The Kubota D902 is one of the most capable compact diesel engines in its class. Whether you’re verifying specifications, planning a rebuild, or ordering replacement parts, this guide provides a complete technical reference to help you get the most from your D902.
Kubota D902 Engine Variants & Common Model Codes
Many owners and mechanics struggle to identify which version of the D902 they own. Matching the correct model ensures accurate parts selection and emission compliance.
Kubota D902 Engine Variants
| Model Code | Emission Tier / Certification | Key Differences | Typical Equipment |
|---|---|---|---|
| D902‑E2B | Tier 2 / Stage II | Early version with a mechanical governor | Pre‑2010 compact tractors, generators |
| D902‑E3B | Tier 3 / Stage IIIA | Improved fuel system and combustion design | Mini skid‑steers, turf equipment |
| D902‑E4B | EPA Tier 4 Final / Stage V | Lower emissions and refined E‑TVCS optimization | Modern mini‑excavators, compact utility vehicles |
Note: Check your engine’s serial number plate (usually on the crankcase or valve cover) to confirm the exact model and ensure parts compatibility.
Operating & Performance Features
These real‑world performance specs help owners gauge power output, torque range, and fuel economy for their specific application.
Performance Highlights
- Peak Torque: ~56 Nm (41 lb‑ft) @ 2600 rpm
- Fuel Consumption: Approx. 0.28 – 0.31 L/hp·hr (~1.9 gal/hr at full load)
- Continuous Rating: ~21 hp @ 3200 rpm for 100 % load operation
These metrics provide practical insight for fuel budgeting, load management, and performance benchmarking.
D902 Serial Number Identification Guide
Your serial number is the key to decoding production details and obtaining the right service parts.
How to Locate & Identify Your D902 Serial Number:
- The number is engraved on the engine crankcase, typically on the right-hand side near the injection pump.
- Format Example: D902‑xxxxx
- The prefix (D902) indicates the engine family; the numeric suffix identifies the production sequence and emission variant.
Always reference this full serial number when ordering parts or service components. Learn more with our Kubota Tractor Serial Number Lookup Guide.
Lubrication & Maintenance Quick Lookup
Regular maintenance keeps your D902 performing efficiently and prolongs engine life. The chart below summarizes key service intervals and fluid capacities.
| Component | Capacity / Specification | Recommended Service Interval |
|---|---|---|
| Engine Oil | Approx. 2.8 – 3.1 L (depending on oil pan; verify with dipstick). Use API CJ‑4 / CK‑4 10W‑30 or 15W‑40 diesel oil. | Every 100 hrs (standard) / 200 hrs (with synthetic) |
| Coolant | Approx. 3.0 L (50/50 ethylene glycol premix) | Every 1,000 hrs or 2 years |
| Fuel Filter | — | Every 200 hrs or sooner if fuel quality is poor |
| Air Filter | — | Inspect every 50 hrs; replace if restricted |
| Valve Clearance | Intake & Exhaust: 0.145 – 0.185 mm (cold) | Every 800 hrs |
Cold‑Weather Operation Tips
The D902 is a favorite for snow and cold‑region equipment. Proper preparation ensures reliable starts and minimal wear.
Cold‑Start & Winter Operation Tips
- Use a block heater or intake heater when the ambient temperature is below –5 °C (23 °F).
- Switch to winter‑grade diesel (No. 1‑D) to prevent fuel gelling.
- Check that your battery meets OEM CCA rating—≥ 450 CCA is recommended for 12 V systems in freezing climates. (Learn how to choose the right battery for your equipment.)
- Allow at least 30 seconds of warm‑up at fast idle before applying load.
Troubleshooting Chart
Use this simplified chart for rapid fault detection before teardown.
| Symptom | Likely Cause | Recommended Action |
|---|---|---|
| Hard to start cold | Faulty glow plugs, weak battery, incorrect oil grade | Check glow‑plug resistance; use 10W‑30 oil in cold weather |
| Low power | Clogged air filter, worn injectors, restricted fuel flow | Inspect filters; test injector spray pattern |
| Overheating | Low coolant, blocked radiator, worn water‑pump impeller | Clean radiator; replace water pump if needed |
| Excessive smoke | Incorrect fuel timing, clogged injector, piston wear | Adjust timing; check compression |
| Oil leak at the front seal | Worn crank seal or crankcase pressure buildup | Replace seal; inspect breather system |
Cross‑References to Similar Kubota Engines
These comparable engines share architecture with the D902, aiding retrofitters or rebuilders in identifying substitutes.
| Model | Displacement (L) | Output (HP) | Notes |
|---|---|---|---|
| D722 | 0.719 | ~18 hp | Smaller sibling of the D902. (Explore the Kubota D722 engine specs.) |
| D905 | 0.898 | ~25 hp | Member of the Super 05 series with a similar layout |
| D1005 | 1.001 | ~27 hp | Slightly larger displacement; same design family. (View the Kubota D1105 engine specs guide.) |
Environmental Compliance & Future Updates
The Kubota D902‑E4B / Stage V model meets the latest EPA Tier 4 Final and EU Stage V standards. Through refined E‑TVCS combustion, it achieves ultra‑low emissions without requiring a diesel particulate filter (DPF), offering simplified maintenance and continued global compliance.
Recommended Tools & Torque Specs
Critical Note: Torque values below are for general reference only. Always verify with the official Kubota Service Manual for your specific serial number before assembly. Incorrect torque can cause severe engine damage.
| Component | Torque | Notes |
|---|---|---|
| Cylinder Head Bolts | 49 – 54 Nm (36 – 40 lb-ft) | Tighten in 3 stages , working from the center outward |
| Connecting Rod Bolts | 29.4 – 33.3 Nm (21.7 – 24.6 lb-ft) | Use new nuts if removed |
| Main Bearing Cap Bolts | 29.4 – 33.3 Nm (21.7 – 24.6 lb-ft) | Lubricate threads with clean engine oil |
| Injector Hold‑Down Bolts | 18 Nm (13 lb‑ft) | Do not overtighten |
| Glow Plug | 10 Nm (7.4 lb‑ft) | Hand‑tight + ¼ turn |
Where to Find Genuine Parts & Support
To maintain performance and longevity, always use OEM or equivalent‑grade parts. For general upkeep, check out our 10 Maintenance Tips for Kubota Tractors.
Final Words
Every Kubota D902 part we supply meets or exceeds OEM standards, helping you extend the life of your equipment without costly downtime. Get your Kubota D902 back to its top condition.
Explore the full range of Kubota engine parts at FridayParts.com right now!
