This is the Cat SIS service bundle for the 311 and 312 excavators, serial prefix 6GK, with the 3064 and 3066 engines. It is not one authored book - Cat stitched the individual service publications together, so you get systems operation, testing and adjusting, and disassembly/assembly side by side. The heart of it is the hydraulic testing material: main and line relief settings, swing crossover, power shift pressure, pump flow and calibration - the numbers that tell you whether a tired machine needs a pump or just a screwdriver on a relief valve. Engine, fuel, cooling, electrical schematics for the 311/312, undercarriage, travel and swing drives, cab and linkage service are all in here. This is a gauges and stopwatch machine, and the book is written that way.
Other edition of this manual
What's Inside This Caterpillar 312 Repair Manual
| System | Pages | Key Topics |
|---|
| Air Inlet and Exhaust System | 2-52 | Turbocharger, Exhaust and Air Intake Service |
| Basic Engine | 53-390 | Cylinder Head, Block, Pistons, Crankshaft and Engine Service |
| Cooling System | 391-474 | Radiator, Water Pump, Thermostat and Cooling Service |
| Electrical and Starting System | 475-1648 | Starting and Charging, System Schematics and Testing, Plus Cat's Bundled Add-On Publications (EquipmentManager, Product Link, R134a Air Conditioning) |
| Engine Arrangement | 1649-1691 | Engine Arrangement Systems Operation and General Information, Testing and Adjusting, Troubleshooting, Engine Speed Check, And Engine-To-Main-Hydraulic-Pump Separation |
| Frame and Body | 1692-1708 | Frame, Covers and Body Panels |
| Fuel System | 1709-1979 | Injection Pump, Injectors and Fuel System Service |
| Hydraulic System | 1980-2808 | Systems Operation, Testing and Adjusting (Main and Line Relief Valve Settings, Swing Crossover, Power Shift Pressure, Pump Flow and Calibration), Pumps, Valves and Cylinders |
| Implements | 2809-2881 | Boom, Stick and Bucket Linkage Service |
| Lubrication System | 2882-2949 | Oil Pump, Filters and Lubrication Service |
| Machine Arrangement | 2950-2962 | Machine Arrangement Systems Operation, Service Intervals, Testing and Adjusting, And Heating and Air Conditioning Service References |
| Operator Station | 2963-3529 | Cab, Seat, Controls and Monitor |
| Power Train | 3530-3592 | Travel Motors, Final Drives and Swing Drive |
| Service Equipment and Supplies | 3593-3647 | Dealer Service Tools and Shop Supplies |
| Undercarriage | 3648-3702 | Track, Rollers, Idlers and Recoil Spring Service |
| Work Tools | 3703-3711 | Work-Tool Mounting and Coupler Service |
| Torque Specifications | 3712-3760 | Cat's Generic Torque Charts (Metric ISO, English SAE, Fittings, Plugs, Hose Clamps) |
| Schematic | 3761-3849 | Named Schematic Sheets - the 311 and 312 Excavators Electrical System (2003) - Plus the Fluid Power and Electrical Graphic Symbol Legends |
Quick Reference Specifications
| Specification | Value | Page |
|---|
| 312 |
| Main relief valve pressure (standard setting) | 27500 +/- 490 kPa (4000 +/- 72 psi) | p. 2214 |
| Main relief valve pressure (high-pressure / travel) | 34300 +/- 490 kPa (5000 +/- 72 psi) | p. 2328 |
| Swing crossover relief valve pressure | 23000 +/- 980 kPa (3350 +/- 140 psi) | p. 2215 |
| Line relief valve pressure (boom / bucket) | 26000 +/- 1470 kPa (3750 +/- 215 psi) | p. 2216 |
| Line relief valve pressure (higher circuit) | 31400 +/- 1470 kPa (4550 +/- 215 psi) | p. 2217 |
| Line relief valve pressure (highest circuit) | 36300 +/- 1470 kPa (5250 +/- 215 psi) | p. 2218 |
| Power shift pressure (test constant) | 1780 +/- 50 kPa (260 +/- 7 psi) | p. 2229 |
| 311 and 312 |
| Proportional reducing valve | 0.16 to 0.63 A, pressure range 0 to 3150 kPa (0 to 455 psi) | p. 2171 |
| Engine speed by dial setting | 700 rpm (low idle, dial 1) up through 1100 / 1210 / 1320 / 1430 / 1540 / 1650 / 1760 rpm | p. 2176 |
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![Caterpillar 312 repair manual - Electrical and Starting System, [Elec #32] Engine Stalls](https://youfixthis.com/wp-content/uploads/2019/12/caterpillar-312-6gk-repair-manual-excavator-217db-page-1284-150x212.webp "caterpillar-312-6gk-repair-manual-excavator-217db-page-1284")
