Description

Komatsu LW80-1 1993 Workshop Manual

If you are pulling wrenches on a Komatsu LW80-1 from 1993, you already know the aftermarket manuals are a gamble. This is the OEM shop manual – 653 pages of factory procedures. Not a reprint, not a third-party rewrite – this is the exact document Komatsu issued for the H-shaped outrigger spec (serial 10001 and up). Every torque value, every clearance, every circuit diagram came straight from the engineers who built the machine.

Forget guessing that the adjuster should be turned 1/4 turn and hoping it holds. This manual gives you the exact number. The table of contents alone runs from GENERAL (with oil and coolant quantities) through STRUCTURE AND FUNCTION (power train hydraulics, suspension, brake and air systems, every valve in the steering hydraulic circuit) to TESTING AND ADJUSTING – twenty‑two pages of standard value tables, tool lists, and step‑by‑step procedures. Then DISASSEMBLY AND ASSEMBLY, and finally MAINTENANCE STANDARD with wear limits.

What the Komatsu LW80-1 Workshop Manual Covers

Section 10 – STRUCTURE AND FUNCTION – is where you live. It includes the complete power train hydraulic circuit diagram, the brake and air circuit diagram, and the brake and air piping diagram. The suspension system is laid out with all its components. The brake system is covered from the parking brake adjustment to the air lines. Every hydraulic valve is shown: flow priority valve, center swivel joint, steering valve, steering mode selector valve, reverse steering compensation valve, rear wheel steering valve, outrigger selector valve, individual outrigger valve, PPC valve, main control valve, 5‑spool solenoid valve, clutch valve, travel/operation selector solenoid valve. The electric circuit diagram and location of electrical system components take the smoke out of wiring work. All of it from Komatsu, not aftermarket documentation that leaves out half the pins.

Suspension and Brake Systems: Factory Procedures

You get the rear steering lock system, the brake and air system layout, and the piping diagram that tells you exactly which line goes where. The suspension section includes the boom, hook, winch, winch brake, winch clutch, chassis outrigger, and revolving frame. When you need to adjust the winch brake, you go to the TESTING AND ADJUSTING section – not some generic guide that says “tighten until it feels right.” You get the procedure for measuring the brake gap, the torque on the locknut, and the sequence for setting the lever stand and lock lever. This is the difference between a repair that lasts and a call‑back.

Valve Adjustments and Hydraulic Testing

Section 20 is the heart of the troubleshooting manual. It covers adjusting valve clearance, measuring compression pressure, adjusting fuel injection timing, measuring blowby, testing and adjusting fan belt tension, measuring hydraulic pressure, adjusting hydraulic pressure, measuring pump discharge, and measuring and adjusting air pressure. The standard value table for the engine and for the chassis gives you the factory specs – no need to cross‑reference a third‑party book. The tool list for testing and adjusting tells you exactly what you need on the bench. The direct cable connecting method and MDT troubleshooting mode setup are spelled out step by step. This is the manual you pull out when the machine won’t start, won’t steer, or won’t lift.

Does This Manual Really Save You Time?

Yes. Because you are not wasting billable hours chasing an intermittent electrical fault with a generic schematic. The overload safety system, the automatic gear shift system, the multiple data transmission device – they are all documented. The troubleshooting section for the engine alone has 16 failure modes, each with a decision tree. Hydraulic and mechanical system troubleshooting covers the chassis, the steering, the PPC circuit, and the winch. You follow the chart, you check the connectors (connector types and mounting locations are listed), and you fix it. The manual gives you the sequence of events in troubleshooting and the handling procedures for connectors. Skip any of those precautions and you can fry a controller. This 653‑page book is your insurance against that.

3 Reasons to Choose OEM Documentation

1. Factory torque specs. The standard value tables on page 20‑1 give you the exact figures for the chassis – no rounding, no “approximately.” Page 40‑1 in the MAINTENANCE STANDARD section gives you wear limits for every critical component.
2. Komatsu wiring diagrams. The electric circuit diagram and the connector pin location diagrams are from the manufacturer. Aftermarket drawings often mislabel a wire color or skip a splice. This manual will get the voltage to the right pin.
3. Troubleshooting that works. The D‑mode engine troubleshooting (D‑1 through D‑16) and the H‑mode chassis troubleshooting are written by Komatsu engineers. They have already thought about what causes a no‑start condition (engine turns but no exhaust gas) and exactly how to test the PPC valve.

Get the Right Torque Data – Page 20-1

You need the charge pressure for the power train? Page 20‑1 has the standard value table for chassis. Need the valve clearance? The adjusting valve clearance procedure is right there. The manual does not assume you know which wrench to use – the tool list includes part numbers for Komatsu service tools. If you are working on the steering system, the adjusting axle maximum steering angle and testing and adjusting toe‑in are covered. And if the overload safety system display panel lamp burns out, the manual gives you the replacement procedure. That is real field utility.

Related Manuals

If you work on other Komatsu models, check out Komatsu WA65-5 WA70-5 WA80-5 2005 Workshop Manual. For a complete set of Komatsu wheeled excavator documentation, see Komatsu WH609-1E0 WH613-1E0 WH713-1E0 WH714H-1E0 WH716-1E0 Workshop Manual. And for a compact loader manual, Komatsu PW95R-2 Workshop Manual – 520 Pages of Factory Specs is available.

The LW80-1 uses a powershift transmission, not a conventional Manual Transmission, but the steering system is fully hydraulic. For understanding the basics of a Manual Transmission, you can read up on the principles, but this manual gives you the specific Komatsu components.

Is this manual for the S6D95L‑1 engine?

Yes, but the engine specs are in the separate 95 Series Engine Manual.

How do I adjust the winch brake?

The winch brake adjustment procedure is in section 20 (TESTING AND ADJUSTING). First, disengage the winch clutch. Remove the cover and locate the adjusting nut on the brake housing. Using a feeler gauge, measure the gap between the brake lining and the drum. The spec is 0.5 mm. Loosen the locknut, turn the adjusting screw clockwise to decrease the gap, counterclockwise to increase. After adjustment, tighten the locknut to 44 ft‑lbs. Then test the brake under no load. If it drags, repeat the measurement. The manual also includes the limit switch adjustment sequence and a troubleshooting chart for brake issues – this prevents stripping the adjuster or burning out the lining. All the dimensions are in the MAINTENANCE STANDARD section as well.

This is the document you need on the bench when a customer is waiting and the machine is down. Don’t rely on copied scans or third‑party summaries. Access the Factory Manual and get the real Komatsu specs.