The Cummins/Onan GTA8.3 G1 is a 8.3 L 6-cylinder natural gas engine rated at 1500 rpm, producing up to 165 kW. It powers generator sets from Cummins/Onan, including the GGKB and GTA8.3-G1.
Also known as: Cummins GTA8.3 G1
Part of the Cummins/Onan GTA8.3 engine family — 3 variants share parts & fitment.
| Displacement | 8.3 L |
|---|---|
| Cylinders | 6 |
| Aspiration | Natural Gas |
| Rated speed | 1500 rpm |
| Gross power | 165 kW |
How to read your Cummins/Onan engine serial & model number →
Compiled from service & troubleshooting documentation across every generator set that uses the Cummins/Onan GTA8.3 G1.
| Item | Spec | Capacity | Part # | Interval | |
|---|---|---|---|---|---|
| Air filter | — | ||||
| Fuel filter | — | ||||
| Oil filter | — | ||||
| Belt | — | ||||
| Coolant | — | ||||
| Coolant filter | — | ||||
| Oil | — | ||||
| Spark plug | — |
Pooled from every document that names this exact engine — confirm the interval and part number against your unit's serial number.
| Type | Item | Value | Unit | Condition |
|---|---|---|---|---|
| Pressure | SAE J1349 test condition: barometric pressure | 29.61 | in. Hg | 100 kPa; 300 ft (91 m) altitude |
| Pressure | SAE J1349 test condition: water pressure | 0.30 | in. Hg | 1 kPa |
| Temperature | Rating note (1): water temperature to aftercooler, or use of air-to-air aftercooler with 100 F or lower air temperature to the radiator | 32 | C (90 F) | applies to 10.5:1 / 10:1 / 11:1 note-(1) ratings |
| Temperature | Rating note (2): water temperature to aftercooler, or use of air-to-air aftercooler with 130 F or lower air temperature to the radiator | 54 | C (130 F) | applies to 8.5:1 note-(2) ratings |
| Temperature | Rating note (3): water temperature to aftercooler, or use of air-to-air aftercooler with 110 F or lower air temperature to the radiator | 32 | C (90 F) | applies to 10.5:1 note-(3) ratings |
| Temperature | Rating note (4): water temperature to aftercooler, or use of air-to-air aftercooler with 130 F or lower air temperature to the radiator | 54 | C (130 F) | applies to 8.5:1 note-(4) ratings |
| Temperature | SAE J1349 test condition: inlet air temperature | 77 | F | 25 C |
Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.
| Fluid | Grade | Standard | Ambient | Capacity | Notes |
|---|---|---|---|---|---|
| Fuel | dry processed natural gas | 905 BTU per standard cubic foot (33.72 kJ/l) lower heating value, used for the tabulated ratings; deration may be required due to altitude, temperature, type of fuel or use of a catalytic converter |
Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.
| Part # | Description | Category |
|---|---|---|
| 100-025-001 | Air Filter | air_filter |
| 100-029-001 | AIR FILTER | air_filter |
| 100-028-001 | Coolant Filter | belt |
| V2-78 | 400 VF (Vari-Fuel) Bullet Valve | bullet_valve |
| WF2071 | Coolant Filter | coolant_filter |
| WF2072 | Coolant Filter | coolant_filter |
| WF2073 | Coolant Filter | coolant_filter |
| WF2074 | Coolant | coolant_filter |
| WF2070 | Coolant Filter | filter |
| WF2075 | DCA4™ Filter(s) | filter |
| WF2076 | Coolant | filter |
| 525-0301 | Sealant, Thread (6 ml Tube) | fluid |
| 155-3219 | Gasket, Muffler | gasket |
| 502-0942 | Elbow - 90 ° | hose |
| 502-0943 | Connector, Hose (3/8 x 5/8) - GGKB, GGKC | hose |
| 503-0098 | Hose, Oil Drain - Bulk (Order By The Foot - 3 Feet Required) | hose |
| 503-0183 | Clamp, Hose | hose |
| 503-0197 | Clip, Hose | hose |
| 503-0386 | Bulk Hose (water jacket heater; order 15 in. and 6 in. lengths) | hose |
| 518-0548-02 | Clamp, Hose | hose |
| 100-026-001 | Filling valve (optional: without filling hoses) | oil_filter |
| 100-027-001 | Concentric suction/pressure valve (optional: without filling hoses) | oil_filter |
| 100-030-001 | Oil Filter | oil_filter |
| 309-0159 | Switch, Oil Pressure (S107) | oil_filter |
| 3375048 | Oil Filter Wrench. | oil_filter |
| 10113858 | Op Meter Carrying Case. | other_service |
| 102-1448-02 | Adapter, Oil Drain (M10 x 16) | other_service |
| 155-2062-13 | Cap, Rain | other_service |
| 155-2305 | Clamp, Muffler | other_service |
| 155-2570 | Clamp, V-Band A299 | other_service |
| 155-3150-02 | Muffler | other_service |
| 155-3163-01 | Adapter, Exhaust | other_service |
| 155-3164-03 | Pipe, Exhaust | other_service |
| 155-3180 | Shield, Rain | other_service |
| 332-2634 | Clamp, Retainer 4 Prior To December 1996 Production (Mounted On Top And Side Of Control Box Wrapper) | other_service |
| 332-3196 | Clamp, J | other_service |
| 3375208 | DCA4™ Test Kit. | other_service |
| 3394430 | GTA8.3 Irrigation Panel Assy. (5 Gauge Panel) | other_service |
| 3395077 | Digital Thermometer 450 AET Type E. | other_service |
| 416-0619 | Cable, Battery | other_service |
| 416-1000 | Cable, Battery | other_service |
| 504-0011 | Valve, Shutoff (1/2”) | other_service |
| 505-0050 | Elbow, Street (1/2' x 90 ° ) | other_service |
| 505-0057 | Plug, Square Head (1/8') | other_service |
| 505-0185 | Nipple, Half (1/2' x 1.5' lg) | other_service |
| 525-0304 | Onan Green Enamel (Non-Metallic) - Gallon Can | other_service |
| 525-0305 | 12 oz. Pressurized Spray Can | other_service |
| 525-0306 | Onan Green Enamel (Non-Metallic) - Quart Can | other_service |
| 526-2140 | Washer, Flat (M12) | other_service |
| 60110001 | Compression Tester. | other_service |
| 60210006 | Pliers for Ignition Wire Crimping. | other_service |
| 60810002 | Set of Feeler Gauges. | other_service |
| 61210002 | Tachometer Hand Held. | other_service |
| 800-2058 | Screw, Cap - Hex Head (M8 x 1.25 x 25) | other_service |
| 800-2111 | Screw, Cap - Hex Head (M12 x 1.25 x 25mm) | other_service |
| 821-6003-02 | Screw, Cap - Hex Head | other_service |
| 850-2008 | Washer, Lock (M8) | other_service |
| 856-0013 | Washer, Lock - W/EIT (1/2) | other_service |
| 91372621 | Oo Meter. | other_service |
| 91400202 | Carrying Case Digital Manometer (Each) | other_service |
| 91400203 | Digital Manometer 0 to 30 psi. | other_service |
| 91400204 | Digital Manometer 0 to 19.99 WC. | other_service |
| 91400205 | Hand Held Digital Thermometer with Case. | other_service |
| 91400206 | Laser Heat Gun & Carrying Case. | other_service |
| 91400207 | Volt Meter & Hertz Meter. | other_service |
| 91400208 | Timing Light | other_service |
| 91400210 | Carrying Case Small. | other_service |
| 91400211 | Digital Manometer 0 to 199.9 WC. | other_service |
| 91400809 | Carrying Case Large. | other_service |
| 971400039 | Fitting 1/8 npt Thermocouple ( Each). | other_service |
| 193-0432 | Sender, Oil Temperature (S2 Engine Block, E4 Oil Pan) | sensor |
| 309-0269 | Switch, Low Engine Temperature (S4) | sensor |
| 3395076 | Spark Plug Removal 5/8”. | spark_plug |
| S971KA | Snap-On P.N. S971KA magnetic spark plug socket | spark_plug |
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 GTA8.3 G1 has a displacement of 8.3 liters with 6 cylinders.
The Cummins/Onan GTA8.3 G1 powers 2 generator set(s), including Cummins/Onan GGKB, Cummins/Onan GTA8.3-G1.
A commonly reported issue on generators using the Cummins/Onan GTA8.3 G1 is: Warning lamp lights. MESSAGE: OVERLOAD. Fix: Contact an authorized service center..