Komatsu JTHB-3 Series Hydraulic Breakers Shop Manual SEN06343-00

Description

Komatsu JTHB-3 Series Hydraulic Breakers Shop Manual SEN06343-00

The Komatsu JTHB-3 Series Hydraulic Breakers Shop Manual SEN06343-00 is a detailed service and repair reference for the JTHB hydraulic breaker range. It covers models from the compact JTHB08-3 through the larger JTHB450-3, including S-series variants listed in the manual. The document concentrates on the hydraulic breaker itself; for excavator-specific service information it directs the technician to the applicable excavator shop manual.

This manual combines model specifications with hydraulic operating theory, installation checks, P-Q pressure/flow measurement, fault diagnosis, overhaul procedures, component inspection, wear limits, tightening data and reassembly instructions. The large illustrated disassembly and assembly section is especially useful when servicing pistons, cylinders, control valves, bushings, seals, side bolts, hose adapters and nitrogen-charged cushion chambers.

File Details

• Manual type: Shop Manual
• Brand: Komatsu
• Models: JTHB08-3, JTHB10-3, JTHB20-3, JTHB20S-3, JTHB30-3, JTHB30S-3, JTHB40-3, JTHB40S-3, JTHB50-3, JTHB60-3, JTHB60S-3, JTHB120-3, JTHB120S-3, JTHB160-3, JTHB210-3, JTHB210S-3, JTHB350-3, JTHB450-3
• Serial numbers: 10001~
• Language: English
• Pages: 112
• File format: PDF
• Document number: SEN06343-00
• Issue date: 3 April 2013

Breaker Specifications and Model Coverage

The opening specification section gives model-by-model dimensions and operating data for the JTHB range. Tables cover overall breaker dimensions, bracket configurations, working weights, oil flow, operating pressure, impact rate, chisel diameter, chisel weight, hose size, nitrogen gas pressure, suitable base-machine tonnage and Komatsu excavator examples. This makes the manual useful both before installation and during service work when breaker settings must be checked against the correct model data.

The dimensional drawings identify length including the chisel, width, height and bracket-only length. Specification tables then distinguish the different bracket arrangements used through the range, including side mount, two-piece top mount, top box and silenced configurations where applicable.

Hydraulic Breaker Construction and Operating Principle

Illustrated sectional drawings identify the major internal and external components of the breaker, including the side bolts, cylinder cover, gas valve, piston, packing bushing, control valve, control valve box, hose adapters, chisel holder, chisel bushings, retainer pins, seals and grease points. Separate illustrations are provided for smaller and larger JTHB configurations.

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The manual explains the operating cycle in four stages: upward piston movement, reversing, downward movement and impact. Hydraulic flow through the numbered chambers and the control-valve movement is described so technicians can understand how repeated piston cycles produce continuous blows. That system explanation is particularly useful when diagnosing weak impact, erratic operation or failure to cycle.

Chapters Covered

• 00 Index and foreword
  • Foreword, safety and general information
  • Important safety notice
  • General servicing precautions
  • Precautions for slinging work and making signals
  • Mobile and overhead crane precautions
  • Selecting wire ropes
  • Handling of hydraulic equipment
  • Flushing and hydraulic cleaning practices
• 01 Summary
  • Dimensions
  • Specifications
  • Working weights and bracket types
  • Oil flow and operating pressure
  • Impact rates, chisel sizes and gas pressure
  • Base-machine and excavator application data
• 10 Structures, Operation and Maintenance
  • Structures of the hydraulic breaker
  • JTHB08-3 through JTHB50-3 construction
  • JTHB60-3 through JTHB450-3 construction
  • Principle function
  • Upward movement, reversing, downward movement and impact cycle
• 30 Testing and Adjustment
  • Hydraulic and electric circuit diagrams
  • Delivery inspection and adjustment
  • Komatsu PC200 piping example
  • Old-model and other-company piping reference
  • Breaker mounting checks
  • P-Q pressure and flow measurement
  • Purpose and interpretation of P-Q measurement
  • Hydraulic breaker relief-valve setting
  • Throttle-position setting
  • Air bleeding and test run
  • P-Q check sheet
• 40 Troubleshooting
  • Hydraulic breaker troubleshooting check sheet
  • Breaker-related hydraulic faults
  • Parts-related failures
  • Excavator and piping-related problems
  • Low P-Q and restriction diagnosis
  • Seizure, gas-pressure and oil-leakage diagnosis
  • Chisel and retainer-pin problems
  • Hydraulic oil temperature problems
• 50 Disassembly / Assembly
  • Hydraulic breaker disassembly and assembly tools
  • Cleaning the breaker and bracket
  • Side mount, two-piece top mount and top box bracket disassembly
  • Bracket assembly/disassembly charts
  • Hydraulic breaker work-table setup
  • Cylinder cover and side bolt nut removal
  • Piston removal
  • Control valve and control valve box removal
  • Cylinder and side bolt removal
  • Hose adapter removal
  • Seal removal
  • Hydraulic breaker assembly/disassembly charts
  • JTHB plug torque chart
  • Seal inspection
  • Chisel bushing inspection and replacement
  • Chisel holder bushing inspection and replacement
  • Control valve and control valve box inspection and repair
  • Piston inspection and repair limits
  • Cylinder inspection and Flex-Hone guidance
  • Retainer pin inspection
  • Chisel holder and chisel bushing installation
  • Helisert installation and thread sizes
  • Cylinder seal installation
  • Piston and packing bushing assembly
  • Control valve and control valve box assembly
  • Filling the breaker with hydraulic oil
  • Cylinder cover and side bolt nut tightening
  • Power wrench procedure
  • Alternative side bolt nut tightening method
  • Hose adapter assembly
  • Nitrogen cushion chamber check and recharge
  • Broken side bolt replacement

Taken together, these chapters provide the information needed to inspect breaker condition, verify hydraulic supply, isolate performance faults, dismantle the unit safely, measure wear, repair or replace serviceable components and rebuild the breaker using the specified tightening and charging procedures.

Testing, Adjustment and Troubleshooting

The testing section goes beyond basic service instructions by showing how breaker performance is matched to the excavator hydraulic system. It explains P-Q measurement, relief-pressure checks, flow settings, throttle-position adjustment and test-run preparation. A JTHB210-3 example shows how pressure and flow results can reveal low relief settings, insufficient flow or excessive flow before the breaker is placed into service.

The troubleshooting chapter links symptoms to likely causes and corrective actions. Covered problems include a breaker that will not impact, stops after operating for a period, produces erratic blows, lacks BPM, has weak impact energy or leaks oil. It also addresses chisel breakage, excessive bushing wear, excessive hydraulic oil temperature, piping restrictions, reduced pump performance, incorrect gas pressure, contamination, seizure and improper relief or throttle settings.

Overhaul, Inspection and Reassembly Information

The largest part of this Komatsu JTHB hydraulic breaker shop manual is devoted to workshop overhaul. Illustrated steps show bracket removal, breaker positioning, releasing cushion-chamber gas, removing the cylinder cover, piston, control valve, cylinder, side bolts, hose adapters and seals. Inspection procedures provide wear limits for bushings and pistons, guidance for checking seals and retainer pins, and repair directions for light seizure marks on valves, pistons and cylinder bores.

Model-specific assembly/disassembly charts provide bolt sizes, wrench sizes and tightening torques. Additional tables cover choke-plug torque, Helisert thread sizes, removal-jig dimensions, packing-bushing assembly-jig dimensions and recommended hydraulic-oil quantities for assembly. Reassembly instructions cover seal direction, component lubrication, anti-seize application, control-valve installation, cylinder cover tightening and nitrogen recharge. The cushion-chamber section specifies nitrogen pressures at different ambient temperatures and warns that no gas other than nitrogen should be used.

Repair With the Correct Procedures and Specifications

The Komatsu JTHB-3 Series Hydraulic Breakers Shop Manual SEN06343-00 supports practical workshop jobs ranging from hydraulic performance checks and breaker setup to troubleshooting, complete disassembly, component inspection, bushing and seal replacement, reassembly, torque setting and nitrogen charging. Having the correct model-specific measurements, wear limits, pressures and tightening data helps technicians avoid guesswork when repairing or rebuilding these breakers.

After purchase, the manual is supplied as an instant PDF download with no physical shipping. It can be opened on a compatible computer, tablet or phone and printed when a paper workshop reference is preferred.