Specifications
| Standby power | 200 kW |
|---|---|
| Oil capacity | 40.0 L |
Engine
| Oil capacity | 40.0 L |
|---|---|
| Coolant capacity | 51.0 L |
| Displacement | 8.55 L |
| Aspiration | turbocharged |
| Rated speed | 1800 rpm |
Filters for the Cummins/Onan NT855
8Engine-mounted filters the filter manufacturers list for this engine family. These come from the engine, not from this generator set’s own parts list, so confirm against your serial number before ordering.
| System | Filter | Description | Cross-references | |
|---|---|---|---|---|
| Oil filter | P551670 | Lube Filter, Spin-On Full Flow | CUMMINS 298670, CUMMINS 299670, NAPA 1970, CARBOCOL 0026 | FridayParts $26.68 |
| Oil filter | P550777 | Lube Filter, Spin-On Bypass | CUMMINS 3021658, CUMMINS 33004232, NAPA 1749, BALDWIN B7577 | FridayParts $43.56 |
| Fuel filter | P550105 | Fuel Filter, Spin-On Primary | CUMMINS 154700, CUMMINS 154710, NAPA 3109, NAPA 3405 | buy |
| Fuel filter | P557440 | Fuel Filter, Spin-On Secondary | CUMMINS BM78672, BALDWIN BF970, LPM 00013505994, WALGAHN-MOTORENTECHN 00811464 | FridayParts $189.69 |
| Fuel / water separator | P550106 | Fuel Filter, Water Separator Spin-On | CUMMINS 154789, CUMMINS 156164, NAPA 3405, BALDWIN BF957-D | FridayParts $285.60 |
| Fuel / water separator | P558000 | Fuel Filter, Water Separator Spin-On Twist&Drain | CUMMINS 3308638, CUMMINS 3308683, NAPA 3405, NAPA 3693 | KuduParts $24.00 FridayParts $25.66 |
| Coolant filter | P554071 | Coolant Filter, Spin-On | CUMMINS 209604, CUMMINS 209606, NAPA 4071, WALGAHN-MOTORENTECHN 00811412 | FridayParts $397.60 |
| Coolant filter | P554073 | Coolant Filter, Spin-On | CUMMINS 209605, CUMMINS 209607, NAPA 4073, VERSATILE 00104040 | KuduParts $40.00 |
Maintenance & consumables
for the Cummins/Onan NT855| Item | Spec | Capacity | Part # | Interval | |
|---|---|---|---|---|---|
| Air filter | If the engine is equipped with an oil bath type air cleaner, fill to the level indicated with oil of the same viscosity as used in the crankcase. However, a non-detergent (straight mineral) oil is recommended. | — | 1000 hr | ||
| Fuel filter | — | 500 hr | |||
| Oil filter | — | 1000 hr | |||
| Battery | Batteries will self discharge very quickly when installed where the ambient temperature is consistently above 90°F, such as in a boiler room. To lengthen battery life dilute the electrolyte from its normal 1.275 specific gravity reading at full charge to a 1.225 reading. | — | 1440 hr | ||
| Belt | — | 1000 hr | |||
| Coolant | For units which use either a radiator or heat exchanger (city water cooled), fill the cooling system with clean soft water, The standard radiator and block capacity is 21 U.S. gallons. Use a good rust and scale inhibitor. If there is any possibility of a radiator cooled plant being exposed to freezing temperatures, use antifreeze with ethylene glycol base as instructed in the Cummins manual. | 80.63 L | — | 5000 hr | |
| Coolant filter | Refer to Cummins engine Operation and Maintenance Manual. | — | |||
| Oil | 7.0 L | — | 100 hr | ||
| Spark plug | — | 1000 hr |
Common questions
What size generator is the Cummins/Onan NT 855?
The Cummins/Onan NT 855 is rated 200 kW standby.
What engine is in the Cummins/Onan NT 855?
The Cummins/Onan NT 855 is powered by the Cummins/Onan NT855 engine.
How much oil does the Cummins/Onan NT 855 take?
The Cummins/Onan NT855 engine in the Cummins/Onan NT 855 has an oil capacity of 40.0 liters.
What is the cooling system capacity of the Cummins/Onan NT 855?
The Cummins/Onan NT 855 cooling system holds 51 liters (13.5 US gallons) for the engine, per the manufacturer specification sheet.
Troubleshooting
6Symptoms & remedies
| Symptom | Cause | Remedy |
|---|---|---|
| Air Induced into the Cooling System | Defective Fan or Shutter Control Valves | Refer to Procedure 1-11 |
| Engine Overheating | Refer to ‘‘Coolant Temperature Above Normal’’ Symptom Chart on page 3 | |
| FUEL IN COOLANT | Fuel Heater Malfunctioning | Replace the fuel heater. Refer to the equipment manufacturer’s recommendations |
| LOW LUBRICATING OIL PRESSURE | Incorrect Oil Level | Check for oil leaks. Add or drain engine oil. Refer to Procedures 2-09 and 2-10. Check dipstick calibration. Refer to Procedure 2-14 |
| LUBRICATING OR HYDRAULIC OIL IN THE COOLANT | Lubricating Oil Cooler Malfunctioning, Hydraulic Oil Cooler Malfunctioning, Cylinder Head Gasket Leakage, Cylinder Head Cracked or Porous, Cylinder Block Cracked or Porous | Inspect oil cooler. Refer to Procedure 2-20. Inspect hydraulic oil cooler. Refer to manufacturer’s specifications. Replace cylinder head gasket. Refer to Procedure 7-11. Inspect ylidner head. Refer to procedure 7-12. Inspect cylinder block. Refer to Procedure 1-12 |
| Locate the symptom on the list. | Starting at the top with the simplest |
Fault codes and symptom→remedy steps extracted from this model’s service/owner documentation; verify against the official manual before servicing.
Parts
77| Part # | Description | Qty | System | |
|---|---|---|---|---|
| 0300-4623-08 | DFBF (600V) | 1 | Current transformer | Amazon eBay |
| 0300-4623-23 | DFBF BR (0-480V) | 1 | Current transformer | Amazon eBay |
| 193-0432 | Sender, Oil Temperature (S2 Engine Block, E4 Oil Pan) | 2 | Sensor | Amazon eBay |
| 1S0A713 | Bracket, Overspeed Switch | 1 | Bracket | Amazon eBay |
| 1S0A717 | Switch Assy., Overspeed | 1 | Switch | Amazon eBay |
| 204493 | Ring, Collector | 1 | Ring | Amazon eBay FridayParts $27.10 |
| 2110153 | Bell, End - Alt, to Exciter | 1 | Bell | Amazon eBay |
| 23201396 | Support, Gen. Mtg. | 1 | Support | Amazon eBay |
| 232A1817 | Generator | 3 | Generator | Amazon eBay |
| 2340116 | Cover, Exciter | 1 | Cover | Amazon eBay |
| 234070 | Rig Assy., Brush- Incl. Brushes, & Contact Point Band, Gen. - Front Portion(Narrow) | 1 | Brush | Amazon eBay |
| 2348115 | Bracket, Mtg. - Volt. Cont. Reactor | 1 | Bracket | Amazon eBay |
| 234875 | Bracket, Gate Reactor Mtg. | 1 | Bracket | Amazon eBay |
| 234C134 | 3-Phase | 1 | Phase | Amazon eBay |
| 234C137 | 3-Phase | 1 | Phase | Amazon eBay |
| 234C140 | Single Phase | 1 | Phase | Amazon eBay |
| 234C141 | Single Phase | 1 | Phase | Amazon eBay |
| 2I4AM | Brush | 4 | Brush | Amazon eBay |
| 302P421 | Scale Reads 0-300 | 1 | Voltmeter | Amazon eBay $240.00 |
| 302P465 | RESISTOR-STABILIZING | 1 | Meter | Amazon eBay |
| 302P466 | For 220/380-V, 3-Ph, 60-Cycle (Model H) | 1 | Meter | Amazon eBay |
| 302P468 | For 120/208-V,120/240-V, & 347/600-V 3PH. 50 Cy!. (825-Ohm, 75-Watt) | 1 | Meter | Amazon eBay |
| 302P469 | For 220/380-V, 3Ph. 50-Cycle | 1 | Meter | Amazon eBay |
| 302P470 | For 277/480-V, 3-Ph, 50-Cyclo (5-P!) | 1 | Meter | Amazon eBay |
| 3044125 | 15,000-Ohm, 25-W - For 220/380-V, 3-Phase, 4-Wire | 1 | Resistor | Amazon eBay |
| 304A15 | S Washer, Fixed Resistor Cent. to Alternator End Bell | 1 | Washer | Amazon eBay |
| 304PA76 | Resistor, Volt. Cont.Reactor (Incl.in Rect.& Resistor A: 305P218) | 1 | Resistor | Amazon eBay |
| 3058227 | Resistor Assy., Rect, & Incl. (Incl.in Rect. & Resistor A: 305P218) | 4 | Resistor | Amazon eBay |
| 305P233 | Rectifier Only, Power (Field) - Lower two - Negative (Begin Spec 'C' included in Rectifier & Reactor Assembly #305B227) | 2 | Rectifier | Amazon eBay |
| 305P234 | Rectifier Assy., Power (Field) (Incl. in Rect. #305P218) | 2 | Rectifier | Amazon eBay |
| 305P240 | Rectifier, Volt. Cont.Reactor (Incl.in Rect. & Resistor A: 305P218) | 4 | Rectifier | Amazon eBay |
| 309-0269 | Sender, Temperature-Lo Engine | 1 | Sensor | Amazon eBay $239.00 |
| 319-2236 | Bracket, Mounting | 1 | Bracket | Amazon eBay |
| 3320645 | Strip, Marker - Volt. Con. Reactor (9305P218) | 1 | Strip | Amazon eBay |
| 3ISA78 | Rectifier, Voltage Control | 1 | Rectifier | Amazon eBay |
| 508-0292 | Washer, Sealing - Copper | 1 | Seal | Amazon eBay |
| 518-0548-58 | Clamp, Hose | 3 | Clamp | Amazon eBay |
| 5208190 | Stud, Fixed Resistor Mtg. | 1 | Stud | Amazon eBay |
| 805-35 | Bolt, Place - Generator Mtg. Support to End Bell | 4 | Bolt | Amazon eBay |
| 960-0504 | PCC Control Service Manual | * | Service manual | Amazon eBay |
| 960-0507 | Detector Control Service Manual | ** | Service manual | Amazon eBay $49.00 |
| A956 | 2-12 VOLT BATTERIES | 2 | Battery | Amazon eBay |
| 102-1335 | Plug, Oil Drain | 1 | Service part / kit | Amazon eBay |
| 232A1489 | Generator support shim, 0.598 in gauge #6, 3x3 | 2 | Service part / kit | Amazon eBay |
| 232A1490 | Generator support shim, 0.359 in gauge #20, 3x3 | 2 | Service part / kit | Amazon eBay |
| 301021151 | Box Only, control | 1 | Service part / kit | Amazon eBay |
| 30118301 | Bracket, Cont.Box Mtg. (Repl. 2-Piece Brkts) | 1 | Service part / kit | Amazon eBay |
| 301A1914 | Bracket, Panel Stop | 1 | Service part / kit | Amazon eBay |
| 301A2727 | Handle , Control Box | 1 | Service part / kit | Amazon eBay |
| 302-213 | 60-Cycle | 1 | Service part / kit | Amazon eBay |
| 302-234 | .Cycle | 1 | Service part / kit | Amazon eBay |
| 3028448 | Plate, Mater Face | 1 | Service part / kit | Amazon eBay $74.95 |
| 302P411 | ~~ Scale Reads 0-200 (1-Phase Use 2) | 1 | Service part / kit | Amazon eBay |
| 302P412 | Scale Reads 0-250 | 1 | Service part / kit | Amazon eBay |
| 302P414 | Amm, Scale Reads 0-300 - Replaces 302-14. | 1 | Service part / kit | Amazon eBay |
| 302P415 | Ammeter Scale Reads 0-500 - Replaces 302-371. | 1 | Service part / kit | Amazon eBay |
| 302P422 | Scale Reads 0-600 | 1 | Service part / kit | Amazon eBay |
| 302P423 | Scale Reads 0-750 on side of Gen | 1 | Service part / kit | Amazon eBay |
| 302P467 | For 277/480 Volt,3 Phase, 60 Cycle Plants. | 1 | Service part / kit | Amazon eBay |
| 303-111 | Rheostat, Volt. Reg. - 175-Ohm, (Model H) | 1 | Service part / kit | Amazon eBay |
| 303-32 | Knob, Rheos | 1 | Service part / kit | Amazon eBay |
| 3040305 | 45, 000-Ohm, 10-W - For 480-V , 3-Ph, 3-Wire & 277/480-V, 3+ Ph. | 1 | Service part / kit | Amazon eBay |
| 307-2621-02 | Relay, Start Solenoid (K4) | 1 | Service part / kit | Amazon eBay |
| 308-22 | Switch, Volt. & Current Selector Ammeter | 1 | Service part / kit | Amazon eBay FridayParts $47.99 |
| 32082 | 3-Phase Models | 1 | Service part / kit | Amazon eBay |
| 320B18 | Single Phase Models | 1 | Service part / kit | Amazon eBay |
| 337A44 | Strap, Ground | 1 | Service part / kit | Amazon eBay |
| 402-78 | Rubber, Mtg. - Cont. Box | 4 | Service part / kit | Amazon eBay |
| 504-0011 | Valve, Shutoff (1/2”) | 1 | Service part / kit | Amazon eBay $59.95 |
| 505-0019 | Bushing, Pipe - Reducer 1/2” to 3/8”, DFBF (1/2” to 3/8”) 505-0131 DFCB, DFCC, DFCE (3/4” to 3/8”) | 1 | Service part / kit | Amazon eBay |
| 505-0100 | Nipple, Pipe - Close (1/2”) | 1 | Service part / kit | Amazon eBay $9.34 |
| 526-0029 | *Washer, Flat (1/2") | 1 | Service part / kit | Amazon eBay |
| 526-0219 | Washer, Flat (1/2) | 2 | Service part / kit | Amazon eBay |
| 800-0048 | Screw, Cap - Hex Head (3/8-16 x 3/4”) | 1 | Service part / kit | Amazon eBay |
| 800-0092 | Screw, Cap - Hex Head (1/2-13 x 1.5) | 4 | Service part / kit | Amazon eBay |
| 850-0050 | Washer, Lock - Spring (3/8”) | 2 | Service part / kit | Amazon eBay |
| 870-0212 | Nut, Locking (1/4-20) | 2 | 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 — NT855 60HZ 281~350kw (Cummins/Onan)Parts manual — 960-0236 Onan DFBE NT5 Parts Manual (2-1990) (Cummins/Onan)Parts manual — 960-0238 Onan DFCB NTA2 Parts Manual (2-1990) (Cummins/Onan)Parts manual — 960-0248 Onan DFEB KTA12 Parts Manual (12-1989) (Cummins/Onan)Parts manual — 960-0249 Onan DFJA KTA31 Parts Manual (12-1989) (Cummins/Onan)Parts manual — 960-0250 Onan DFJB KTA32 Parts Manual (12-1989) (Cummins/Onan)Parts manual — 960-0252 Onan DFFA KTT11 Parts Manual (12-1989) (Cummins/Onan)Service manual — cummins-n855-big-cam-3-and-4-workshop.manual-693p-abby (Cummins/Onan)
This page was generated from the 8 manufacturer documents above by automated extraction; every figure shown is copied from one of them. How the data is compiled.