Specifications
| Fuel | Gasoline |
|---|---|
| Frequency | 60.0 Hz |
| Standby power | 4000 kW |
| Prime power | 4000 kW |
| Controller | A1, Microprocessor Regulated |
| Oil capacity | 1.5 L |
| Voltage options | 120 V, 220 V |
| Phase | 1 |
| Rated current | [33.3, 16.4] A |
| Battery cranking | [360, 450] CCA |
| Battery voltage | 12 V |
| Battery quantity | 1 |
| Dry weight | 84 kg |
Maintenance & consumables
for the Cummins/Onan Onan| Item | Spec | Capacity | Part # | Interval | |
|---|---|---|---|---|---|
| Oil | SAE 10W30 | — | 25 hr |
Common questions
What is the power rating of the Cummins/Onan 4MKY?
The Cummins/Onan 4MKY is rated 4000 kW standby.
What engine does the Cummins/Onan 4MKY use?
The Cummins/Onan 4MKY is powered by the Cummins/Onan Onan engine.
What fuel does the Cummins/Onan 4MKY use?
The Cummins/Onan 4MKY runs on Gasoline.
What is the oil capacity of the Cummins/Onan 4MKY?
The Cummins/Onan Onan engine in the Cummins/Onan 4MKY has an oil capacity of 1.5 liters.
Troubleshooting
27Fault codes
| Code | Meaning | Remedy |
|---|---|---|
| 3 | SERVICE CHECK FAULT—CODE NO. 3 | Check the second-level fault code by pressing STOP once. The second-level fault code will have two-digits. The faults are listed in numerical order in this table. |
| 4 | OVERCRANK FAULT—CODE NO. 4 | 1. Check and fill the fuel tank, as necessary. (Note: The genset fuel pickup is probably higher than the boat engine pickup.) 2. Prime the engine fuel system by holding the control switch at Stop/Prime for 30 seconds. 3. Open any closed fuel valves. 4. Secure the spark plug lead on the spark plug (Page 20). 5. Replace the spark plug (Page 20). 6. Service the air cleaner (Page 19). |
| 12 | OVERVOLTAGE FAULT—CODE NO. 12 | See an authorized Onan dealer. |
| 13 | UNDERVOLTAGE FAULT—CODE NO. 13 | Reduce the number of connected appliances, especially when air conditioners and battery chargers are running. |
| 14 | OVERFREQUENCY FAULT—CODE NO. 14 | See an authorized Onan dealer. |
| 15 | UNDERFREQUENCY FAULT—CODE NO. 15 | Reduce the number of connected appliances, especially when air conditioners and battery chargers are running. |
| 27 | VOLTAGE SENSE FAULT—CODE NO. 27 | See an authorized Onan dealer. |
| 29 | HIGH BATTERY VOLTAGE FAULT—CODE NO. 29 | 1. Check battery bank connections and reconnect if necessary so that the 12 volt batteries serving the genset are connected in parallel (12 v |
| CODE NO. 32 | LOW CRANKING SPEED FAULT—Cranking speed less than 180 rpm for more than 2 seconds | 1. Clean and tighten the positive (+) and negative (−) battery cable connections at the battery and at the genset. 2. Recharge or replace the battery. Refer to the battery manufacturer’s recommendations. 3. Replace engine oil with oil of proper viscosity for ambient temperatures (Page 7). (High oil viscosity can slow down cranking speed.) |
| CODE NO. 35 | CONTROL CARD FAILURE FAULT—Microprocessor EEPROM error during self-test | See an authorized Onan dealer. |
| CODE NO. 36 | ENGINE STOPPED FAULT—Engine stopped without command by controller | 1. Check and fill the fuel tank, as necessary. (Note: The genset fuel pickup is probably higher than the boat engine pickup.) 2. Secure the spark plug lead on the spark plug (Page 20). 3. Replace the spark plug (Page 20). 4. Service the air cleaner (Page 19). 5. Check for mechanical damage. |
| CODE NO. 37 | INVALID GENSET CONFIGURATION FAULT—Genset configuration is preprogrammed at the factory | See an authorized Onan dealer. |
| CODE NO. 38 | OVERCURRENT FAULT—Low power factor loads | 1. Reduce the number of appliances running at the same time, especially those with high motor starting loads such as air conditioners. 2. Have air conditioners and other appliances checked for proper operation. (A locked compressor rotor can cause very low power factor.) |
| CODE NO. 41 | GENERATOR ROTOR FAULT—Controller unable to sense field or output voltage | See an authorized Onan dealer. |
| CODE NO. 42 | PROCESSOR FAULT—Microprocessor ROM error during self-test | See an authorized Onan dealer. |
| CODE NO. 43 | PROCESSOR FAULT—Microprocessor RAM error during self-test | See an authorized Onan dealer. |
| CODE NO. 45 | SPEED SENSE FAULT—Controller unable to sense quadrature frequency | See an authorized Onan dealer. |
| CODE NO. 47 | IGNITION FAULT—Controller unable to sense ignition | See an authorized Onan dealer. |
| CODE NO. 48 | GENERATOR FIELD SENSE FAULT—Controller unable to sense field voltage | See an authorized Onan dealer. |
Symptoms & remedies
| Symptom | Remedy |
|---|---|
| The engine fails to crank. | A. Try starting at the genset rather than at the remote control. b. Replace the fuse on the control panel if it has blown. c. Clean and tighten the positive (+) and negative (- ) battery cable connections at the battery and the genset. d. Recharge the battery. Refer to the battery manufacturer’s recommendations. |
| The engine cranks slowly. | A. Disconnect the air conditioner and other large loads. b. Clean and tighten the positive (+) and negative (- ) battery cable connections at the battery and the genset. c. Recharge the battery. Refer to the battery manufacturer’s recommendations. d. Change the engine oil to oil having the proper viscosity for the ambient temperature. See Table 1. |
| The engine cranks but fails to start. | A. Check the fuel tank and fill if necessary. b. Open any closed fuel shut off valve. c. Check engine oil level and add oil as necessary. d. Service the air cleaner. e. Secure the spark plug lead on the spark plug. f. Replace the spark plug. |
| The engine runs and then stops or surges. | A. Check the fuel tank and fill if necessary. b. Check the engine oil level and add oil as necessary. Drain excess oil if the level is above the dipstick Full mark. c. Check and reset the carburetor altitude adjust knob. See Varying Operating Conditions. (Gasoline models only.) d. Secure the spark plug lead on the spark plug. e. Replace the spark plug. |
| The genset keeps stalling or the circuit breaker keeps tripping. | Try running with fewer appliances connected. See Powering Equipment. |
| There is no electrical power even though the genset runs. | A. Reset tripped circuit breakers. See Powering Equipment. b. Unless there is an automatic power transfer switch, plug the boat power cord into the genset power output receptacle (if so equipped) or turn the boat power selector switch to its genset position (if so equipped). |
| The remote battery condition meter indicates low voltage. | A. Clean and tighten the positive (+) and negative (- ) battery cable connections at the battery and the genset. b. Recharge the battery. Refer to the battery manufacturer’s recommendations. |
| Black smoke exits the tailpipe. | Service the air cleaner. |
Fault codes and symptom→remedy steps extracted from this model’s service/owner documentation; verify against the official manual before servicing.
Repair guides
13- CONNECTORS P5 & P6
- Install the rotor through bolt and washer. Verify
- Remove the fan (Steps 1 through 9, p. 7-3). In-
- Remove the fan (Steps 1 through 9, p. 7-3). In-
- CONNECTOR
- Inspection
- Service Procedure
- Service Procedure
- Service Procedure
- Service Procedure
- Service Procedure
- Service Procedure
- Service Procedure
Step-by-step procedures compiled from the Cummins/Onan service manual for this model.
Parts
8| Part # | Description | Qty | System | |
|---|---|---|---|---|
| A058U956 | P4500i / P4500iDF Maintenance Kit | Maintenance kit | buy | |
| A058U960 | P4500i / P4500iDF Air Filter Element | Air filter element | buy | |
| A058V025 | Bougie d'allumage | Spark plug | Amazon eBay | |
| 0500-3298 | OUTLINE DRAWING | Service part / kit | buy | |
| 0611-1268-2 | RECONNECTION DIAGRAMS | Service part / kit | buy | |
| A058U958 | P4500i/P4500iDF Key Fob | Service part / kit | buy | |
| A058V024 | High Altitude Carburetor Kit | Service part / kit | buy | |
| A073Z778 | P4500iDF/P5000iDF EFI High Altitude Propane Regulator Kit | Service part / kit | buy |
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 | 2.7 | 0.71 | |
| Full_load | 100% | 2.7 | 1.0 |
| Half load | 1.8 | 0.48 | |
| Half_load | 50% | 1.4 | 0.5 |
| No load | 1.1 | 0.29 | |
| No_load | 0.79 | 0.3 | |
| Prime | |||
| Prime | 50% | 1.8 | 0.48 |
| Prime | 100% | 2.7 | 0.71 |
| Standby | |||
| Standby | 1.1 | 0.29 |
Available documents
Operator's manual — 981-0160 Onan MKY Pontoon Operator's Manual (12-2003)Service manual — 981-0531 Onan MKY Spec J Pontoon Service Manual (8-1999) (Cummins/Onan)Service manual — 981-0618 Onan MKY Pontoon Installation Manual (12-2003) (Cummins/Onan)Service manual — 981-0622 Onan MKY Installation Manual (3-2009) (Cummins/Onan)Service manual — 981-0622B Onan MKY Pontoon Install Manual (12-2003) (Cummins/Onan)