for troubleshooting or customer connection
Voltage trimmer R21voltage regulator terminals 1 and 2There must be a jumper between terminals 1 and 2 when voltage trimmer R21 is not used
single phaseQSG-Series power distribution panel voltage selector switch S1 positionmain output terminalsRotary switch under lockable cover selects 120/240 VAC single phase
single phaseVoltage regulator terminal 6jumpered to terminal 8When the generator is connected for single-phase output, terminal 6 is not connected to the isolation transformer
three phaseQSG-Series power distribution panel voltage selector switch S1 positionmain output terminalsRotary switch selects 120/208 VAC three phase
110V - 120V L-NSingle phase, 2-wireJumper locations for single phase, 2-wirePTC Module AC wiring (0300-5382-01, -02)
120single phaseDay tank fuel pump control power reconnectionmove jumpers from TB1-6/TB1-7 to TB1-5/TB1-6 and TB1-7/TB1-8Move selector switch S103 on the control PCB to the up position for 120 V (factory set for 240 V, S103 down)
190, 200, 208, 220, 230, 240, 380, 416, 440, 460, 600 (L-L)3 (three phase)3 or 4 wiresVoltage Configuration submenu; default = 3Ph 208V 4W
190V - 240V L-LThree phaseJumper locations for three phase, 190V-240V L-LUse 0300-5382-01 for 190V-240V L-L, 50/60 Hz
200, 220, 230, 240 (L-L)1 (single phase)3 wiresVoltage Configuration submenu (Governor/Regulator Setup)
200V - 240V L-LSingle phase, 3-wireJumper locations for single phase, 3-wirePTC Module AC wiring
24Day tank fuel pump control logic power (two lead harness, no transformer)TB1-19 to positive (+) 24 V starter motor solenoid; TB-20 to negative (-)Provides 24 VDC for the control circuit
240single phaseDay tank fuel pump control default factory connectionjumpers between terminals TB1-6 and TB1-7Selector switch S103 on the control PCB in the down position for 240 V
380V - 600V L-LThree phaseJumper locations for three phase, 380V-600V L-LUse 0300-5382-02 for 380V-600V L-L, 50/60 Hz

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

Which generators use the 4B/6B/6C engine?

The 4B/6B/6C powers 9 generator set(s), including Cummins/Onan DGBB, Cummins/Onan DGBC, Cummins/Onan DGCA, Cummins/Onan DGCC, Cummins/Onan DGDA.

How often should you change the oil in the 4B/6B/6C?

The 4B/6B/6C oil change interval is every 250 hours.

What is a common problem with the 4B/6B/6C engine?

A commonly reported issue on generators using the 4B/6B/6C is: Over Current.