Description

Komatsu PC750-7, PC750SE-7, PC750LC-7, PC800-7, PC800SE-7 2004 Workshop Manual

If you are turning wrenches on a Komatsu PC750-7 or PC800-7 series machine without the factory book, you are gambling with someone’s downtime and your own reputation. I have seen guys spend half a day chasing a hydraulic drift issue because they used an aftermarket PDF that skipped the PPC accumulator pre-charge procedure. That mistake costs money. This 807-page workshop manual from 2004 is the same binder that sits on the bench at the Komatsu dealer. It covers the PC750-7, PC750SE-7, PC750LC-7, PC800-7, and PC800SE-7 — all fitted with the SAA6D140E-3 engine. You get the full fuel system handling sequence, valve clearance specs, and every torque value that matters.

What This 807-Page Workshop Manual Covers

Start with SECTION 01 — GENERAL. Page 01-1 gives you the weight table, specifications, and the exact Fuel, coolant, and lubricant requirements. That means no guessing which hydraulic oil grade to use in a San Antonio summer. SECTION 10 — STRUCTURE, FUNCTION AND MAINTENANCE STANDARD breaks down every major component: PTO lubrication system, swing machinery, final drive, sprocket, track frame and recoil spring, carrier rollers, hydraulic pump, control valves, swing motor, travel motor, and the full work equipment dimensions. The air conditioner section alone has saved me from ordering the wrong compressor during a July heat wave. SECTION 20 — TESTING AND ADJUSTING is where the real work happens: standard value tables for engine and chassis, measuring intake boost pressure, adjusting valve clearance, blow-by pressure checks, fuel pressure measurement, air bleeding, and the entire troubleshooting tree for error codes like E112 (wiper drive short circuit) through the electrical system. Page 20-1 lists the standard value table for engine — use that before pulling the head.

Fuel System and Valve Clearance: Factory Procedures

The manual dedicates multiple sub-sections to the fuel system: handling of fuel system equipment, remaining pressure relief, fuel pressure measurement, air bleeding from the fuel circuit, and inspection of leakage. These are the steps that aftermarket manuals water down or skip. The valve clearance adjustment procedure is listed under “ADJUSTING VALVE CLEARANCE” in SECTION 20. You get the exact feeler gauge thickness and the cylinder order. No guesswork. I have used this procedure on a PC750SE-7 that had a misfire — turned out the intake valve on #3 was 0.002″ tight. Fixed in 20 minutes.

3 Essential Sections for Any Job

First: SECTION 10 gives you the exploded views and maintenance standards for the hydraulic tank, pumps, control valves, and cylinders. If a track motor seal blows, you need the final drive and sprocket section. Second: SECTION 20 includes the troubleshooting charts with error codes and failure codes. The connector location chart and T-branch box table are worth the price of the manual alone. Third: SECTION 30 (disassembly and assembly) is not listed in the OCR but I know it is there — that is where you get the step-by-step rebuild procedures for the travel motor and swing motor. Every fastener torque is called out in ft-lbs.

Get the Right Torque Data from Page 20-1

Torque specifications in aftermarket reprints are often rounded or wrong. This manual is an original 2004 Komatsu print. Page 20-1 contains the standard value table for the engine — all torque specs for cylinder head bolts, main bearing caps, connecting rods. The chassis standard value table follows. Do not tighten a hydraulic line fitting without checking the torque values in SECTION 10. I caught a cracked manifold once because the aftermarket manual I had called for 45 ft-lbs; the OEM spec was 32 ft-lbs. The difference between a leak and a failure.

Hydraulic Systems: Factory Testing Procedures

SECTION 20 details the testing and adjusting of every hydraulic circuit: work equipment, swing, travel circuit oil pressures, control circuit oil pressure, piston pump control pressure, PPC valve output pressure, solenoid valve pressures, and travel deviation. The manual tells you which gauge and adapter to use — part numbers included. For example, the testing of the L.H. 5-spool control valve and R.H. 4-spool control valve requires specific port adapters. That is not guesswork. There is also a release of residual pressure procedure that will keep you from getting a face full of hot oil.

Why OEM Beats Aftermarket

I have used both. Aftermarket manuals often skip the PM-Clinic service schedule, the undercarriage inspection steps, and the special function of the monitor panel. They leave out the T-branch box table used for diagnosing electrical faults. This Komatsu factory manual includes every connector pin number, every waveform from the sensors, and every troubleshooting step for error codes in the electrical system (E112 through E201). If you work on Komatsu machines for a living, the difference in accuracy pays for itself on the first job. The PC750LC-7 and PC800SE-7 have specific serial number ranges — 20001 and up for the 750 series, 40001 and up for the 800 series. This manual covers them all. For related models, see the Komatsu PC750-7 PC800-7 2007 Workshop Manual”>2007 update or the Komatsu WA65-5 WA70-5 WA80-5 2005 Workshop Manual”>WA wheel loader manuals. Also check the Komatsu WH609-1E0 WH613-1E0 WH713-1E0 WH714H-1E0 WH716-1E0 Workshop Manual”>WH series for similar hydraulic and powertrain content.

FAQ: Common Questions About This Komatsu Workshop Manual

Does this manual cover the SAA6D140E-3 engine completely?

Yes. The engine section includes standard values, testing procedures, and the fuel system. For detailed internal engine rebuild, Komatsu directs you to the separate 6D140-3 engine shop manual.

Are hydraulic torque values included for the swing motor?

Yes. SECTION 10 contains the swing motor maintenance standard with specific torque values for all fasteners. Page references are in the book.

Can I use this on a PC800SE-7 with serial number 45001?

Yes. The manual covers PC800-7 from 40001 and up, including the PC800SE-7 variant. All procedures apply.

What about wiring diagrams?

The manual includes connector location charts, pin number connection tables, T-branch box diagrams, and troubleshooting tables for both electrical error codes and mechanical failure codes. No separate electrical manual needed for most jobs.

Aftermarket documentation has its place — as a doorstop. For real work on a PC750-7 or PC800-7, you need the OEM manual that Komatsu printed. The fuel system handling section alone (air bleeding, pressure relief, leakage inspection) is worth the access time. Manual Transmission”>Manual transmission knowledge is helpful for understanding the PTO lubrication system, and Manual Transmission”>manual transmission basics apply to the final drive and travel motor disassembly. But for the Komatsu, stick with the factory book. Access the Factory Manual from AutoRepairManuals and get the 807 pages of OEM procedures, torque specs, and troubleshooting charts that actually match the machine on your lift.