1997 Liebherr A 900 / A 902 / A 912 / A 922 / A 932 Litronic Hydraulic Excavator Service Manual (P/N 8719164)

• Covers the Liebherr A 900, A 902, A 912, A 922, and A 932 Litronic hydraulic excavators in a 1,806-page PDF, publication Ident. No. 8719164.
• Hydraulic work includes LPVD double-pump commissioning and adjustment, A4V swing-pump pressure checks, control-valve troubleshooting, and hydraulic-cylinder removal and resealing.
• Electrical coverage distinguishes GLR and GLD horsepower controls, with component descriptions, horsepower-control fault tracing, automatic low-idle diagnosis, and serial-specific wiring diagrams.
• Mechanical sections cover SAT swing-drive removal and swing-brake repair, swing-ring replacement, and testing and adjustment data for 2 AVG 105 and 2 HL 100 two-speed travel gearboxes.
• Brake and chassis chapters address hydraulic brake pressure checks and bleeding, steering-system tests, and oscillating axle stabilizers, including automatic-control versions.
• Optional-equipment material covers overload-warning adjustment, load-holding valves, and AS 1, ASH, and AHS hydraulic attachment installations.
• Full overhauls use separate component publications for FMF/LMV motors, SAT swing gears, and axles. The engine chapter provides specifications and adjustments, not a complete engine-rebuild procedure.

Model, Serial-Number, and Engine Coverage

The cover lists update No. 8, dated November 28, 1997; individual sheets include March 1998 maintenance revisions. Coverage follows the model, machine type, and serial-number heading of each subgroup rather than a single model-year designation.

A 900 engine specifications identify the Deutz BF 4 L 913 from S/N 101 and BF 4 M 1013 E from S/N 4001. Separate A 902 Industrie data and maintenance sections begin at S/N 3046. Liebherr D 904/D 914 and D 924 E engine variants have their own specification tables.

Engine torque, wear-limit, and valve-clearance data accompany speed-adjustment and sensor-controlled low-idle sections.

Hydraulic Circuits and Mechanical Repair

The A 932 closed swing circuit has a dedicated filtration procedure after pump or motor failure: its oil does not pass through the excavator's return filter. Working-hydraulic sections address spool-travel checks, internal leakage, pressure cut-off, and servo-control adjustment. Fault-finding instructions distinguish control-valve problems from faults in pumps, relief valves, cylinders, and motors.

The A 932's PVG 350 B 381 splitterbox has its own removal, disassembly, inspection, and reassembly instructions, separate from the travel gearbox. Axle sections distinguish AP/APL-B and Kessler assemblies and disc- versus drum-brake configurations, with removal and installation instructions, sectional drawings, and bearing-adjustment data.

A 932 four-wheel steering is covered with and without crab steering, including leakage-equalization procedures for the two steering axles.

The A 902 aluminum-segment coupling carries a specific assembly warning: twisting a segment can loosen its mounting screws and destroy the coupling. Repair-welding guidance covers machine and attachment structures; the undercarriage/uppercarriage section adds expander-pin joints.

Cab Systems, Attachments, and Diagnostic Drawings

Special installations extend to height-adjustable cabs, quick-change adapters, and centralized lubrication. Cab coverage identifies D 1 LC and D 3 LC heaters and the D 5 W supplementary heater. KONVEKTA air-conditioning material includes troubleshooting, evacuation and charging instructions, plus R12/R134a identification and changeover cautions.

Electrical drawings trace GLR/GLD horsepower control, sensor-controlled automatic low idle, and the KONVEKTA air-conditioning system. Hydraulic schematics show the closed swing loop and automatic oscillating-axle stabilization.

Torque Tables, Tolerances, and Service Tools

Technical data includes torque tables for Ermeto couplings and standard and fine metric hardware. ISO tolerance charts for shafts and bores are supplemented by fluid-capacity, lubricant, hydraulic-pressure, leakage, and electrical-test specifications.

Special-tool tables identify the horsepower-control tester 6202698 and spool-travel measuring tool 8007363, along with application drawings and fabrication details for selected fixtures. Connector repair tooling is identified for CA-COM, SURE-SEAL, and Deutsch DT systems.

Operating instructions belong to the separate Operation and Maintenance Manual. Technicians must review the factory pressure-relief, lifting, and machine-support precautions before working on hydraulic circuits, raised attachments, or suspended assemblies.