The John Deere 4.5 L is a 4.5 L engine. It powers generator sets from Kohler, including the 120REOZT4 and 90REOZT4.
Also known as: John Deere 4.5 L
Part of the John Deere 4.5 engine family — 2 variants share parts & fitment.
| Displacement | 4.5 L |
|---|
| Item | Action | Hours | Months | Notes |
|---|---|---|---|---|
| accessory/drive belt tension | Adjust | 125 hr | 12 mo | Schedule A, Schedule B, Schedule C |
| air filter element | Replace | 125 hr | 12 mo | Schedule A, Schedule B, Schedule C |
| battery condition/fluid level | Inspect | 125 hr | 12 mo | Schedule A (every year or 125 hours), Schedule B, Schedule C |
| lubricating oil and oil filter | Replace | 200 hr | 12 mo | First service — 25-hour engine break-in, then Schedule A/B/C (1 yr or 200 hrs, whichever first) |
| coolant system | Drain | 250 hr | 24 mo | Schedule B and Schedule C (every 2 years or 250 hours) |
| spark plugs | Clean | 250 hr | 24 mo | clean/gap/replace, Schedule B and Schedule C |
| critical fasteners | Other | 1000 hr | Schedule C only, tighten critical fasteners, every 1000 hours | |
| upper and lower radiator hoses, engine coolant bypass hoses, block heater hoses | Replace | 1000 hr | Schedule C, every 1000 hours |
Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.
| Type | Item | Value | Unit | Condition |
|---|---|---|---|---|
| Gap | Spark plug gap | 0.012-0.017 in (0.31-0.45 mm) | in/mm | |
| Other | Compression ratio | 9.9:1 (48 kW); 8.85:1 (60/80 kW) | ||
| Pressure | LP fuel pressure | 5-14 in water column (1.24-3.48 kPa) | in water column / kPa | |
| Pressure | NG fuel pressure | 3.5-14 in water column (0.87-3.48 kPa) | in water column / kPa | |
| Speed | Fan speed | 2,100 | rpm (2100 for 60/80kW) | |
| Speed | Rated synchronous rpm | 1,800 | rpm | |
| Temperature | Max ambient temp | 140 | °F (50°C) | |
| Temperature | Max operating air temp on radiator | 150 | °F (60°C) | |
| Temperature | Thermostat (full open) | 194°F (90°C) [48kW]; 160°F (71°C) [60/80kW] | °F/°C | |
| Torque | Spark plug torque | 28 | ft-lbs (38 Nm) | |
| Voltage | Steady state governor regulation | ±0.25 | % | |
| Voltage | Voltage regulation | ±1 | % |
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 |
|---|---|---|---|---|---|
| Coolant | Peak Fleet-Charge 50/50 ethylene glycol type coolant | 10.0 qt/L | Do not use propylene glycol type coolant; use demineralized or distilled water; anti-freeze dilution ratio 40-60% | ||
| Engine oil | 5W-20 (factory fill); 5W-30 semi-synthetic at first oil change; synthetic oil meeting/exceeding SAE specs after break-in; 5W-30 synthetic below 32°F (0°C) | API SJ or SH (detergent oil) | 12.0 qts (11.36 L) | Do not use special additives; once synthetic oil is used, use for life of generator | |
| Fuel | Natural Gas (NG) min 1,000 BTU/cu ft (37.26 MJ/cu m); Liquid Propane (LP) min 2,520 BTU/cu ft (93.8 MJ/cu m) | minimum LP tank size 250 gal (946 L) recommended if converting from NG |
Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.
⚠ High voltage present at transfer switch and terminals
Tools: AC voltmeter, frequency meter, clamp-on amp meter
⚠ Batteries emit explosive gases; always connect positive battery cable first to avoid spark
⚠ Allow engine to cool before draining oil
Tools: clean lint-free cloth
⚠ Do not disconnect spark plug wires with engine running
Tools: spark plug socket wrench, wire feeler gauge, wire brush
⚠ Allow engine to cool before draining coolant
⚠ Do not allow coolant to contact skin or eyes
Tools: two wrenches, funnel
⚠ Allow engine to cool before draining oil
⚠ Used motor oil has been shown to cause skin cancer in laboratory animals
Tools: two wrenches
Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.
Other equipment known to use this engine, via filter-application cross-reference — useful for sourcing parts even when your exact machine isn't listed elsewhere on this page.
The John Deere 4.5 L has a displacement of 4.5 liters.
The John Deere 4.5 L powers 2 generator set(s), including Kohler 120REOZT4, Kohler 90REOZT4.