Pages from 9803-4170 – JCB Wheeled Loading Shovel 412S, 414S, 416S Service Manual
Complete workshop & service manual with electrical wiring diagrams for JCB Wheeled Loading Shovel 412S, 414S, 416S. It’s the same service manual used by dealers that guaranteed to be fully functional and intact without any missing page.
This JCB Wheeled Loading Shovel 412S, 414S, 416S service & repair manual (including maintenance, overhaul, disassembling & assembling, adjustment, tune-up, operation, inspecting, diagnostic & troubleshooting…) is divided into different sections. Each section covers a specific component or system with detailed illustrations. A table of contents is placed at the beginning of each section. Pages are easily found by category, and each page is expandable for great detail. The printer-ready PDF documents work like a charm on all kinds of devices.
9803-4170 – JCB Wheeled Loading Shovel 412S, 414S, 416S Service Manual.pdf
EXCERPT:
Service Manual
Wheeled Loading Shovel – 412S, 414S, 416S
Section 1 – General Information
Section 2 – Care and Safety
Section 3 – Routine Maintenance
Section A – Attachments
Section B – Body and Framework
Section C – Electrics
Section E – Hydraulics
Section F – Transmission
Section G – Brakes
Section H – Hydraulic Steering
Section K – Engine
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Basic System and Operation
General Description
The main components of the 412S and 414S Wheeled Loader hydraulic systems are the pumps, loader valve block, priority valve, servo-valve, steering valve, brake valve, tank, rams and filters. For descriptions of the steering and brake valves, refer to the relevant sections.
The pumps (PI and P2) are installed as a single unit and driven by the engine to supply pressurised oil to the system. P1 supplies the system and the loader block spools to give the lift and bucket services. P2 supplies the loader block auxiliary (if installed) and Quickhitch service spools only. The output from P2 can be sent to the tank by the operation of the loader block unloading spool and this lets the engine power to be fully applied to P1.
A pressure regulated outlet from the priority valve is sent to the servo-valve, which sends it to the loader valve service spools as control inputs. When the servo-control valve is operated it causes the selected service valve spool in the loader valve block to send the pressurised oil from the pumps to the selected service ram. The pressurised oil forces the piston along the bore to give a service movement. As the piston moves, the oil is pushed from the opposite end of the ram and returns to the tank through a filter.
The relief valves in the system prevent undue pressure increases through internal and external sources.
When the valve blocks are assembled, tighten the tie-rods to 67 lbf ft (91 Nm).
The main components of the 416 Wheeled Loader hydraulic system are the pump, loader valve block, priority valve, servo valve, steering valve, tank, rams and filters.
For descriptions of the steering and brake valves, refer to the relevant Sections.
A separate gear pump supplies the brake circuit.
The variable flow piston pump is driven by the engine and delivers pressurised oil to the priority valve section of the loader valve block. The priority valve ensures that the steering circuit has first demand on pump flow and pressure. A pressure regulated outlet from the loader valve is routed to the servo valve which in turn is redirected to the loader valve service spools as control inputs.
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