Description

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

If you’re wrenching on a Komatsu PC800, PC800LC, PC800SE, PC850, PC850SE hydraulic excavator and you don’t have the factory Service Manual in your hand, you’re guessing. And guessing on a 50-ton machine with a $30,000 engine rebuild bill? That’s a fast way to blow up your budget and your reputation. I’ve seen techs torque head bolts by feel and wonder why the engine leaks at 500 hours. Don’t be that guy. This manual is the original OEM document—325 pages of what Komatsu actually wants you to do, not some aftermarket rewrite that skips the critical steps.

Before you even crack a wrench, this manual makes you read the safety section. Page 1 tells you exactly where to find your serial number plate and PIN. You’ll know which machine variant you have—PC800, PC800LC, PC800SE, PC850, or PC850SE—because the torque specs and maintenance intervals change between models. The manual is built around real shop use: step-by-step procedures, required tool lists, OEM torque specifications, and workshop tips that keep you out of trouble.

What You Get in This OEM Service Manual

The table of contents covers everything from FOREWORD and SAFETY through OPERATION, MAINTENANCE, and SPECIFICATIONS. You get the full MAINTENANCE chapter with interval schedules from initial 100 hours all the way up to every 8000 hours. There’s a dedicated TIGHTENING TORQUE SPECIFICATIONS section—because torquing a track frame bolt to the wrong value on a PC850SE will cost you a walkaround. The manual includes WEAR PARTS LIST, SAFETY CRITICAL PARTS LIST, and recommended fuel, coolant, and lubricant tables. All in imperial units, by the way—no metric-to-imperial conversion guesses.

Safety Information: Not Optional

The safety section is 30+ pages. That’s not padding; that’s the difference between walking off the job site and being carried off. The manual covers fire prevention, precautions for getting on/off the machine, protective structures, and what to do when running the engine inside a building. If you’ve ever seen a hydraulic line blow at 3000 psi, you know why the PRECAUTIONS FOR MAINTENANCE chapter exists. The manual tells you exactly how to relieve pressure before you crack a fitting. No shortcuts.

Engine and Systems Covered

This manual covers the entire machine—hydraulic system, engine, undercarriage, electrical, and operator cab. The engine section is buried inside the MAINTENANCE procedures because Komatsu expects you to follow the scheduled services. You’ll find step-by-step for checking before starting, every 10-hour, 250-hour, 500-hour, 1000-hour, 2000-hour, 4000-hour, 5000-hour, and 8000-hour maintenance. Each procedure lists the tools you need, the torque values, and the fluid capacities. For example, the SAE 15W-40 oil capacity for the engine is listed in the recommended lubricant table—no need to call the dealer.

For related models, see the Komatsu PC800/PC850 Workshop Manual. If you need field assembly instructions, the Komatsu PC800/PC850 Field Assembly Instruction covers that. For earlier models, check Komatsu PC750/PC800-6 Workshop Manual.

Torque Specs and Fluid Capacities

The TIGHTENING TORQUE LIST in the MAINTENANCE chapter gives you the exact ft-lb values for every critical fastener: engine mounting bolts, track frame bolts, hydraulic pump flange bolts, swing motor bolts. You don’t need to hunt through five different aftermarket PDFs that contradict each other. This manual also includes the tightening torque for safety critical parts—those are the bolts that, if they come loose, kill someone. I’ve seen aftermarket manuals list values that are 20% off. Not here.

Fluid capacities are in gallons and quarts. The recommended brands and quality standards for oil, coolant, and hydraulic fluid are listed with Komatsu part numbers. If you use the wrong spec hydraulic oil in a PC850SE, the pump won’t last 500 hours. The manual saves you that grief.

Who Needs This Manual?

DIY mechanics, equipment owners, home garage enthusiasts, and beginner technicians who want to do the job right the first time. If you own a PC800LC or a PC850 and you’re planning to do your own 1000-hour service, you need this manual. It tells you which filters to change, how to bleed the fuel system, and how to check the swing brake. The troubleshooting section covers common problems like “running out of fuel” and “discharged battery” with step-by-step diagnostics. General knowledge of Manual Transmission systems can be helpful when troubleshooting drivetrain issues, but this manual focuses on the hydraulic drivetrain. See Manual Transmission resources for additional theory on gearboxes.

Why OEM Beats Aftermarket

I’ve been torquing bolts for 28 years. Aftermarket manuals are cut-and-paste jobs with missing pages and wrong torque specs. This is the real factory document—scanned from the original Komatsu print, not a reprint or a third-party rewrite. The diagrams are clear, the wiring schematics (if included) are accurate, and the safety warnings are not watered down. You’re paying for peace of mind that the information matches what the dealer’s techs use. That’s worth the price of the manual on the first job alone.

Is this manual the same as the one that comes with a new machine?

Yes. This is the exact OEM Operation & Maintenance Manual Komatsu provides with the PC800-8R, PC800LC-8R, PC800SE-8R, PC850-8R, and PC850SE-8R series. It includes all safety labels, maintenance schedules, and specifications.

Does it include engine rebuild procedures?

This manual covers operation, maintenance, and troubleshooting. For full engine disassembly and overhaul, you need the separate Shop Manual (which covers the SAA6D170E-5 engine). The OEM Service Manual provides the maintenance schedule and torque specs needed to keep the engine running, but not internal rebuild steps. If you’re pulling the head, you’ll want the full workshop manual.

You’ve read through the details. You know the manual exists. Now get it on your shop tablet or printed binder. Access the Factory Manual and stop leaving your Komatsu’s reliability to chance.