1998 Takeuchi TB025 / TB030 / TB035 Mini Excavator Workshop Manual (P/N WE3-301E2)

This 1998 Takeuchi workshop manual covers the TB025, TB030, and TB035 compact excavators with steel or rubber crawlers. Document reference WE3-301E2, edition 07.98.

• Drive system: Engine removal and installation, radiator and oil-cooler removal, fuel-tank service, engine mounts, and pump-coupling construction.

• Undercarriage: Steel and rubber crawler removal and installation, carrier and track rollers, idlers, sprockets, and track-tension inspection.

• Hydraulic units: Pump disassembly and reassembly, control-valve and pilot-valve repair, cylinder seal replacement, inspection limits, and post-assembly testing.

• Travel and slew drives: Travel-motor and planetary-reduction service, parking-brake components, and separate slew-motor procedures for versions with and without parking brakes.

• Frame and attachments: Upper-frame and cabin removal, boom, arm, bucket, swing-bracket, and dozer-blade removal, plus bucket-clearance adjustment.

• Fault diagnosis: Hydraulic circuit diagrams, electrical wiring diagrams, symptom-based troubleshooting charts, and methods for checking machine performance.

Written for personnel engaged in machine maintenance, this manual calls for workshop lifting equipment, hydraulic pressure gauges, and precision measuring tools.

Drive System and Machine Access

Drive-system drawings identify the radiator, fuel tank, engine mounts, and pump coupling. Oil-cooler removal applies to the TB030 and TB035; the TB025 has no oil cooler.

Engine scope: The engine procedures cover removal and installation of the complete assembly. Internal Yanmar engine overhaul, including cylinder-head repair and head-bolt tightening sequences, is outside this manual's coverage.

Upper-frame procedures explain floor-frame removal, cabin handling, and access through the machine covers. Attachment sections cover pin connections and shim adjustment, supported by model-specific pin-and-bushing wear tables.

Pump, Valve, and Cylinder Repair

The pump chapters separate the gear-pump assemblies from the TB035 variable-piston assembly. The latter covers the rotary groups, swash plate, controller, and attached gear pump; the gear-pump section includes discharge-volume testing and inspection of housing contact marks.

Control-valve coverage extends to the TRASM circuit, main and port relief valves, anti-cavitation valves, and the sub control valve. Spools and section bodies are treated as matched components, with inspection criteria for deciding when section replacement is required.

Cylinder procedures distinguish the TB025 construction from the TB030/TB035 designs. They cover rod packing, piston packing, wear rings, cushion mechanisms, air bleeding, and internal and external leakage tests. Dimensioned insertion and corrective jigs support seal and bushing work.

The manual warns that omitting hydraulic-tank pressurization after hydraulic-unit installation can cause pump cavitation and shorten pump life. Before opening hydraulic fittings or beginning major service, verify residual-pressure conditions and follow the manual's shop-safety precautions.

Travel, Slew, and Hydraulic Fault Tracing

Travel-drive instructions cover the counterbalance valve, two-speed control, parking brake, and planetary reduction gears. The slew sections distinguish the standard motor from the parking-brake version, including its valve subassembly and hydraulic timer. Slew-bearing and swivel-joint removal, installation, and inspection are also covered.

Fault isolation: The boom-drift checks distinguish leakage inside the cylinder from leakage through the control valve. That distinction helps narrow the fault before either assembly is dismantled. Other charts address travel veering, failure to accelerate, weak slewing, excessive slew overrun, and attachment operation during travel.

Model-specific Hydraulic Circuit Diagrams show pump-to-actuator connections. Electrical Wiring Diagrams include wire-color tables and serial-specific changes. The Travel Motor Reduction Gear view, Cylinder Cushion Mechanism drawings, and slew-motor Brake Valve sections show the internal arrangements behind the diagnostic checks.

Performance Checks and Reference Tables

Performance inspection methods cover hydraulic pressures, cylinder speeds, travel, slew-bearing play, and crawler tension. Reference tables provide fluid capacities, recommended lubricants and service intervals, operating dimensions, rated lift capacities, and general and component-specific tightening torques.

A Preview of Pump Assembly Torque Data

These two examples are a small selection of the component-specific tightening data in the hydraulic-pump chapters.

For the TB025/TB030 gear-pump assembly, the assembly bolts are specified at 3.9–4.4 kgfm. In the TB035 chapter, the bolts attaching the gear pump to the main pump assembly are specified at 2.1–2.6 kgfm. The manual keeps these fastening points separate from pump-cover and relief-valve specifications.

PDF Search, Chapter Access, and Printing

Search and diagram detail: PDF text search is not available. Embedded bookmarks open the five main sections, with an additional cover bookmark. Small labels on the inspected electrical wiring diagrams are readable when enlarged.

Supplied as one printable, English-language, 362-page PDF. The total includes the original cover, foreword, contents page, five chapter dividers, and seven blank pages; these are already included in the page count.