Part of the JCB Repair Manuals.
Looking for the exact teardown and rebuild procedures for your excavator? This 485-page JCB 8085 Service Manual PDF (OEM #9803/9990-1) breaks down the complete hydraulics, electrics, and track assemblies for the JCB 8085. You get high-quality wiring diagrams to trace stubborn electrical faults, plus full hydraulic circuit schematics showing every valve and pump connection. Open the file to find detailed exploded views of the undercarriage, routine maintenance schedules, and step-by-step troubleshooting charts. Dial in your hydraulic performance by setting the Main Relief Valve pressure to exactly 300 bar, and torque the track motor mounting bolts to 267-312 Nm. Stop wasting shop hours hunting for the right specifications. Grab this bookmarked download, pull it up on your tablet right next to the machine, and get your equipment back in the dirt.
What's Inside This Manual
| System | Pages | Key Topics |
|---|---|---|
| General Information | 1-35 | Introduction, Machine Identification, Service Tools, Torque Settings, Service Consumables, Terms and Definitions |
| Care & Safety | 36-53 | Service Manual - JCB 8085, Section 1 - General Information, Section 2 - Care & Safety, Section 3 - Routine Maintenance, Section A - Attachments, Section B - Body & Framework, Section C - Electrics, Section E - Hydraulics |
| Routine Maintenance | 54-107 | Health and Safety, Service Schedules, Fluids, Lubricants and Capacities, Cleaning the Machine, Checking for Damage, Seat Belt, Checking the ROPS/FOPS Structure |
| Body & Framework | 108-149 | Technical Data, Air Conditioning (Basic Operation, Safety Procedures, Inspection, Fault Finding, Service Procedures), Cab (Direct Glazing) |
| Electrics | 150-319 | Technical Data (Fuses and Relays), Basic System Operation (Switches and Controls), Schematic Diagrams (Component Identification) |
| Hydraulics | 320-427 | Technical Data (Description and General Data), Service Procedures (Hydraulic Contamination, Cleaning Operation) |
| Transmission | 428-441 | Service Manual - JCB 8085, Section 1 - General Information, Section 2 - Care & Safety, Section 3 - Routine Maintenance, Section A - Attachments, Section B - Body & Framework, Section C - Electrics, Section E - Hydraulics |
| Tracks | 442-479 | Technical Data, Idler Wheel and Recoil Unit, Grease Cylinder, Drive Sprocket, Top Roller, Bottom Roller |
| Engine | 480-485 | Service Manual - JCB 8085, Section 1 - General Information, Section 2 - Care & Safety, Section 3 - Routine Maintenance, Section A - Attachments, Section B - Body & Framework, Section C - Electrics, Section E - Hydraulics |
Quick Reference Specifications
| Specification | Value | Page |
|---|---|---|
| Main Relief Valve (MRV) Pressure | 300 bar (4350 lbf/in2) | p. 349 |
| Servo Relief Pressure | 35 bar (508 lbf/in2) | p. 351 |
| Track motor mounting bolts torque | 267-312 Nm (196-229 lbf ft) | p. 438 |
| Engine oil filter replacement interval | Change at 500 hours | p. 61 |
| Engine oil filter installation torque | hand-tight, then turn another 90 degrees | p. 84 |
| Fuel filter element replacement interval | Change at 500 hours | p. 61 |
| Fuel pre-filter/sedimenter drain and clean interval | Drain and Clean at 50 hours | p. 61 |
| Fuel pre-filter/sedimenter-filter replacement interval | Change at 500 hours | p. 61 |
| Fan belt deflection | approximately 7 mm (0.28 in.) | p. 88 |
| Alternator mounting bolt torque | 20.4 - 27.2 Nm (15.0 - 20.0 lbf ft) | p. 154 |
