All 474 pages of this McCormick GX Service Manual (OEM #SM 8-30140 GB) are written for one tractor family: your GX 40H. Inside: wiring diagrams for every circuit from starting and recharging to operator safety and hydrostatic plant, plus hydraulic schematics covering the rear power lift and auxiliary control valves. You get a full troubleshooting section for engine and gearbox faults, standard driving torque tables for metric fasteners, and step-by-step overhaul procedures for the PTO hydraulic clutch, hydrostatic transmission housing, and bevel gear pair adjustment. Set injector pressure to 216–226 bar on the GX 40H, or 196–206 bar on the 45H/50H; torque the high-pressure fuel pipe sleeve nut to 29.4–34.3 Nm. Stop chasing electrical faults with a bad wiring diagram. Bookmarked and searchable, so you can jump to any system by keyword and get back under the hood.
What's Inside This Manual
| System | Pages | Key Topics |
|---|---|---|
| General Information | 5-30 | Safety Notes, Danger Signs, Standard Driving Torque Values |
| Engine | 31-152 | General Features, Main Specifications, Lubrication, Cooling and Fuelling Circuit Diagrams, Engine Troubleshooting, Engine Splitting and Remounting, Compression Test |
| Engine/Transmission Coupling | 153-168 | Engine Coupling, Splitting-Remounting |
| Hydrostatic Gearbox | 169-216 | Sections, Troubleshooting for the Gearbox, Hydrostatic Transmission Housing - Splitting - Remounting, Hydrostatic Transmission Housing - Overhaul, PTO Hydraulic Clutch - Overhaul |
| Transmission | 217-278 | Driving Torque Values, Right or Left Side Final Drive Housing - Assembly Splitting Remounting, Driving Wheel Shaft - Overhaul, Bevel Gear Pair Adjustment |
| Power Take-Offs | 279-290 | Power Take-Off. Overhaul |
| Hydraulic Circuits | 291-336 | Sections and Perspective Views, Description of the Operating Mode of the Hydraulic Power Lift, Description of the Operating Mode of the Hydraulic Power Lift’s Valve System |
| Steering | 337-344 | Steering Cylinder, Hydrostatic Steering Pump, Control Valves, Pressure Filter, Rotary Pump, Differential Locking and Unlocking |
| Brakes | 345-356 | Main Brakes, Parking Brake, Oil-Cooled Discs, Pressure Plates, Control Rod, Flexible Steel Cables |
| Electrical System - Components | 371-382 | Maintenance |
| Electrical System – Ignition System | 383-392 | Starter Motor, Key-Switch, Electromagnet, Control Pinion, Battery, Ignition Relay |
| Electrical System – Recharging System | 393-402 | Tests and Troubleshooting |
| Electrical System - Battery | 403-414 | Maintenance and Battery Inspection |
| Electrical System – Electrical Circuits | 415-474 | Electrical System Components (Continued), Starting and Recharging Diagram (Diagram a), Operator Safety and Hydrostatic Plant Diagram (Diagram B/1) |
Quick Reference Specifications
| Specification | Value | Page |
|---|---|---|
| GX 40H | ||
| Injectors pressure setting, GX 40H | 216 ÷ 226 bar | p. 38 |
| GX 45H/GX 50H | ||
| Injectors pressure setting, GX 45H/GX 50H | 196 ÷ 206 bar | p. 38 |
| All Models | ||
| Auxiliary control valves maximum flow rate | 28 ÷ 36 l/min | p. 335 |
| Auxiliary control valves calibration pressure | 185 ÷ 190 bar | p. 333 |
| Thermostatic valve opening temperature | 69.5 ÷ 72.5 °C | p. 46 |
| Thermostatic valve lift height | ≥ 8.0 mm (≥ 85 °C) | p. 46 |
| Steering system filter filtering degree | 40 µm | p. 339 |
| Hydrostatic transmission external auxiliary cartridge filter | 10 micron | p. 178 |
| Engine oil cleaning type (on pump intake) | gauze filter | p. 39 |
| Engine oil cleaning type (on engine delivery) | cartridge filter | p. 39 |
| Steering circuit control valve unit adjustment pressure | 18 to 20 bar | p. 343 |
| Auxiliary control valves pressure setting | 185 ÷ 190 bar (188 ÷ 193 kg/cm²) | p. 329 |
