Service parts for the 50ROZ
Grouped by system, with how many of each the parts manual calls for.
Fuel system
1 requiredOil system
1 requiredPrices captured from merchant listings; some links are affiliate links. Confirm against your serial number before ordering.
Specifications
| Fuel | Diesel |
|---|---|
| Frequency | 60.0 Hz |
| Standby power | 55 kW |
| Standby kVA | 69 |
| Prime power | 50 kW |
| Controller | Decision-Maker 1, Decision-Maker 340 |
| Oil capacity | 13.2 L |
| Voltage options | 120/208 V, 120/240 V, 127/220 V, 139/240 V, 220/380 V, 277/480 V, 347/600 V |
| Phase | 3 |
| Rated current | 191 A |
| Power factor | 0.8 |
| Battery cranking | 640 CCA |
| Battery voltage | 12 V |
| Battery quantity | 1 |
| Coolant capacity | 18.0 L |
| Engine jacket water | 7.6 L |
| Max ambient | 50 °C |
| Dimensions (L×W×H) | 2083×737×1093 mm |
| Dry weight | 823 kg |
Engine
| Oil capacity | 13.2 L |
|---|---|
| Coolant capacity | 18.0 L |
| Displacement | 3.92 L |
| Aspiration | Turbocharged |
| Rated speed | 1800 rpm |
Filters for the John Deere 4039T
4Engine-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 | P550020 | Lube Filter, Spin-On Full Flow | JOHN DEERE AR58956, JOHN DEERE AT19044T, NAPA 1243, RENAULT VI 0003132302 | KuduParts $23.00 FridayParts $25.67 |
| Fuel filter | P551130 | Fuel Filter, Box | JOHN DEERE AR50041, JOHN DEERE R16951, NAPA 3370, BALDWIN BF909 | KuduParts $37.00 |
| Fuel / water separator | P551423 | Fuel Filter, Water Separator Spin-On | JOHN DEERE RE503254, JOHN DEERE RE50455, NAPA 3531, NAPA 600091 | KuduParts $18.00 FridayParts $20.00 |
| Fuel / water separator | P551424 | Fuel Filter, Water Separator Spin-On | JOHN DEERE RE503198, JOHN DEERE RE522868, NAPA 3532, NAPA 600094 | KuduParts $16.00 FridayParts $18.50 |
Same engine, other brands
1 brandThe John Deere 4039T in this set also powers 1 generator set sold under 1 other brand. Service parts and maintenance intervals for the engine are shared; enclosure, alternator, controller and ratings are not.
| Brand | Models |
|---|---|
| John Deere | 4039 |
Maintenance & consumables
for the John Deere 4039T| Item | Spec | Capacity | Part # | Interval | |
|---|---|---|---|---|---|
| Fuel filter | Primary | 223414 | Amazon eBay $13.45 NAPA $34.79 | ||
| Oil filter | 229678 | Amazon eBay $24.45 PartsGeek $7.98 NAPA $9.09 |
Service specifications
8| Type | Item | Value | Unit | Condition |
|---|---|---|---|---|
| Clearance | Rotor bearing outer race to end bracket measurement | 1/4 | in. | (6 mm) |
| Gap | Speed sensor air gap | 0.020 | in. | (0.508 mm) |
| Other | Insulation strip length per lead | 1/4 | in. | (6 mm) |
| Other | Photo transistor board lead strip length (gray insulator jacket) | 2-3 | in. | (50-75 mm) |
| Torque | Drive disc mounting bolts | 50 | ft. lbs. | (67.8 Nm) |
| Torque | Fan bolts | 260 | in. lbs. | (29.4 Nm) |
| Torque | Photo transistor board mounting screws | 10 | in. lbs. | maximum (1.1 Nm) |
| Torque | SCR terminal connections | 8 | in. lbs. | maximum (0.9 Nm) |
Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.
Procedures
4Generator Disassembly repair
Tools: hoist, lifting eyes, wood blocks, wrenches
- Disconnect controller-to-engine and engine-to-generator harnesses and wiring.
- Remove bolts from generator vibro-mounts.
- Suspend generator at both ends with hooks in lifting eyes.
- Place wood blocks under flywheel housing; lower generator end onto blocks.
- Remove fan guard; remove bolts holding adapter to flywheel housing.
- Remove nuts and spacers holding drive discs to flywheel.
- Work drive discs over studs to separate generator from engine.
- Set generator on floor horizontally; remove drive discs and fan.
Generator Reassembly repair
Tools: hoist, torque wrench, wrenches
- Install new tolerance ring in end bracket.
- Suspend rotor over generator; lower rotor field into stator.
- Align rotor bearing into end bracket tolerance ring.
- Place fan over rotor flange and torque bolts.
- Fasten drive discs to rotor shaft and torque bolts.
- Attach hoist to end bracket and adapter eye; raise generator horizontally.
- Align studs with drive discs; install spacers; fasten adapter to flywheel housing.
- Install fan guard; replace LED board, speed sensor, junction box, controller; reconnect systems.
Prior to Disassembly repair
⚠ Unit starts without notice; turn Master Switch off and remove battery cables.
⚠ Electrical shock from battery; remove jewelry.
⚠ Hot piping; allow unit to cool.
Tools: battery tools, fuel containers
- Disconnect starting batteries, negative lead first; remove from work area.
- Disconnect AC accessories: battery charger, block heater, fuel transfer pump.
- Shut off fuel supply and drain fuel into proper containers.
- Ventilate work area to clear fumes.
- Disconnect fuel, cooling, and exhaust systems as necessary to tilt generator.
- Disconnect output leads or load circuit cables at generator.
- Check generator weight on nameplate; verify lifting equipment rated.
Rotor Replacement repair
Tools: hoist, lifting eye, screwdriver, wire stripper, crimp tool, torque wrench
- Fasten lifting eye and hoist hook to rotor flange.
- Hoist rotor carefully to avoid damaging exciter field magnets.
- Remove screws securing photo transistor board; retain screws.
- Install new photo transistor board; route lead through rotor shaft.
- Attach board, insulator, washers, and actuator cup with retained screws.
- Cut excess lead; strip gray jacket 2-3 in.; strip 1/4 in. insulation; crimp terminals.
- Secure leads to rotor shaft with tie wrap.
- Connect red to F+ stud, green to G stud, white to AC, black to other AC.
Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.
Voltage reconnection
| Voltage | Phase | Connection | Leads | Notes |
|---|---|---|---|---|
| FR Activator wiring | Red wire to SCR F+ stud; Green wire to G stud; White wire to any AC stud; Black wire to other AC stud | Maximum torque on SCR terminals 8 in. lbs. (0.9 Nm). |
Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.
Common questions
What is the power rating of the Kohler 50ROZ?
The Kohler 50ROZ is rated 55 kW standby (69.0 kVA).
What engine does the Kohler 50ROZ use?
The Kohler 50ROZ is powered by the John Deere 4039T engine.
Is the Kohler 50ROZ diesel or gas?
The Kohler 50ROZ runs on Diesel.
What is the oil capacity of the Kohler 50ROZ?
The John Deere 4039T engine in the Kohler 50ROZ has an oil capacity of 13.2 liters.
What is the coolant capacity of the Kohler 50ROZ?
The Kohler 50ROZ cooling system holds 18 liters (4.8 US gallons) for the radiator system including the engine, per the manufacturer specification sheet.
What is the prime power rating of the Kohler 50ROZ?
The Kohler 50ROZ is rated 50 kW prime (63 kVA), against 55 kW standby.
What is the dry weight of the Kohler 50ROZ?
The Kohler 50ROZ has a dry weight of 823 kg (1814 lb).
What voltage does the Kohler 50ROZ produce?
The Kohler 50ROZ is offered in 120/208 V, 120/240 V, 127/220 V, 139/240 V, 220/380 V, 277/480 V, 3-phase.
What size battery does the Kohler 50ROZ need?
The Kohler 50ROZ uses 1 battery, 12 V each, 640 CCA, per the manufacturer specification sheet.
What oil filter fits the Kohler 50ROZ?
The Kohler 50ROZ uses oil filter part number 229678.
What fuel filter fits the Kohler 50ROZ?
The Kohler 50ROZ uses fuel filter part number 223414.
Repair guides
4Step-by-step procedures compiled from the Kohler service manual for this model.
Parts
8| Part # | Description | Qty | System | |
|---|---|---|---|---|
| FP-4039A | Gasket Kit, Aftercooler | Gasket | Amazon eBay | |
| FP-RE38857-WS | Gasket Set, Complete Overhaul w/Front and Rear Seals | Gasket | Amazon eBay | |
| PG219S | Gasket Set, In-frame Overhaul | Gasket | Amazon eBay | |
| PG301PS | Gasket Set, Oil Pan | Gasket | Amazon eBay | |
| RG4906 | Fuel injection pump model and serial information on serial number plate | Fuel pump | Amazon eBay | |
| RG4622 | PTO serial number and model number on cover plate of PTO housing | Service part / kit | Amazon eBay | |
| RG4904 | Engine serial number plate | Service part / kit | Amazon eBay | |
| RG7225 | Saran serial number plate | 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 |
|---|---|---|---|
| Prime | 25% | 4.5 | 1.2 |
| Prime | 50% | 7.2 | 1.9 |
| Prime | 75% | 9.8 | 2.6 |
| Prime | 100% | 11.7 | 3.1 |
| Standby | 25% | 6.1 | 1.6 |
| Standby | 50% | 8.7 | 2.3 |
| Standby | 75% | 12.1 | 3.2 |
| Standby | 100% | 16.3 | 4.3 |
Available documents
This page was generated from the 7 manufacturer documents above by automated extraction; every figure shown is copied from one of them. How the data is compiled.