The Cummins/Onan KTA50 series is a 50 L 16-cylinder turbocharged and after-cooled engine rated at 50 rpm, producing up to 50 kW. It powers generator sets from AKSA and Cummins/Onan, including the AC1435, AC1675, C1250 D6 and C1400 D5. It holds 44.7 L (11.8 gal) of oil and 348 L (91.9 gal) of coolant.
Also known as: Cummins KTA50 series
Part of the Cummins/Onan KTA50 engine family — 12 variants share parts & fitment.
| Oil capacity | 44.7 L |
|---|---|
| Coolant capacity | 348.0 L |
| Displacement | 50.0 L |
| Cylinders | 16 |
| Aspiration | turbocharged and after-cooled |
| Rated speed | 50 rpm |
| Gross power | 50 kW |
Shared across brands: AKSA, Cummins/Onan
Compiled from service & troubleshooting documentation across every generator set that uses the Cummins/Onan KTA50 series.
| Item | Spec | Capacity | Part # | Interval | |
|---|---|---|---|---|---|
| Air filter | Dry replaceable element | — | 3600 hr | find | |
| Fuel filter | FS1006 | Amazon eBay $39.99 PartsGeek | |||
| Oil filter | Cummins OE | F450-100 | 3600 hr | PartsGeek | |
| Belt | — | find | |||
| Coolant | 50/50 Ethylene Glycol and Water | 12.7 L | — | 3600 hr | |
| Oil | 5W-40 | 160.0 L | — | 3600 hr |
Pooled from every document that names this exact engine — confirm the interval and part number against your unit's serial number.
| Part # | Description | Category |
|---|---|---|
| 140-2096 | Element, Primary (Outer) | air_filter |
| 140-2467 | Element, Safety (Inner) | air_filter |
| 140-2501 | Cleaner, Air (Disposable) | air_filter |
| 140-2502 | Band, Mounting – Air Cleaner | air_filter |
| 140-2503 | Bracket, Mounting | air_filter |
| 140-3163 | Cleaner, Air (No Replaceable Element) | air_filter |
| 140-3230 | Cleaner, Air (Includes Elements - See Ref. No. 25 and 26) | air_filter |
| 0300-4623-29 | DFLB (600V) | current_transformer |
| 0300-4623-33 | DFLE (600V) | current_transformer |
| 0300-4623-52 | DFLB BR (0-480V) | current_transformer |
| 0300-4623-57 | DFLE BR (0-480V) | current_transformer |
| 159-1445 | Reservoir, Fuel | fluid |
| FS1216 | Fuel/Water Sep Spin-On | fuel_filter |
| 121-0113 | Gasket, Pump | gasket |
| 121-0117 | Gasket, Hand Hole | gasket |
| 128-0108 | Insulation, Hose – Bulk (Order By The Foot – 12 Feet Required) | hose |
| 130-5588-02 | Tube, Water Heater | hose |
| 130-5589-02 | Tube, Water Heater | hose |
| 130-5590-02 | Tube, Water Heater | hose |
| 130-5591-02 | Tube, Water Heater | hose |
| 501-0704 | Line, Flexible Fuel - Fuel Out | hose |
| 501-0707 | Line, Flexible Fuel - Fuel In | hose |
| 502-1162 | Connector, Hose (3/8") | hose |
| 503-0685 | Clamp, Hose | hose |
| 503-1484 | Elbow, Hose (45 Deg) (7" ID) | hose |
| 503-1620 | Hose – Bulk (3/8" ID) (Order by the Foot) | hose |
| 503-1870-11 | Clamp, Hose | hose |
| 503-1870-12 | Clamp, Hose | hose |
| LF3325 | Lube, Full-Flow Spin-On | oil_filter |
| 121-0116 | Cover, Hydraulic Hole | other_service |
| 140-1260 | Fitting, Safety Filter | other_service |
| 140-1548 | Indicator, Service | other_service |
| 140-2097 | Cleaner | other_service |
| 140-2098 | Hood, Air Inlet (Includes Mounting Clamp) | other_service |
| 140-2099 | Band | other_service |
| 140-2395 | Tube, Air Inlet | other_service |
| 140-2504-01 | Bracket - Right Side | other_service |
| 140-2504-02 | Bracket - Left Side | other_service |
| 140-2508 | Tube, Air Inlet (7" x 9" - 3/4") | other_service |
| 140-2509 | Tube, Air Inlet | other_service |
| 140-2515 | Bracket, Mounting | other_service |
| 140-2519 | Tube, Air Inlet | other_service |
| 140-2521 | Tube, Air Inlet | other_service |
| 140-2528 | Shield – Air In Heat | other_service |
| 309-0635-02 | Valve, Check | other_service |
| 332-2634 | Clamp, Retainer 4 Prior To December 1996 Production (Mounted On Top And Side Of Control Box Wrapper) | other_service |
| 333-0677-01 | Heater, Coolant - 4990 Watt | other_service |
| 333-0677-02 | Heater, Coolant - 6420 Watt | other_service |
| 503-1717 | Elbow, Reducer (45 Deg) (7" ID to 6" ID) | other_service |
| 503-1720 | Insert, Reducer (6" OD to 5-1/2" ID) | other_service |
| 505-0017 | Bushing, Pipe – Reducer (3/8" to 1/4") | other_service |
| 505-0376 | Elbow – 45 Deg (3/8") | other_service |
| 518-0548-24 | Clamp, Retainer Begin December 1996 Production (Mounted On Top And Side Of Control Box Wrapper On The Side Towards The Control Box Cover) | other_service |
| 518-0548-42 | Clamp, Retainer 4 Prior To December 1996 Production (Mounted On Top And Side Of Control Box Wrapper) | other_service |
| 526-0030 | Washer, Flat (3/8") | other_service |
| 800-0055 | Screw, Cap – Hex Head (3/8–16 x 2-1/4") | other_service |
| 800-0094 | Screw, Cap – Hex Head (1/2–13 x 2") | other_service |
| 821-0029 | Screw, Self–Locking – Hex Washer Head (3/8–16 x 3/4") | other_service |
| 821-0033 | Screw, Self–Locking – Hex Washer Head (7/16–14 x 3/4") | other_service |
| 821-5004-03 | Screw, Self-Locking – Hex Washer Head (3/8–16 x 1") | other_service |
| 870-0281 | Nut, Self-Locking – Hex Washer Head (3/8–16) | other_service |
| 960-0606 | other_service | |
| 960-0608 | other_service | |
| F-2061 | Installation of two C1400 D5 generator sets | other_service |
| 121-0111 | Drive, Pump | pump |
| 159-1451 | Pump, Fuel Transfer | pump |
| 509-0283-01 | Seal | seal |
| 509-0336 | Seal, O-Ring | seal |
| 509-0337 | Seal, O-Ring | seal |
| 960-0504 | PCC Control Service Manual | service_manual |
| 960-0507 | Detector Control Service Manual | service_manual |
| 309-0649 | Thermostat | thermostat |
Parts cataloged across all variants of this engine family — verify the exact part fits your specific variant and serial number before ordering.
The Cummins/Onan KTA50 series engine has an oil capacity of 44.7 liters.
The Cummins/Onan KTA50 series has a displacement of 50.0 liters with 16 cylinders.
The Cummins/Onan KTA50 series powers 19 generator set(s), including AKSA AC1435, AKSA AC1675, Cummins/Onan C1250 D6, Cummins/Onan C1400 D5, Cummins/Onan C1500 D6.
The Cummins/Onan KTA50 series oil change interval is every 3600 hours.
A commonly reported issue on generators using the Cummins/Onan KTA50 series is: Over Current.