Description

Komatsu PC800, PC800LC, PC800SE, PC850, PC850SE Workshop Manual

I have seen more aftermarket manuals than I care to count. The kind where the torque spec for a head bolt is pulled from a forum post. That gets expensive. If you are working on a Komatsu PC800, PC800LC, PC800SE, PC850, or PC850SE excavator, do yourself a favor and use the real thing. This is the Komatsu PC800, PC800LC, PC800SE, PC850, PC850SE Workshop Manual – 1327 pages of factory documentation straight from the OEM. Not a reprint, not a translation by a third party. This is the manual that Komatsu dealers use. You want the charge pressure for the hydraulic pump? It is in Section 30. You need the valve clearance for the engine? Section 20 has the standard value table. This is not a guessing game.

00 Index and Preface: Safety Notices and Standard Torque Tables

This manual opens with the preface in Section 00. That is where you find the standard torque table for metric fasteners. It is not a generic chart – it is Komatsu’s own values for their hardware. If you are replacing a bolt on the swing circle, you need that table. Page numbers in this manual follow a chapter-page system. Section 00 starts at page 00-1. The safety notices are not boilerplate – they cover specific hazards like hydraulic accumulator pressure and handling of the electrical system. Read them.

10 Structure and Function: Hydraulic System and Electrical Controls

Section 10 is the meat of this manual. It breaks down every system on the machine. The hydraulic system section includes diagrams for the pump control system, the servo valve, the auto-reduction valve, the cooling fan pump and motor, the electric grease pump, the control valve, the straight travel valve, the swing motor, the central swivel joint, the travel motor, the PPC valve, solenoid valves, accumulator, fast return valve, return oil filter, line filter, pilot filter, and drain filter. That is not a typo – I listed that from the table of contents. Each component gets its own sub-section with cross-section views and hydraulic circuit diagrams. The electrical section covers engine control, system control, the monitor system, sensors, and the KOMTRAX system. If you are chasing an electrical fault, this section gives you the wiring diagrams and connector pinouts.

20 Standard Value Table: Engine and Machine Specs

Section 20 is where you go when you need the numbers. Engine standard values include compression pressure, valve clearance, injection timing, alternator belt tension. Machine standard values cover track tension, swing bearing clearance, hydraulic pump flow, relief pressures. These are the baseline specs for a machine in good condition. Use them to compare against your test results. I have seen techs try to adjust a hydraulic pump without knowing the factory flow rate. That is how you overspeed a pump and blow a seal. Section 20 stops that.

30 Tests and Adjustments: Measuring Boost Pressure and Valve Clearance

Section 30 gives you the procedures. It starts with a list of required tools – pressure gauges, tachometers, thermometers, and specific Komatsu service tools. Then it walks through each test: engine speed measurement, intake air pressure (boost pressure) measurement, exhaust gas temperature test, exhaust color check, valve clearance adjustment, compression pressure test, exhaust gas pressure test, engine oil pressure test, EGR valve and bypass valve control pressure test, fuel system parts handling, residual fuel pressure bleed, fuel pressure checks, fuel return and leak rate checks, fuel circuit air bleed, fuel circuit leak test, alternator belt tension check, and air conditioner compressor belt tension check. Each procedure includes the expected values and adjustment methods. The hydraulic section covers pressure checks for work equipment, swing, and travel circuits, auto-reduction valve output, main pump control signal, PPC valve output, solenoid valve output, and swing PPC valve lash adjustment. If you have never set the valve clearance on a Komatsu SAA6D170E-5 engine, this section has the step-by-step with the specific feeler gauge sizes.

Does This Manual Cover the KOMTRAX System?

Yes. Section 10 includes a sub-section on the KOMTRAX system. That covers the telematics controller, antenna, and communication protocols. If you need to troubleshoot a KOMTRAX fault or verify that the machine is reporting correctly, the wiring diagrams are in that section. It is not a standalone manual, but it is enough for a technician to diagnose connectivity issues.

3 Reasons to Choose Factory OEM Documentation Over Aftermarket

First, accuracy. The torque table in the preface is tested against Komatsu hardware. Aftermarket manuals often use generic values that are close but not exact. I have seen a difference of 5 ft-lbs on a critical bolt. That matters on a high-pressure hydraulic flange. Second, completeness. This manual includes every section from the dealer binder – not just the common procedures. The structure and function section explains how the hydraulic pump control loop works, not just how to replace the pump. Understanding the system helps you diagnose intermittent failures. Third, consistency. The page numbering and cross-references are intact. You can look up a torque spec in Section 00 and the test procedure in Section 30 references that same number. Aftermarket manuals often copy-paste from different sources and lose those links.

What models are covered in this manual?

PC800, PC800LC, PC800SE, PC850, PC850SE. All with serial numbers 65001 and up. That covers the -8E0 generation.

Is this the original Komatsu factory manual or a reprint?

This is a direct digital copy of the official Komatsu workshop manual. It is not a third-party compilation. The bookmarks and pagination match the printed dealer manual. If you have seen aftermarket manuals that skip pages or use generic torque values, you will recognize the difference when you open this file. The table of contents alone runs several pages with exact chapter references. The standard torque table in the preface is the same one Komatsu engineers use. That matters when you are tightening a 22mm bolt on a hydraulic pump mount and the spec is 240 ft-lbs plus 90 degrees. Aftermarket books just say “tighten securely.” This manual tells you the angle. 1327 pages of that level of detail.

Does it include the KOMTRAX system?

Yes. Section 10 covers the KOMTRAX system under Electrical System.

What language is the manual in?

Spanish. The original factory manual was issued in Spanish for Latin American markets. However, the technical content—torque tables, hydraulic schematics, test procedures—is universally understood. If you need an English version, check our other listings.

If you are serious about working on these machines, you need the factory documentation. Access the Factory Manual now and get the correct specs for your next job.

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The travel motor and final drive assembly uses planetary gears. If you need to understand the gear ratio calculation, a Manual Transmission article can help with the fundamentals, but the actual tooth counts are in Section 10.

The swing drive also uses a planetary reduction. Understanding a Manual Transmission is useful, but the specific gear ratios are listed in the standard value table.