Hitachi EX1200-7B Backhoe Hydraulic Excavator Workshop Manual WKAB90-EN-00 – PDF Download

Description

Hitachi EX1200-7B Backhoe Excavator Workshop Manual – WKAB90-EN-00

This is the complete Hitachi EX1200-7B Hydraulic Excavator Workshop Manual, published under document number WKAB90-EN-00 by Hitachi Construction Machinery Co., Ltd. Written for the experienced technician, it delivers the maintenance and repair information needed to remove, install, disassemble, assemble, inspect, and adjust the machine’s major systems and components. It is the backhoe front specification volume, and it sits alongside the Technical Manual (Operational Principle, TOKAB90-EN) and the Technical Manual (Troubleshooting, TTKA90-EN) in Hitachi’s three-part service documentation set.

Where the Technical Manuals explain how the machine operates and how to diagnose faults, this Hitachi EX1200-7B Backhoe Excavator Workshop Manual focuses on the physical work: lifting and holding heavy assemblies, matching marks before disassembly, correct bolt tightening order, recommended replacement of seals and rings, and the special tools required to complete each job safely. If you are pulling a swing device, overhauling a travel motor, resealing a boom cylinder, or replacing the hydraulic oil tank, this is the reference that gives you the sequence, the wrench sizes, the torque values, and the handling precautions for every step.

File Details

• Manual type: Workshop Manual (Removal and Installation, Disassembly and Assembly)
• Brand: Hitachi Construction Machinery
• Model: EX1200-7B Hydraulic Excavator (Backhoe Front Specifications)
• Document number: WKAB90-EN-00
• Language: English
• File format: PDF
• Units: SI (International System of Units) with conversion table
• Related volumes: Technical Manual (Operational Principle) TOKAB90-EN, Technical Manual (Troubleshooting) TTKA90-EN

Chapters Covered

The manual is organised into five sections, each with grouped subsections:

• Section 1 – General: Precautions for Disassembling and Assembling; Tightening (bolts, nuts, piping joints, union joints, quick couplings, screw-in connections, split flanges, nut and bolt locking); Painting; Bleeding Air (hydraulic oil tank, hydraulic system, fuel system); Releasing Pressure; Preparation before Inspection and Maintenance
• Section 2 – Maintenance Standard: Uppertructure (pump device, swing motor); Undercarriage (travel device, center joint, front idler, upper and lower rollers, track); Front Attachment (pin and bushing, point, cylinder)
• Section 3 – Upperstructure: Cab; Counterweight; Engine (air cleaner); Radiator Assembly (radiator, intercooler, pump transmission oil cooler); Oil Cooler Assembly (oil cooler, fuel cooler); Hydraulic Oil Tank; Fuel Tank; Pump Device (pump transmission, main pump, main pump regulator, fan pump, fan pump regulator, pilot pump, transmission lubrication pump, pump control solenoid valve); Control Valve (swing control valve, housing, 4-spool and 5-spool control valve sides); Swing Device (swing motor, swing parking brake valve); Pilot Valve (left, right, travel); Solenoid Valve (pilot shut-off, 4-spool unit, 2-spool unit); Signal Control Valve; Urea SCR System (urea SCR muffler unit, DEF tank); Fan Valve (oil cooler fan valve, radiator fan valve); Fan Motor (oil cooler fan motor, radiator fan motor)
• Section 4 – Undercarriage: Swing Bearing; Travel Device (travel motor, brake valve); Center Joint; Track Adjuster; Front Idler; Upper and Lower Rollers
• Section 5 – Front Attachment: Front Attachment (boom, arm, bucket); Cylinder (boom cylinder, arm cylinder, bucket cylinder); Bushing and Point

Between them, these five sections turn the manual into a full teardown and rebuild guide for the EX1200-7B. The General section alone is worth the download, because it establishes the standard practices the rest of the book depends on: how to clean and inspect before starting, how to cap and tag open hose ends, when to replace O-rings and floating seals, how to read the matching marks, and how to tighten multi-bolt flanges and covers in the correct sequence. The Maintenance Standard section then supplies the numbers you measure against, with standard and allowable-limit values for plunger-to-cylinder-block clearances, spring free lengths, shoe thicknesses, bushing and roller wear, track pitch extension, and pin and bushing diameters across the front attachment. The Uppertructure, Undercarriage, and Front Attachment sections carry the actual removal, disassembly, assembly, and installation procedures for each component, from a 740 kg cab assembly down to the orifices and plugs inside a pump regulator.

Component Weights, Tools, and Handling Data

One of the practical strengths of this EX1200-7B Hydraulic Excavator Workshop Manual is that it treats the machine as a real object to be moved, not just a set of parts. Component weights are printed wherever they matter: the counterweight is called out at 18,300 kg, the hydraulic oil tank at 810 kg, the fuel tank at 710 kg, the radiator at 690 kg, the swing device at 690 kg, a main pump at 165 kg, and the urea SCR muffler at 186 kg. Lifting-bracket locations, eyebolt sizes and thread pitches (M12, M16, M20, M22, M27 and others), and nylon sling routing are given for each lift, so you can plan the crane or forklift before the machine comes apart. The manual also lists the wrench sizes and tightening torques for essentially every fastener it touches, from socket bolts inside a pilot valve to the 4000 N-m counterweight bolts, plus installation torque for couplings, flanges, clamps, and pipe joints.

What This Manual Helps You Do

• Remove and reinstall the cab, counterweight, engine-related covers, radiator, intercooler, oil cooler, fuel cooler, hydraulic oil tank, and fuel tank
• Pull, disassemble, inspect, and reassemble the pump device, main pump, fan pump, pilot pump, regulators, and pump control solenoid valves
• Service the control valve, including the housing, 4-spool and 5-spool sides, spools, relief valves, load check valves, anti-drift valves, and flow control valves
• Overhaul the swing device, swing motor, and swing parking brake valve
• Disassemble and rebuild the left, right, and travel pilot valves down to spools, springs, pushers, sleeves, and oil seals
• Remove and install the pilot shut-off solenoid valve and the 4-spool and 2-spool solenoid valve units
• Remove and service the signal control valve and urea SCR system, including the DEF tank and DEF sensor unit
• Service the oil cooler and radiator fan valves and fan motors
• Work the undercarriage: swing bearing, travel device, travel motor, brake valve, center joint, track adjuster, front idler, and upper and lower rollers
• Remove and install the boom, arm, and bucket, and overhaul the boom, arm, and bucket cylinders
• Replace bushings and dust seals throughout the front attachment
• Bleed air from the hydraulic oil tank, hydraulic system, and fuel system, and release residual pressure before opening a circuit
• Measure wear against Hitachi’s standard and allowable-limit values before deciding to reuse, repair, or replace a part

Why the Correct Procedures and Specifications Matter on an EX1200-7B

A 120-tonne-class excavator punishes guesswork. Under-tightened counterweight bolts, a floating seal installed with a twisted O-ring, a spool fitted the wrong way round, or a pump assembled with the valve plate facing the wrong direction will not simply cause a nuisance leak – they can lead to a sudden failure on a machine that is moving serious loads. This Hitachi EX1200-7B Workshop Manual spells out the details that prevent those failures: matching marks before disassembly, the correct direction for U-rings, backup rings, and valve plates, the order in which multi-bolt covers and flanges must be tightened, the parts that must be replaced rather than reused, and the thread-locking and sealing compounds specified for each joint. It also tells you when to stop and measure instead of assume, giving standard and allowable-limit figures for the clearances and wear surfaces that determine whether a component goes back into service or onto the scrap pile.

Instant PDF Delivery

This Hitachi EX1200-7B Backhoe Excavator Workshop Manual is delivered as an instant PDF download, so there is no shipping and no waiting for a disc or a printed binder. The file opens on any device – laptop, tablet, or phone – and can be printed page by page, so you can take just the section you need into the workshop, mark it up, and keep the master file clean. Whether you are a Hitachi dealer technician, an independent heavy-equipment mechanic, or an owner-operator responsible for a fleet, having WKAB90-EN-00 on hand means you can plan the job, order the right seals and fasteners up front, and work to the same procedures Hitachi’s own service personnel use. Download it once and it stays with you for the life of the machine.