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Kohler 30REZG Generator Set

The Kohler 30REZG is a 30 kW (38 kVA) LP Gas standby generator set powered by a General Motors 3.0L engine. It is available at 480 V, 60 Hz. It holds about 4.7 L (1.2 gal) of oil and 14.9 L (3.9 gal) of coolant, with a maximum ambient rating of 50 °C. The set produces 74 dBA at 23 m. The same 3.0L engine also powers generator sets from Genie.

30 kW
Standby
3.0 L
Displacement
4.7 L
Oil capacity
5
Document types

How to read your Kohler serial & model number →

Compare with other 30–35 kW Propane/LPG generators →

Service parts for the 30REZG

Grouped by system, with how many of each the parts manual calls for.

Air intake

1 required

Oil system

1 required

Belts

1 required

Ignition

1 required
GM38998Spark plugsee priceAmazon

Prices captured from merchant listings; some links are affiliate links. Confirm against your serial number before ordering.

Specifications

FuelLP Gas
Frequency60.0 Hz
Standby power30 kW
Standby kVA38
Prime power27 kW
ControllerDecision-Maker 3000, Decision-Maker 3500
Oil capacity4.7 L
AlternatorFast-Response II (FRII)
Voltage options480 V
Coolant capacity14.9 L
Engine jacket water6.8 L
Max ambient50 °C
Sound level74.0 dBA @ 23 m

Engine

General Motors 3.0L
Oil capacity4.7 L
Coolant capacity14.9 L
Displacement3.0 L
AspirationNatural Aspiration
Rated speed1 rpm

Same engine, other brands

1 brand

The General Motors 3.0L in this set also powers 1 generator set sold under 1 other brand. Service parts and maintenance intervals for the engine are shared; enclosure, alternator, controller and ratings are not.

BrandModels
GenieS-80X

Maintenance & consumables

for the General Motors 3.0L
ItemSpecCapacityPart #Interval
Air filterElement, air cleaner253107 Amazon eBay $69.00 NAPA $55.23
Fuel filter—
Oil filterGM16703 Amazon eBay $58.00 NAPA $3.59
Battery—
BeltBelt, alternatorGM39428 Amazon eBay $15.00
Coolant—
Oil—
Spark plugSpark plugGM38998 Amazon eBay

Service intervals

14
ItemActionHoursMonthsNotes
Filter(s)Replace150 hr3 moService more frequently if operated in dusty areas
OilChange150 hr3 moEvery 150 Hours or 3 Months
Blow dust out of alternatorClean300 hr2 Yrs or 300 Hrs; service more frequently in dusty areas
Valve clearanceAdjust500 hr3 Yrs or 500 Hrs
Wire-cable insulation breakdownTest500 hr3 Yrs or 500 Hrs
CoolantChange1500 hr1500 Hours
Alternator end bracket bearingReplace10000 hr20--300 kW models; prime power applications
Coolant temperature protection levelCheck6 moSix Months
Paralleling boxInspect12 moAnnually by a Kohler authorized distributor/dealer, or when wear, damage, deterioration, or malfunction is evident or suspected.
Paralleling box internal componentsInspect1 moMonthly or when a condition noticed during external inspection may have affected internal components; enclosure cover must be removed by trained personnel.
Safety and alarm operationCheck6 moSix Months
Safety and alarm operationTest6 moSix Months
Tighten DC electrical connectionsCheck6 moSix Months
Wheel lug nut torqueCheckFirst service — First 80/160 km (50/100 miles); then Quarterly or 3000 Miles

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
Other10 in. weld flange bolt circle diameter B361.95mm (14.25 in.)
Other10 in. weld flange outside diameter C406.4mm (16.0 in.)
Other10 in. weld flange quantity of bolts / bolt hole diameter D12, 25.40mm (1.00 in.)
Other12 in. weld flange bolt circle diameter B431.80mm (17.00 in.)
Other12 in. weld flange outside diameter C482.6mm (19.0 in.)
Other12 in. weld flange quantity of bolts / bolt hole diameter D12, 25.40mm (1.00 in.)
Other14 in. weld flange bolt circle diameter B476.25mm (18.75 in.)
Other14 in. weld flange outside diameter C533.4mm (21.0 in.)
Other14 in. weld flange quantity of bolts / bolt hole diameter D12, 28.58mm (1.13 in.)
Other16 in. weld flange bolt circle diameter B539.75mm (21.25 in.)
Other16 in. weld flange outside diameter C596.9mm (23.5 in.)
Other16 in. weld flange quantity of bolts / bolt hole diameter D16, 28.58mm (1.13 in.)
Other18 in. weld flange bolt circle diameter B577.85mm (22.75 in.)
Other18 in. weld flange outside diameter C635.0mm (25.0 in.)
Other18 in. weld flange quantity of bolts / bolt hole diameter D16, 31.75mm (1.25 in.)
Other20 in. weld flange bolt circle diameter B635.00mm (25.00 in.)
Other20 in. weld flange outside diameter C698.5mm (27.5 in.)
Other20 in. weld flange quantity of bolts / bolt hole diameter D20, 31.75mm (1.25 in.)
Other5 in. weld flange bolt circle diameter B215.90mm (8.50 in.)
Other5 in. weld flange outside diameter C241.30mm (9.50 in.)
Other5 in. weld flange quantity of bolts / bolt hole diameter D8, 22.23mm (0.88 in.)
Other6 in. weld flange bolt circle diameter B254.0mm (10.0 in.)
Other6 in. weld flange outside diameter C279.4mm (11.0 in.)
Other6 in. weld flange quantity of bolts / bolt hole diameter D8, 22.23mm (0.88 in.)
Other8 in. weld flange bolt circle diameter B298.45mm (11.75 in.)
Other8 in. weld flange outside diameter C342.9mm (13.5 in.)
Other8 in. weld flange quantity of bolts / bolt hole diameter D8, 22.23mm (0.88 in.)
OtherAlternator protection current/time limits200%: 40 seconds; 300%: 10 seconds; 425%: 5 seconds; 950%: 1 secondrated current percentage
OtherBattery specific gravity (charge threshold)1.215specific gravityat 26.7 C (80 F); charge if below
OtherBattery specific gravity (fully charged)1.260specific gravityat 26.7 C (80 F) electrolyte temperature
OtherController operating temperature range--40 to 70 C (--40 to 158 F)
OtherController power drain400 milliamps at 12V; 200 milliamps at 24V
OtherEngine speed adjustment50default setting; settings between 40 and 60 acceptable; 52 increases speed by 2 RPM, 49 decreases by 1 RPM
OtherGaseous fuel tank maximum safe fill level80% of total fuel tank volume
OtherGenerator to bus phase angle-10 to 10degreesverify with contactor closed
OtherLP gas fuel system leak test pressure6--8 ounces per square inch (10--14 inches water column)oz/in2 (in. water column)test pressurized
OtherReactive droop1%default setting; range 0.5 - 2%
OtherWeld flange angle A (10, 12, 14 in. nominal pipe size)30deg.
OtherWeld flange angle A (16, 18, 20 in. nominal pipe size)22.5deg.
OtherWeld flange angle A (5, 6, 8 in. nominal pipe size)45deg.
OtherWheel stud size1/2-20
PressureFuel tank pressure relief valve (close)1937--2130kPa (281--309 psi)
PressureFuel tank pressure relief valve (open)2151kPa (312 psi) min
PressureTire inflation pressure @ rated load552 (80 psi)kPa (psi)
SpeedOverfrequency default setting110% of nominal%
SpeedOverfrequency setting range102%--140% of nominal%
SpeedOverfrequency time delay10sec
SpeedUnderfrequency default setting90% of nominal%
SpeedUnderfrequency setting range80%--95% of nominal%
SpeedUnderfrequency time delay10 (short term), 60 (long term)sec
Torque1-12 fastener283.0 (209)Nm (ft. lb.)Assembled into cast iron or steel, Grade 2 or 5
Torque1-8 fastener259.0 (191)Nm (ft. lb.)Assembled into cast iron or steel, Grade 2 or 5
Torque1/2-13 fastener60.0 (44)Nm (ft. lb.)Assembled into cast iron or steel, Grade 2 or 5
Torque1/2-20 fastener66.0 (49)Nm (ft. lb.)Assembled into cast iron or steel, Grade 2 or 5
Torque1/4-20 fastener6.8 (60)Nm (in. lb.)Assembled into cast iron or steel, Grade 2 or 5
Torque1/4-28 fastener8.1 (72)Nm (in. lb.)Assembled into cast iron or steel, Grade 2 or 5
Torque10-24 fastener2.9 (26)Nm (in. lb.)Assembled into cast iron or steel, Grade 2 or 5
Torque10-32 fastener2.9 (26)Nm (in. lb.)Assembled into cast iron or steel, Grade 2 or 5
Torque3/4-10 fastener199.0 (147)Nm (ft. lb.)Assembled into cast iron or steel, Grade 2 or 5
Torque3/4-16 fastener222.0 (164)Nm (ft. lb.)Assembled into cast iron or steel, Grade 2 or 5

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
GreaseLithium complexAxle bearing grease type
GreaseMultipurpose greaseLubricate trailer hitch/coupler contact points
GreasePetroleum jelly, silicon grease, or other nonconductive greaseCoat battery terminals after reconnecting
GreaseWhite lithium greaseApply a small amount behind the brake shoe where it rubs against the backing plate

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

42
CodeNameMeaningSeverityAction
AC Sensing LostWarning
Alternator ProtectionShutdown
Auxiliary InputWarning
Avg CurrentHighWarning
Avg Gen Voltage L-LLowWarning
Battery Charger FaultWarning
Cabinet Intrusion AlarmWarning
Coolant PressureLowWarning
Cranking VoltageLowWarning
ECM Communication LossShutdown
ECM Model MismatchShutdown
Electrical Metering Communication LossShutdown
Emergency StopShutdown
Engine Coolant LevelLowShutdown
Engine Coolant TemperatureLowWarning
Engine Derate ActiveWarning
Engine Fuel LevelLowWarning
Engine Oil LevelLowWarning
Engine Oil PressureShorted HighWarning
Failure To SynchronizeWarning
Fuel PressureLowWarning
Fuel Tank LeakWarning
Fuel TemperatureHighWarning
Gen Battery VoltageLowWarning
Generator FrequencyLowWarning
Generator Voltage L1-L2LowShutdown
Ground Fault InputWarning
Injector Wiring FaultWarning
Intake Air TemperatureHighWarning
Locked RotorShutdown
Maximum Alternator CurrentLowShutdown
Not In AutoWarning
Over CrankShutdown
Reserve Oil EmptyWarning
Run Relay Coil OverloadShutdown
Speed Sensor FaultWarning
Starter Relay Coil OverloadShutdown
System FrequencyHighWarning
System VoltageHighWarning
Total Power (Generator Total Real Power)LowWarning
Total Reactive PowerLowWarning
Water In FuelWarning

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
Calibration adjustment

⚠ Copying personality profiles from one controller to another can overwrite calibration coefficients and requires re-calibration.

Tools: Calibrated multimeter with recent calibration verification

  1. Use a calibrated multimeter to measure the generator voltage and enter the correct value in the CONTROLLER CONFIG -> CALIBRATION screen.
  2. Use a calibrated multimeter to measure the bus voltage and enter the correct value in the CONTROLLER CONFIG -> CALIBRATION screen.
Electric Brake Adjustment adjustment

⚠ Never use compressed air to clean brake components; some components may contain asbestos.

Tools: Adjustment tool or large slotted screwdriver, Jack stands

  1. Raise the trailer with wheels off the ground and block safely with jack stands; remove the wheel.
  2. Remove the rubber plug from the backing plate slot.
  3. Insert an adjustment tool or large slotted screwdriver in the slot and rotate the star wheel to expand the shoe against the drum.
  4. Expand the shoe until the drum can't be turned by hand to center each shoe.
  5. Back off the adjustment in the other direction until the drum turns freely with slight resistance.
  6. Replace the rubber plug in the backing plate slot.
  7. Repeat procedure for remaining wheels.
Verify Generator Operation diagnostic

⚠ Generators must all operate at the same frequency, voltage, and phase connection in order to parallel.

Tools: SiteTech software

  1. Ensure the load is not connected or is drawing less power than a single generator can provide.
  2. Navigate to CONTROLLER CONFIG -> COMMUNICATION SETUP and verify PGEN Nodes Online indicates the correct number of nodes.
  3. Verify alternator connection (voltage selector switch position), system voltage, and voltage regulator target on each generator.
  4. Start a single generator by pressing the Run button; the paralleling box contactor should close and the Generator Connected to Bus indicator should light.
  5. Verify bus and generator voltages match and generator to bus phase angle is between -10 and 10 degrees.
  6. Verify the load bus is energized and available at the load.
  7. Stop the generator by pressing the OFF button; the contactor should open.
  8. Repeat for each generator in the paralleling system.
Verify Paralleling and Load Sharing diagnostic

Tools: Load bank (optional)

  1. Place all generators in automatic mode by pressing the Auto button; verify the red shutdown indicator is not illuminated.
  2. Provide a local start request by holding AUTO, pressing RUN, releasing RUN, then releasing AUTO.
  3. Verify all generators start, one generator closes its contactor, and the others synchronize and close their contactors.
  4. Verify that the % of rated power of the generators matches, showing the generators are sharing load equally.
  5. If a load bank is available, test the system under load.
Common Hardware Application installation
  1. Determine entry hole type: round or slotted.
  2. Determine exit hole type: fixed female thread (weld nut), round, or slotted.
  3. For round and slotted exit holes, determine if hardware is greater than 1/2 inch in diameter.
  4. Hardware greater than 1/2 inch in diameter uses a standard nut and SAE washer.
  5. Hardware 1/2 inch or less in diameter can use a properly torqued whiz nut or spiralock nut.
  6. Always use a washer between hardware and a slot.
  7. Always use a washer under a nut.
  8. Use a washer under a bolt when the female thread is fixed (weld nut).
Control Harness Connections installation

⚠ The control harness connections for GEN 1 and GEN 2 must correspond to the source camlock cable connections.

  1. Connect the control harness from the generator set connected to the GEN 1 camlock connectors to GEN 1 CONTROL.
  2. Connect the control harness from the generator set connected to the GEN 2 camlock connectors to GEN 2 CONTROL.
  3. When not used, store the control harnesses on the storage rack inside the enclosure.
Grounding installation

⚠ Grounding electrical equipment: hazardous voltage can cause severe injury or death. Turn off the main circuit breakers of all power sources before servicing.

  1. Connect the ground lug on the paralleling box to earth ground according to applicable state and local codes.
  2. Follow NEC guidelines for grounding electrical equipment.
  3. The neutral is bonded to ground inside the paralleling box; if required, remove the bonding bus to disconnect neutral from ground.
Load Connections installation

⚠ Multiple power sources can automatically energize the distribution bus. Disconnect all power sources before connecting to the distribution bus.

  1. Remove the camlock security guard from one row of connectors for each generator and store the guard.
  2. Connect the load side ground (green) camlock cables to the distribution bus and then to the paralleling box.
  3. Connect the load side neutral (white) camlock cables to the distribution bus and then to the paralleling box.
  4. Connect the load side L1 (black), L2 (red), and L3 (blue) camlock cables to the distribution bus and then to the paralleling box.
Multiple Paralleling Boxes (PGEN Connections) installation
  1. Connect one or two generators to each paralleling box.
  2. Use Belden cable #9841 (or equivalent) shielded twisted-pair communication cable to connect the PGEN terminal blocks on the paralleling boxes.
  3. Tighten the connections to 0.5 Nm (4.4 in. lbs.).
Paralleling System Setup installation

⚠ Generator management must be disabled manually at each generator set controller.

Tools: Personal computer with SiteTech software

  1. Check that the voltage selector switch and/or alternator wiring matches the building voltage configuration for all generator sets.
  2. Set the digital output to Contactor (SiteTech Programmable Digital Output 116).
  3. Set reactive droop to 0.5-2% (default 1%), using the same reactive droop setting on all generators.
  4. Set the target voltage on all paralleled generators to the same value.
  5. Set engine speed adjustment to 50 on all generators (default 50; range 40-60).
  6. Verify metering; if voltage is incorrect, use the calibration procedure.
  7. Set Sync Mode in AUTO to ACTIVE and Sync Mode in Run to CHECK on all generators.
  8. Set Generator Management Enabled to OFF at each generator unless generator management is requested.
  9. Set up load management (load shed priorities) for non-critical loads.
  10. Stop all generators by pressing the OFF button on each controller.
Source Connections installation

⚠ Hazardous voltage. This equipment must be installed and serviced by qualified electrical personnel. Do not connect or disconnect cables under load.

  1. Remove the camlock security guard from one row of connectors for each generator and store the guard.
  2. Generator 2 connects to the upper set of camlocks; generator 1 connects to the lower set.
  3. Connect the source side ground (green) camlock cables to the paralleling box first and then to each generator.
  4. Connect the source side neutral (white) camlock cables to the paralleling box first and then to each generator.
  5. Connect the source side L1 (black), L2 (red), and L3 (blue) camlock cables to the paralleling box first and then to each generator.
Voltage Reconnection Procedure (with Selector Switch) installation

⚠ Do not move the voltage selector switch while the generator set is running.

⚠ Affix voltage reconnection decal 246242 after reconnecting to a different voltage.

Tools: User-supplied load lug wrench

  1. Press the generator set master control OFF/RESET button.
  2. Open the main line circuit breaker.
  3. Navigate to Generator Info then Voltage Selector Switch menu; press the selector dial.
  4. Select Present Position and change to the desired selection (Three Phase Wye 480 V, Three Phase Wye 208 V, or Single Phase Dogleg).
  5. Rotate the voltage selector switch on the junction box to match the desired voltage shown on the controller.
  6. Disconnect the engine starting battery, negative lead first; disconnect battery charger power.
  7. Make lead connections between load devices and the load lugs or camlocks.
  8. Make a ground connection to earth ground per NEC guidelines.
  9. Replace all electrical guards, barriers, and covers.
  10. Reconnect the battery, negative lead last; reconnect battery charger power.
  11. Press RUN to start and check voltages on the display.
  12. Press OFF/RESET to stop.
  13. Close the main line circuit breaker and any downstream circuit breakers.

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
12-LeadAlternator Reconnections diagram ADV-5875B-M (page 16)
4-LeadAlternator Reconnections diagram ADV-5875A-M (page 15)
1Camlocks (left to right)Green=GND; White=L0; Black=L1; Red=L2Single-phase uses four camlocks
3Camlocks (left to right)Green=GND; White=L0; Black=L1; Red=L2; Blue=L3Three-phase uses all five camlocks
120/2083Low wyeL0-L1: 120; L1-L2: 208; L1-L3: 208; L2-L3: 208Voltage selector switch position Low wye; selector switch factory set Pos. 2 Volts 120/208, 60 Hz, Three Phase Wye
120/2401Single-phaseL0-L1: 120; L1-L2: 240Voltage selector switch position Single-phase; selector switch factory set Pos. 3 Volts 120/240, 60 Hz, Single Phase Dogleg (3-position switch only)
277/4803High wyeL0-L1: 277; L1-L2: 480; L1-L3: 480; L2-L3: 480Voltage selector switch position High wye; selector switch factory set Pos. 1 Volts 277/480, 60 Hz, Three Phase 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

What is the power rating of the Kohler 30REZG?

The Kohler 30REZG is rated 30 kW standby (38.0 kVA).

What engine is in the Kohler 30REZG?

The Kohler 30REZG is powered by the General Motors 3.0L engine.

What fuel does the Kohler 30REZG use?

The Kohler 30REZG runs on LP Gas.

How much oil does the Kohler 30REZG take?

The General Motors 3.0L engine in the Kohler 30REZG has an oil capacity of 4.7 liters.

How much coolant does the Kohler 30REZG hold?

The Kohler 30REZG cooling system holds 14.9 liters (3.9 US gallons) for the radiator system including the engine, per the manufacturer specification sheet.

What is the continuous rating of the Kohler 30REZG?

The Kohler 30REZG is rated 27 kW prime (27 kVA), against 30 kW standby.

How loud is the Kohler 30REZG?

The Kohler 30REZG is rated at 74.0 dBA at 23 m, per the manufacturer specification sheet.

What voltages is the Kohler 30REZG available in?

The Kohler 30REZG is offered in 480 V.

What alternator comes on the Kohler 30REZG?

The Kohler 30REZG uses a Fast-Response II (FRII) alternator.

Which oil filter part number does the Kohler 30REZG take?

The Kohler 30REZG uses oil filter part number GM16703.

Which air filter part number does the Kohler 30REZG take?

The Kohler 30REZG uses air filter part number 253107.

Troubleshooting

6

Symptoms & remedies

SymptomRemedy
Osed moving partsKeep hands, feet, hair, clothing, and test leads away from the belts and pulleys when the generator set is running. Replace guards, screens, and covers before operating the generator set.
Unbalanced weightDo not use lifting eyes. Lift the generator set using lifting bars inserted through the lifting holes on the skid.
Hot coolant and steamBefore removing the pressure cap, stop the generator set and allow it to cool. Then loosen the pressure cap to relieve pressure.
Hot engine and exhaust systemDo not work on the generator set until it cools.
Servicing the exhaust system. Hot partsDo not touch hot engine parts.
Voltage reconnectionAffix a notice to the generator set after reconnecting the set to a voltage different from the voltage on the nameplate. Order voltage reconnection decal 246242 from an authorized service distributor/dealer.

Fault codes and symptom→remedy steps extracted from this model’s service/owner documentation; verify against the official manual before servicing. Full Kohler 30REZG troubleshooting guide (10 entries) →

Parts

18
Part #DescriptionQtySystem
253107Element, Air Cleaner1Air filter Amazon eBay $69.00 NAPA $55.23
4024TF281Fan Belt1Belt Amazon eBay
GM16132Belt, fan standard1Belt Amazon eBay $86.00
GM16531Spark plug1Spark plug Amazon eBay $8.08 NAPA $5.38
GM16703Filter, oil1Oil filter Amazon eBay $58.00 NAPA $3.59
GM19726Thermostat1Thermostat Amazon eBay
GM22171Spark plug8Spark plug Amazon eBay
GM34935Fuel Filter1Fuel filter Amazon eBay $37.99 NAPA $15.28
GM38998Spark plug1Spark plug Amazon eBay
GM39428Belt, alternator1Belt Amazon eBay $15.00
GM39458Coolant Temperature Sender (Decision-Maker 3+)1Sensor Amazon eBay
GM62309Element, air cleaner1Air filter Amazon eBay $91.00
GM63750Oil Filter1Oil filter Amazon eBay
GM63809Fuel Filter (primary)1Fuel filter Amazon eBay
GM65427Belt, alternator1Belt Amazon eBay $79.00
GM74021-CPipe sealantFluid Amazon eBay
GM79585--SThermostat1Thermostat Amazon eBay eBay
1259369GTMaintenance Inspection ReportService 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

RatingLoadL/hgal/h
Prime25%138.036.46
Prime50%192.050.72
Prime75%251.066.31
Prime100%314.082.95
Prime110%345.091.14
Standby25%144.038.04
Standby50%204.053.89
Standby75%271.071.59
Standby100%345.091.14

Available documents

Spec sheet (Kohler)Spec sheet — Towable Mobile Generators Brochure (Kohler)Operator's manual — tp6935 (Kohler)Reference (Kohler)Reference — G6-39 0918AZ (Kohler)Reference — Reinstated Enclosures (Kohler)Parts manual — tp6667 (Kohler)Parts manual — tp6801 (Kohler)Parts manual — tp6937 (Kohler)Service manual — sb710 (Kohler)Service manual — tp6712 (Kohler)Service manual — tp6799 (Kohler)Service manual — tp6936 (Kohler)Service manual — tt1672 (Kohler)

This page was generated from the 14 manufacturer documents above by automated extraction; every figure shown is copied from one of them. How the data is compiled.

A real unit
Kohler 30REZG generator

Photo of a real Kohler 30REZG — from a surplusrecord.com listing, 2026.

Real-unit nameplate
Kohler 30REZG generator nameplate / data tag

Nameplate from a real Kohler 30REZG — from a surplusrecord.com listing, 2026. How to read one →

Full service, cheapest listings

Priced items from this model's own parts manual.

Air filter 253107$55.23
Oil filter GM16703$3.59
Belt GM39428$15.00
3 priced items$73.82