Part of the Kubota Repair Manuals.
This downloadable PDF is the factory Kubota workshop manual for the RT and RT DI series diesel engines, 113 pages of specifications, service procedures, and troubleshooting. It covers the RT80 through RT140 direct and indirect injection engines used across Kubota equipment.
The manual documents tightening torques, full engine specifications for both RT and RT DI, performance graphs, dimensions, and step by step procedures for removing the engine, measuring wear on the cylinder head, valves, liners, and pistons, then reassembling to spec. A maintenance schedule and a troubleshooting chart round it out.
Mechanics rebuilding or overhauling one of these engines can work straight from the printed pages, checking every clearance and torque against the factory figures. View it on any device or print the sections you need for bench work.
What's Inside This Manual
| System | Pages | Key Topics |
|---|---|---|
| Tightening Torque Table | 4 | Tightening Torques Table, Strength of Bolt Indication, Indication Material Table |
| Tightening Torques Diesel Engine Rt | 5 | Tightening Torques Diesel Engine, Rt Table, Engine Component Torque Values, Comparision |
| Tightening Torques Diesel Engine Rt Di | 6 | Tightening Torques Diesel Engine Rt Di Table, Engine Component Torque Values, Comparision |
| Rt Engine Specifications | 7-10 | Cylinder Head Specifications, Valve Specifications, Valve Spring Specifications, Rocker Arm Specifications, Camshaft Specifications, Liner Specifications |
| Rt Di Engine Specifications | 11-14 | Cylinder Head Specifications, Valve Specifications, Valve Spring Specifications, Rocker Arm Specifications, Camshaft Specifications, Liner Specifications |
| Rt Engine Radiator Net Specification | 15-16 | Engine Type and Cylinders, Bore and Stroke, Total Displacement, Max Power, Net Power, Max Torque, Fuel Consumption, Compression Ratio |
| Rt Engine Performance Graph | 17-18 | RT80 Performance Graph, RT90 Performance Graph, RT100 Performance Graph, RT110 Performance Graph, RT120 Performance Graph |
| Rt Di Engine Performance Graph | 19-20 | Rt 100 Di Performance Graph, Rt 110 Di Performance Graph, Rt 120 Di Performance Graph, Rt 140 Di Performance Graph |
| Dimensions | 21 | Engine Dimensions Diagram, Model Dimensions Table, Model Specifications |
| Features | 22 | Engine Components Diagram |
| Removing Engine | 23-45 | Changing Coolant (Water Drain), Draining Engine Oil (Oil Drain), Draining Fuel (Fuel Drain), Removing Fuel Tank Side Cover 1 and 2, Removing Fuel Tank Cover 3, Removing Engine Hook |
| Measurement | 46-77 | Checking Compression Pressure, Checking Cylinder Head Surface Flatness (Distortion of Cylinder Head Surface), Checking Valve Seat Width, Checking Valve Recessing |
| Reassembling | 78-98 | Reassembling Liner, Reassembling Tappets, Reassembling Crankshaft, Reassembling Piston to Connecting Rod, Reassembling Piston Ring, Arranging Piston Ring Gap |
| After Reassembling | 99-107 | Filling Coolant, Filling Engine Oil, Filling Fuel, Closing Fuel Cock, Removing Injection Pipe and Fuel Line From Fuel Filter, Removing Fuel Pump, Removing Spring Lock and Cup Pin |
| Maintenance | 108 | Maintenance Schedule Table, Coolant Maintenance, Engine Oil Maintenance, Air Cleaner Maintenance, Solar Oil Filter Maintenance, Fan Belt Maintenance, Solar Oil Tank Maintenance |
| Troubleshooting | 109-113 | Engine Does Not Start, Engine Shakes Abnormal, Engine Power Down, Exhaust Gas Color Is Abnormal, Engine Oil Consumption Is Higher Than Normal, Engine Oil Is Clearer Than Normal |
Quick Reference Specifications
| Specification | Value | Page |
|---|---|---|
| All Models | ||
| General Bolt Torque (M6, Standard) | 80 - 95 kg.-cm. | p. 4 |
| General Bolt Torque (M10, Standard) | 400 - 460 kg.-cm. | p. 4 |
| Flywheel mounting nut torque | 3500 ± 500 kg.-cm. | p. 5 |
| Valve stem clearance (Allowable limit) | 0.1 mm. | p. 7 |
| Piston ring gap (Allowable limit) | 1.2 mm. | p. 8 |
| Oil pressure (Standard) | 2.5 kg/cm2 | p. 9 |
| Fan belt tension | 10 - 15 mm. | p. 10 |
| Radiator cap pressure (Standard) | 0.85 - 1.05 kg/cm2 | p. 10 |
| RT | ||
| Cylinder head mounting nut torque, RT | 1100 ± 100 kg.-cm. | p. 5 |
| RT DI | ||
| Cylinder head mounting nut torque, RT DI | 1500 ± 100 kg.-cm. | p. 6 |
| RT80-RT90 | ||
| Coolant capacity, RT80-RT90 | 1.6 L. | p. 15 |
| RT120-RT140 | ||
| Coolant capacity, RT120-RT140 | 2.2 L. | p. 16 |
