Specifications
| Fuel | Natural Gas, Propane |
|---|---|
| Frequency | 60.0 Hz |
| Standby power | 10 kW |
| Oil capacity | 4.0 L |
| Voltage options | 12 V |
| Phase | Single Phase |
| Rated current | 65 A |
| Battery voltage | 12 V |
| Coolant capacity | 11 L |
Maintenance & consumables
for the Cummins/Onan 4-cyl.| Item | Spec | Capacity | Part # | Interval | |
|---|---|---|---|---|---|
| Air filter | To Service the Air Cleaner:1. Loosen clamps and remove air cleaner housing end cap.2. Remove the air filter element from the filter housing.3. To clean, blow low pressure compressed air (30 psi/207 kPa) through the element from the clean side. Hold the nozzle at least 1 inch (25 mm) away to avoid damaging the element.4. Soak the filter for at least 15 minutes in water and Donaldsons D1400 solvent to remove soot, carbon and dirt.5. Rinse with clean water (low pressure) and allow to air dry. Do not blow dry with compressed air. Reinstall when the filter element is dry. Replace the filter after two cleanings to avoid restricting the airflow. | — | 200 hr | ||
| Fuel filter | Spin off oil filter and discard it. Thoroughly clean filter mounting surface. Apply a thin film of oil to filter gasket and install new element. Spin element on by hand until gasket just touches mounting pad and then turn an additional 1/2 to 3/4 turn. Do not over-tighten (Figure 5-2). | — | |||
| Oil filter | Run engine until thoroughly warm before draining oil. Stop the set, place a pan under the drain outlet and remove the oil drain plug or open the drain valve. After the oil is completely drained, replace the drain plug or close the drain valve. Refill with oil of the correct API viscosity grade for the temperature conditions. | — | 200 hr | ||
| Battery | Check the battery connections to make sure they are clean and tight. A light coating of non-conductive grease will retard terminal corrosion. | — | 90 hr | ||
| Belt | An improperly adjusted fan belt can cause engine overheating and insufficient battery charging. Push on the fan belt in the middle and check that it deflects no more than 0.5 in. (13 mm) under a load of 15 lbs. (67 N). If belt is loose, loosen the two bolts on the battery charging alternator and adjust until proper tension is obtained. Retighten alternator bolts after adjustment. | — | 90 hr | ||
| Coolant | Check the coolant level during shutdown periods at the interval specified in Table 5-1. Use a 50/50 coolant solution (50% pure water and 50% antifreeze). Always keep level in the coolant recovery tank between low and full. | 11.0 L | — | 90 hr | |
| Oil | Check the engine oil level during engine shutdown periods at the intervals specified in the Maintenance Table. | — | 200 hr | ||
| Spark plug | Check and replace annually. | — | 365 hr |
Service specifications
52| Type | Item | Value | Unit | Condition |
|---|---|---|---|---|
| Gap | Speed sensor air gap | 0.020 | in. (0.508 mm) | |
| Gap | Speed sensor air gap | 0.36- 0.71 | mm | |
| Other | Exciter current delivery time (Fast-Response II) | 0.05 | seconds | change in load demand |
| Other | Overvoltage shutdown threshold | 15% or more over nominal | shutdown after approximately one second | |
| Pressure | Battery equalizer input voltage (24 volts nominal) | 20- 35 | volts | |
| Pressure | Battery equalizer output voltage | (input voltage/2) ±2% | volts | |
| Pressure | Low oil pressure shutdown (diesel models) | 5.5 to 10.5 | psi (38 to 72 kPa) | |
| Pressure | Low oil pressure shutdown (gasoline models) | 11.5 to 18.5 | psi (79 to 126 kPa) | |
| Pressure | Pressure switch 364345 | 483 ±14 | kPa | |
| Resistance | CR relay coil resistance | approximately 125 | Ohms | 12-Volt coil; measure between terminals A and B |
| Resistance | CR relay normally closed contacts (continuity) | 1-7, 2-8, 3-9 | ||
| Resistance | Exciter armature low resistance reading (faulty if below) | under 0.1-0.2 | ohms | |
| Resistance | Generator field F3-F4 continuity | 2-3.75 | ohms, +5% | |
| Resistance | Photo transistor board reading (covered) | 300K | ohms or higher | covered |
| Resistance | Photo transistor board reading (lit) | 5K | ohms or lower | bright flashlight on board |
| Resistance | Pressure sender 264390 value A | 240 +17/- 15 | ohms at 0 psi | |
| Resistance | Pressure sender 264390 value B | 153 +12/- 15 | ohms at 25 psi | |
| Resistance | Pressure sender 264390 value C | 33.5 | ohms at 100 psi | |
| Resistance | Pressure sender 365624 value A | 241 ±16 | ohms at 0 psi | |
| Resistance | Pressure sender 365624 value B | 152 ±13 | ohms at 50 psi | |
| Resistance | Pressure sender 365624 value C | 33.5 | ohms at 200 psi | |
| Resistance | Temperature sender 226717 value A | 123.8 +7.2/- 7.8 | ohms at 90.6 C (195 F) | |
| Resistance | Temperature sender 226717 value B | 35.6 +3.4/- 3.6 | ohms at 137.8 C (280 F) | |
| Resistance | Temperature sender 226919 value A | 942 ±22 | ohms at 37.7 C (100 F) | |
| Resistance | Temperature sender 226919 value B | 35 | ohms at 115.6 C (240 F) | |
| Speed | Governed speed (50 Hz models) | 1500 | rpm | |
| Speed | Governed speed (60 Hz models) | 1800 | rpm | |
| Speed | Governor speed droop | 3 Hz or 90 rpm | between no load and full load | |
| Speed | No-load frequency (50 Hz operation) | 53 | Hz | no load |
| Speed | No-load frequency (60 Hz operation) | 63 | Hz | no load |
| Speed | Overspeed shutdown | 70 | Hz | 60 Hz models |
| Speed | Overspeed shutdown (50 Hz sets) | 60 | Hz | |
| Speed | Overspeed shutdown (60 Hz sets) | 70 | Hz | |
| Temperature | Battery equalizer operating temperature | - 40 to 71 | C (- 40 F to 160 F) | |
| Temperature | Low water temperature start-up threshold | below 70 | °F (21°C) | 10-second start-up |
| Temperature | Temperature switch 241308 | 107 ±4 | C (225 F ±7 F) | normally open to close on temp. rise |
| Temperature | Temperature switch 290090/GM51705 | 16 ±3 | C (60 F ±5 F) | normally open to close on temp. fall |
| Torque | Drive disc mounting bolts | 50 | ft. lbs. (108.48 Nm) | |
| Torque | FR Activator mounting screws | 20-26 | in. lbs. (2.8-2.8 Nm) | |
| Torque | FR Activator terminal screws A and F | 20-25 | in. lbs. (2.3-2.8 Nm) | |
| Torque | Fan bolts | 260 | in. lbs. (29.4 Nm) | |
| Voltage | 1CR relay test voltage at P5 pin 10 to ground | 0.5 to 1.0 | volts | on-crank cycle |
| Voltage | Battery high volts lamp setpoint (12-volt systems) | 15 | volts | |
| Voltage | Battery high volts lamp setpoint (24-volt systems) | 30 | volts | |
| Voltage | Battery low volts lamp setpoint (12-volt systems) | 10 | volts | |
| Voltage | Battery low volts lamp setpoint (24-volt systems) | 20 | volts | |
| Voltage | CR relay test voltage at P5 pin 9 to ground | 0.5 to 1.0 | volts | Generator Master Switch in TEST position |
| Voltage | High voltage test (exciter armature A1 or A2 to rotor shaft) | 4,100 | volts AC | not more than one second |
| Voltage | High voltage test (generator field F3 or F4 to shaft) | 1,100 | volts AC | not more than one second; do not repeat test |
| Voltage | LED board output at 3B(+) and 5B(-) | 1-2 | Volts DC | generator set running |
| Voltage | Speed sensor voltage, wire 2 (black) & 16 (white) | 3- 6 | volts DC | |
| Voltage | Speed sensor voltage, wire 2 (black) & 24 (red) | 8- 10 | volts DC |
Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.
Procedures
12Bosch Electronic Governor Stability and Gain Adjustment adjustment
- Check that the stability control is in its extreme counterclockwise position.
- Start engine. Allow the governor to control the engine. If engine is unstable, turn the gain control counterclockwise until stability is obtained. Adjust speed screw to proper engine speed.
- Turn the gain control clockwise until the engine becomes just unstable. Back the gain control slightly counterclockwise until the engine is again stable.
- Turn the stability control clockwise until the engine becomes just unstable. Back the stability control slightly counterclockwise until the engine is again stable.
Diesel Mechanical Governor Frequency Adjustment adjustment
Tools: Frequency meter
- Start the generator set, observe the frequency meter.
- Loosen the fuel pump high speed screw locknut to make the adjustments.
- To increase or decrease the frequency (at no load), rotate the screw clockwise or counterclockwise respectively.
- Tighten the locknut.
- Loaded droop frequency may alternately be adjusted to the operating frequency at full load.
Gas/Gasoline Mechanical Governor Speed and Sensitivity Adjustment adjustment
Tools: Hand tachometer, Frequency meter
- With the set running at full or rated load, check speed with hand tachometer or frequency meter.
- Loosen locking nut on speed adjusting screw; turn clockwise to increase speed (and frequency) or counterclockwise to decrease; lock nut at new setting.
- For sensitivity, loosen the nut at bottom of adjusting eyebolt and tighten the top nut to draw the head of the eyebolt closer to the governor arm pivot point (more sensitive).
- To make governor control less sensitive, loosen the top nut and tighten the bottom nut to move the head away from the pivot point.
- Recheck speed after sensitivity adjustment since changing this will also affect speed.
Generator Frequency Change (60 Hz to 50 Hz) adjustment
Tools: Frequency meter
- On Microcomputer equipped generators, snip the jumper indicated in Figure A1 to convert from 60 Hz to 50 Hz.
- Check frequency meter for a no load reading of 63 Hz for 60 Hz operation and 53 Hz for 50 Hz operation.
- If equipped with isochronous governor, check for 60 and 50 Hz operation at no load.
- If no frequency meter, connect meter across VO and V7 on control board terminal strip (set must not be running while making connection).
High and Low Battery Voltage Indicator Adjustment adjustment
Tools: DC power supply
- Move Generator Master Switch to AUTO position. SYSTEM READY lamp should go on.
- Rotate potentiometers R42 (High Batt. Volts) and R25 (Low Batt. Volts) fully counterclockwise.
- Set DC power supply at 10 volts (20 volts for 24-volt units). Slowly rotate pot R25 clockwise until BAT. LOW VOLTS lamp lights.
- Set DC power supply at 15 volts (30 volts for 24-volt units). Slowly rotate pot R42 clockwise until BAT. HIGH VOLTS lamp lights.
- Set DC power supply between 10 to 15 volts (20 to 30 volts for 24-volt units). SYSTEM READY lamp should be on.
- Seal pots after settings have been established.
Overfrequency Adjustment (Over/Underfrequency Relay, Decision-Maker 3+) adjustment
- Turn the overfrequency adjustment potentiometer fully clockwise (CW).
- Place master switch in RUN to start the generator set.
- Adjust governor per engine operation manual, engine service manual, or governor section of this manual.
- Slowly turn overfrequency potentiometer counterclockwise (CCW) until the LED starts flashing; after about 10 seconds the set shuts down on auxiliary fault.
- Place master switch to OFF/RESET to reset the controller.
- Place master switch to RUN to start the generator set.
- Readjust the governor to the desired frequency as required.
- Place master switch to OFF/RESET to stop the generator set.
Overvoltage Feature Testing and Adjustment (Decision-Maker 3+) adjustment
⚠ Hazardous voltage. Moving parts. Will cause severe injury or death. Operate the generator set only when all guards and electrical enclosures are in place.
⚠ Disconnecting the electrical load. Hazardous voltage will cause severe injury or death.
- Disconnect generator set from load by opening line circuit breaker or disconnecting and taping output leads.
- Determine overvoltage shutdown value based on user requirement; factory setting is 15% above nominal line-to-neutral voltage.
- Remove the controller cover.
- Place master switch in RUN to start the generator set.
- Observe AC voltmeter; turn voltage adjustment potentiometer CW until generator set shuts down.
- If the shutdown point is correct, go to step 12; otherwise continue.
- Turn controller circuit board R42 adjustment potentiometer fully CW.
- Place master switch to OFF/RESET to reset; then to RUN to start.
- Observe AC voltmeter while turning voltage adjustment potentiometer to desired overvoltage shutdown point.
- Turn R42 adjustment potentiometer slowly CCW until the generator set shuts down.
- Turn controller voltage adjustment potentiometer slightly CCW.
- Place master switch OFF/RESET then RUN to start; adjust for correct voltage and phase.
- Place master switch OFF/RESET to stop.
- Disconnect battery negative lead first; reconnect generator set to load; reconnect battery negative lead last.
Reactive Droop Compensator Adjustment Procedure adjustment
Tools: Voltmeter, Wattmeter
- Remove any load; start each generator set with master switch in RUN.
- Set reactive droop compensator rheostat on generator set no. 1 to minimum CCW; record rpm/frequency and voltage at 1/4 load steps to full load.
- Repeat for generator set no. 2.
- Compare readings; adjust voltage within 1 volt and speed within 3 rpm (or 0.1 Hz) at each load step.
- Check droop compensation on each unit with an inductive load 1/2 to full load.
- Adjust rheostat to approximately 4% below rated voltage at full load.
- Repeat for unit no. 2.
Reactive Droop Compensator Alternate Adjustment Procedure adjustment
Tools: Voltmeter
- Turn reactive droop compensator rheostat on generator set no. 1 to minimum setting.
- Remove controller cover; move voltage sensing lead from V7 to V9 at the AC fuse terminal block.
- Remove any load connected to the generator set.
- Start the generator set with master switch in RUN.
- Use controller or remote voltage adjusting potentiometer to fine adjust voltage.
- Apply resistive load (1.0 power factor) until reaching rated current.
- Adjust reactive droop compensator rheostat to achieve a 4% droop in voltage.
- Remove the resistive load and stop the generator set.
- Return voltage sensing lead from V9 to V7 at the AC fuse terminal block.
- Replace the controller cover and repeat for generator set no. 2.
Underfrequency Adjustment (Over/Underfrequency Relay, Decision-Maker 3+) adjustment
- Turn underfrequency adjustment potentiometer fully clockwise (CW).
- Place master switch in RUN to start the generator set.
- Adjust governor per engine operation manual, engine service manual, or governor section of this manual.
- Slowly turn underfrequency potentiometer counterclockwise (CCW) until LED starts flashing; after about 10 seconds the set shuts down on auxiliary fault.
- Place master switch to OFF/RESET to reset the controller.
- Place master switch to RUN to start the generator set.
- Readjust the governor to the desired frequency as required.
- Place master switch to OFF/RESET to stop the generator set.
2-Wire Low Water Level Sender Test diagnostic
⚠ Hot engine and exhaust system can cause severe injury or death. Do not work on the generator set until it cools.
⚠ Hazardous voltage. Moving parts. Will cause severe injury or death. Operate the generator set only when all guards and electrical enclosures are in place.
Tools: DC voltmeter
- Measure DC voltage between lead 31A (+) and ground (- ) with sender submerged in coolant; voltmeter indicates approximately 12.5 VDC.
- Measure DC voltage between lead 31A (+) and ground (- ) with sender removed from coolant for at least 5-15 seconds; voltmeter indicates a drop to approximately 7 VDC.
3-Wire Low Water Level Sender Test diagnostic
⚠ Hot engine and exhaust system can cause severe injury or death. Do not work on the generator set until it cools.
⚠ Hazardous voltage. Moving parts. Will cause severe injury or death.
Tools: Ohmmeter
- Measure resistance between lead 31 and ground with sender submerged in coolant; ohmmeter indicates a high resistance reading.
- Measure resistance between lead 31 and ground with sender removed from coolant for at least 5-15 seconds; ohmmeter indicates a low resistance reading.
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 |
|---|---|---|---|---|
| 120/208 or 139/240 | 3-Phase | 4-Wire Low Wye | 60Hz, 120/208-Volt or 139/240-Volt 3-Phase, 4-Wire Low Wye; 50Hz, 120/208-Volt or 110/190-Volt 3-Phase, 4-Wire Low Wye | |
| 120/240 | 1-Phase | 3-Wire | 60Hz, 120/240-Volt, 1-Phase, 3-Wire; 50Hz, 110/220-Volt, 1-Phase, 3-Wire | |
| 120/240 | 3-Phase | 4-Wire Delta | 60Hz, 120/240-Volt, 3-Phase, 4-Wire, Delta; 50Hz, 110/220-Volt, 3-Phase, 4-Wire, Delta. CT3 - Not Used | |
| 277/480 | 3-Phase | 4-Wire High Wye | 60Hz, 277/480-Volt, 3-Phase, 4-Wire High Wye; 50Hz, 220/380-Volt, 3-Phase, 4-Wire High Wye |
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
How many kW is the Cummins/Onan LSG-423?
The Cummins/Onan LSG-423 is rated 10 kW standby.
What engine does the Cummins/Onan LSG-423 use?
The Cummins/Onan LSG-423 is powered by the Cummins/Onan 4-cyl. engine.
What fuel type does the Cummins/Onan LSG-423 take?
The Cummins/Onan LSG-423 runs on Natural Gas, Propane.
What's the oil capacity on a Cummins/Onan LSG-423?
The Cummins/Onan 4-cyl. engine in the Cummins/Onan LSG-423 has an oil capacity of 4.5 liters.
How much coolant does the Cummins/Onan LSG-423 hold?
The Cummins/Onan LSG-423 cooling system holds 11 liters (2.9 US gallons) for the radiator system including the engine, per the manufacturer specification sheet.
What voltage does the Cummins/Onan LSG-423 produce?
The Cummins/Onan LSG-423 is offered in 12 V, Single Phase-phase.
Troubleshooting
6Symptoms & remedies
| Symptom | Cause | Remedy |
|---|---|---|
| Green RUN lamp lights following engine startup | Indicates all engine systems are normal. No corrective action required. | |
| PRE HET/LOP lamp lights. Engine continues to operate | Engine has begun to overheat and engine temperature has risen to approximately 205°F (97° C) or coolant level is low | If generator is powering non-critical and critical loads and cannot be shut down, use the following: Reduce load if possible by turning off non-critical loads; Check air inlets and outlets and remove any obstructions to airflow |
| HI ENG TEMP lamp lights. Engine shuts down | Engine has overheated (engine temperature has risen above 215°F/102°C) or coolant level is low | Allow engine to cool down completely before proceeding with the following checks: Check coolant level and replenish if low. Look for possible coolant leakage points and repair if necessary; Check for obstructions to cooling airflow and correct as necessary; Check for a slipping fan belt and tighten if loose; Reset control and restart after locating and correcting problem. Contact an authorized service center if none of the above |
| LO OIL PRES lamp lights. Engine shuts down | Engine oil pressure has dropped to 25 psi (172 kPa) | Check oil level, lines and filters. If oil system is OK but oil level is low, replenish. Reset control and restart. Contact an authorized service center if oil pressure is not in the range of 40 to 65 psi (275 to 448 kPa) |
| OVERCRANK lamp lights and engine stops cranking. or Engine runs, shuts down, and LO OIL PRES lamp lights | Possible fuel system problem | Check for empty fuel tank (LPG Vapor), fuel leaks, or plugged fuel lines and correct as required; Check for dirty fuel filter and replace if necessary (see Maintenance section); Check for dirty or plugged air filter and replace if necessary (see Maintenance section); Reset the control and restart after correcting the problem. Contact an authorized service center for service if none of the above |
| Engine runs and then shuts down, OVERSPEED lamp lights | Engine has exceeded normal operating speed | Contact an authorized service center for service |
Fault codes and symptom→remedy steps extracted from this model’s service/owner documentation; verify against the official manual before servicing. Full Cummins/Onan LSG-423 troubleshooting guide (23 entries) →
Repair guides
14- Bosch Electronic Governor Stability and Gain Adjustment
- Diesel Mechanical Governor Frequency Adjustment
- End Bracket Removal
- Exciter Armature Test
- FR Activator Replacement
- Gas/Gasoline Mechanical Governor Speed and Sensitivity Adjustment
- Generator Field Continuity and High Voltage Test
- Generator Frequency Change (60 Hz to 50 Hz)
- Generator Reconnection (Voltage Change)
- High and Low Battery Voltage Indicator Adjustment
- LED Circuit Board (Flashlight) Test
- Photo Transistor Board Test
- Resetting After Fault Shutdown (Microcomputer Controller)
- Stopping the Generator Set (Microcomputer Controller)
Step-by-step procedures compiled from the Cummins/Onan service manual for this model.
Parts
3| Part # | Description | Qty | System | |
|---|---|---|---|---|
| 928-0129 | Oil Filter | 2 | Oil filter | Amazon eBay |
| LS1169s | FILTER | 1 | Oil filter | Amazon eBay |
| 928-0608 | Manual, Onan Installation | 1 | 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.
Available documents
Spec sheet — tp5750fSpec sheet — tp6356es (Unknown (TP-6356-ES))Reference — tp5750s (Kohler)Parts manual — pb31 (Various (Cummins, Ford, John Deere, DDC))Parts manual — tp5543 (Kohler)Parts manual — tp5704 (Kohler)Service manual — 928-0127 Onan 10 GEAA 20 GEAB Operator's Manual (4-1994) (Cummins/Onan)Service manual — TP-6356 (Kohler)Service manual — sb575Service manual — tp5149 (Kohler)Service manual — tp5719 (Kohler)Service manual — tp6356 (Kohler)
This page was generated from the 12 manufacturer documents above by automated extraction; every figure shown is copied from one of them. How the data is compiled.