HomeKohlerKohler PRO 12.3 EFI

Kohler PRO 12.3 EFI Generator Set

The Kohler PRO 12.3 EFI is a 10.5 kW (10500 kVA) gasoline standby generator set. It is available at 120 V and 14 V. The set measures 894×568×769 mm (35.2×22.4×30.3 in) and weighs about 139 kg (306 lb). An integrated tank holds 32.9 L (8.7 gal).

10 kW
Standby
3
Document types

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Specifications

Fuelgasoline
Standby power10 kW
Standby kVA10500
Prime power10 kW
Voltage options120 V, 30 V, 14 V
Dimensions (L×W×H)894×568×769 mm
Dry weight139 kg
Fuel tank32.9 L

Maintenance & consumables

ItemSpecCapacityPart #Interval
Air filterprecleaner25 hr find
Fuel filterunique Electronic Fuel Injection (EFI) fuel filter200 hr find
Oil filter200 hr find
Oil100 hr

Common questions

What is the power rating of the Kohler PRO 12.3 EFI?

The Kohler PRO 12.3 EFI is rated 10 kW standby (10500.0 kVA).

What fuel does the Kohler PRO 12.3 EFI use?

The Kohler PRO 12.3 EFI runs on gasoline.

Troubleshooting

27

Symptoms & remedies

SymptomCauseRemedy
No AC outputCircuit breaker in OFF position.Switch circuit breaker to ON.
Engine not operating at rated RPMAdjust engine running at normal operating temperature to 3600 ± 100 RPM.
Circuit breaker or receptacles faultyTest for voltage at circuit breaker and receptacles.
Stator is faultyTest for voltage and resistance.
Alternator can't output rated powerEngine not operating at rated RPM.Adjust engine running at normal operating temperature to 3600 ± 100 RPM.
Overload conditionCalculate electrical power required by electric appliances (in watts). Reduce total wattage of connected electric devices within application range.
Appliance is faultyRepair faulty appliance.
Alternator excitation failureEngine not operating at rated RPM.Adjust engine running at normal operating temperature to 3600 ± 100 RPM.
Faulty capacitorCheck and replace.
Faulty windingsCheck windings resistance.
High no load voltageEngine not operating at rated RPM.Adjust engine running at normal operating temperature to 3600 ± 100 RPM.
High capacity of capacitorCheck and replace.
Low no load voltageEngine not operating at rated RPM.Adjust engine running at normal operating temperature to 3600 ± 100 RPM.
Faulty rotor diodesCheck and replace.
Worn windingsCheck windings resistance.
Low capacity of capacitorCheck and replace.
Proper voltage at no load but low voltage at loadEngine not operating at rated RPM.Adjust engine running at normal operating temperature to 3600 ± 100 RPM.
Short-circuited rotor diodesCheck and replace.
Proper voltage in no load conditions but high voltage at loadEngine not operating at rated RPM.Adjust engine running at normal operating temperature to 3600 ± 100 RPM.
Unstable voltageLoose contacts.Check connections.
Uneven rotationCheck for uniform rotation speed.
Noisy alternatorWorn bearings.Replace.
Resistance value of stator winding out of specification or resistance to ground measuredReplace stator
Meter will not measure μF value of capacitorUse an analog or digital ohmmeter to verify if capacitor will charge and discharge. If meter maintains reading indicating open circuit, replace capacitor. If meter goes to very low value and stays there, the capacitor is short circuited and should be replaced.
No output from unit after flashing exciter windingApply a small amount of load to unit. If output occurs, let unit run for a while. If no output, rotor may not hold residual magnetism and may need replacement.
Alternator can’t output rated powerVerify engine speed at full load is 3600 RPM. Take a current reading of all loads, reduce if exceeding generator rating. Use a load bank and apply load while monitoring output voltage.
Engine Not Starting/Running AbnormallyEngine Stopped, No Electric Current, Tripping of Circuit BreakerLoad connected to generating set during start-up Start and Stop control ON or OFF Fuel valve closed Fuel level too low Unsuitable fuel Oil level too low Clogged air cleaner Clogged fuel filter Faulty starter battery. Fuel supply blocked or leaking Blocked ventilation inlets Circuit protectors not actuated Faulty appliance supply cord Faulty electrical sockets Faulty alternator Device connected or faulty cord Overload Battery incorrectly connected Faulty MODYS Fuses (J)

Fault codes and symptom→remedy steps extracted from this model’s service/owner documentation; verify against the official manual before servicing.

Parts

2
Part #DescriptionQtySystem
WP2.02-inch water pump1Pump PartsGeek
WP3.03-inch water pump1Pump PartsGeek

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
Prime50%

Available documents

Brochure — GSA Product List (Kohler)Brochure — PowEquip TriFold English (Kohler)Brochure — portable chart (Kohler)Brochure — tri-fuel accessory launch uspec update (Kohler)Owner's manual — 34 590 01 (Kohler)Service manual — 34 690 01 (Kohler)