Specifications
| Fuel | gasoline |
|---|---|
| Frequency | 60.0 Hz |
| Standby power | 4 kW |
| Prime power | 4000 kW |
| Controller | Microprocessor Regulated |
| Oil capacity | 1.5 L |
| Voltage options | 120 V, 230 V |
| Phase | 1 |
| Rated current | 33.3 A |
| Battery cranking | 450 CCA |
| Battery voltage | 12 V |
| Dry weight | 79 kg |
| Tank runtime | [0.7, 1.0, 1.5] hr |
Maintenance & consumables
for the Cummins/Onan KYD| Item | Spec | Capacity | Part # | Interval | |
|---|---|---|---|---|---|
| Battery | Installation Review and Startup (Page 20) | — | 150 hr |
Common questions
How many kW is the Cummins/Onan 4KY?
The Cummins/Onan 4KY is rated 4 kW standby.
What engine is in the Cummins/Onan 4KY?
The Cummins/Onan 4KY is powered by the Cummins/Onan KYD engine.
What fuel does the Cummins/Onan 4KY use?
The Cummins/Onan 4KY runs on gasoline.
What's the oil capacity on a Cummins/Onan 4KY?
The Cummins/Onan KYD engine in the Cummins/Onan 4KY has an oil capacity of 1.5 liters.
Troubleshooting
6Symptoms & remedies
| Symptom | Cause | Remedy |
|---|---|---|
| Generator output connections must be made by a qualified electrician | Make generator output connections only by a qualified electrician in accordance with applicable codes. | |
| The genset must not be connected to the public utility or any other source of electrical power. | Do not connect the genset to the public utility or any other source of electrical power. Use an approved switching device to prevent interconnections. | |
| Generator sets use substances that can cause health risks | Use appropriate personal protective equipment when exposed to fuel, oil, coolant, wet batteries, grease, cleaning agents, or other substances. Use proper containers for transport, storage, and disposal of waste substances. Follow local regulations. | |
| STARTING BATTERIES RUN DOWN | (Marginal batteries, connections, or charging system or, parasitic loads) | 1. Clean and tighten the positive (+) and negative (−) battery cable connections at the battery, vehicle frame and genset. 2. Recharge or replace the battery. Refer to the battery manufacturer’s recommendations. 3. Have a battery charging system installed or serviced in the vehicle. |
| STARTER ENGAGES-DISENGAGES | (Cranking voltage dips below 6 volts—low battery charge, poor connections, long cables) | 1. Have the vehicle propulsion engine running while trying to start the genset—the battery charging alternator may be able to maintain starting voltage high enough to get the genset started. 2. Clean and tighten the positive (+) and negative (−) battery cable connections at the battery, vehicle frame and genset. 3. Recharge or replace the battery. Refer to the battery manufacturer’s recommendations. 4. Increase battery cable size or run parallel cables. |
| STATUS INDICATOR LIGHT GOES OUT WHILE CRANKING—NO START | (Internal short circuit caused automatic-reset circuit protective device to trip) | Try starting again. See an authorized Onan dealer if the status indicator light flashes and then goes out again without the engine starting. |
Fault codes and symptom→remedy steps extracted from this model’s service/owner documentation; verify against the official manual before servicing. Full Cummins/Onan 4KY troubleshooting guide (42 entries) →
Parts
8| Part # | Description | Qty | System | |
|---|---|---|---|---|
| 0500-3297-1 | STANDARD RIGID UNDERFLOOR MOUNTING KIT (403-3608) | Service part / kit | Amazon eBay | |
| 0500-3297-2 | UNDERFLOOR BASE KIT (403-3630) | Service part / kit | Amazon eBay | |
| 0500-3297-3 | SOFT UNDERFLOOR MOUNTING KIT (403-3670) | Service part / kit | Amazon eBay | |
| 0611-1268-2 | RECONNECTION DIAGRAMS | Service part / kit | Amazon eBay | |
| 403-3608 | STANDARD RIGID UNDERFLOOR MOUNTING KIT | Service part / kit | Amazon eBay | |
| 403-3630 | UNDERFLOOR BASE KIT | Service part / kit | Amazon eBay | |
| 403-3670 | SOFT UNDERFLOOR MOUNTING KIT | Service part / kit | Amazon eBay | |
| 539-4814 | floor cutout template | 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 |
|---|---|---|---|
| Full load | 0.71 | 2.7 | |
| Half load | 0.48 | 1.8 | |
| No load | 0.29 | 1.1 | |
| Standby | 1.1 | 0.29 | |
| Standby | 50% | 1.8 | 0.48 |
| Standby | 100% | 2.7 | 0.71 |
Available documents
Service manual — 0981-0621 (Cummins/Onan)Service manual — 981-0169B Onan KYD Mobile Genset Operator's manual (11-2004)Service manual — 981-0530C Onan KY (spec J) KYD (spec A) RV Genset Service Manual (01-2006) (Cummins/Onan)Service manual — 981-0621 Onan KY Installation Manual (5-2000)) (Cummins/Onan)Service manual — 981-0636 Onan KYD Mobile Genset Operator's manual w-981-1054 Supplement (12-2005) (Cummins/Onan)Service manual — onan3600manual (Cummins/Onan)