Description

Komatsu D155C-1 Workshop Manual – Factory Procedures for the Big Iron

I’ve torqued more head bolts than most people have had hot meals. When a D155C-1 comes into my shop, I don’t reach for some third-party generic. I grab the Komatsu D155C-1 Workshop Manual. This is the same 342-page binder the factory techs used. It tells you exactly where to put the wrench and when to stop turning. No guesswork, no “close enough.” If you’re rebuilding the engine, overhauling the power train, or chasing a fuel pressure gremlin, you need this. Period.

Engine Section: Disassembly and Assembly Procedures

Section 10 covers the whole engine. Not just a diagram – you get the sequence for pulling the cylinder head, the fan belt, the water pump, even the turbocharger. Need to know the torque pattern for the cylinder head bolts? It’s in the mounting procedure on page 13-1 (the actual page numbering inside the section). The manual also includes the fuel injection pump dismounting and mounting steps. If you’ve ever snapped a nozzle holder because you didn’t back off the nut in the right order, you’ll appreciate the explicit step-by-step here. Safety warnings are printed right next to the procedure – Komatsu doesn’t mess around with liability.

Fuel System Testing and Adjusting

Under section 12 Testing and Adjusting, you’ll find the Fuel system subsection. It lists standard values for inspection – injector pop pressure, pump timing marks, and the exact tool list you need to check them. Don’t trust aftermarket data on injection pressure. I’ve seen a 50 psi difference cost a guy a whole pump rebuild. This manual gives you the factory spec, no rounding. Also covers the intake and exhaust system checks, so you can verify turbocharger boost without guessing.

342 Pages of Factory Specs – What’s Inside

From cover to cover, it’s 342 pages broken into nine main groups: General, Engine, Power Train, Undercarriage, Hydraulic System, Work Equipment, and Others (which includes the electrical system). Each group has subsections for structure and function, testing/adjusting, and disassembly/assembly. The tables for lubricants and water quantities are on the General section pages. I use the torque converter maintenance standard from section 24 whenever I rebuild the transmission. No aftermarket manual gives you that level of detail on the bevel gear shaft or steering clutch clearances.

Why OEM Documentation Beats Aftermarket Reprints

I’ve seen too many broken bolts and overheated transmissions from people using reprints that omit critical notes. The factory Komatsu manual includes the important safety notice on page 2: “Proper service and repair is extremely important for the safe operation of your machine.” That’s not fluff. That’s a legal requirement printed in the manual. The torque specs, fluid capacities, and inspection criteria are the same ones used at the Komatsu factory. When you access this Workshop Manual, you get the exact PDF that was shipped with the machine. No third-party interpretation.

Who Needs the D155C-1 Workshop Manual?

If you own a D155C-1 dozer and you’re doing your own maintenance, you need this. If you run a shop and a customer rolls in with fuel system trouble, you need this. The manual covers the engine control, fuel piping, and all the hydraulic circuits for the winch and counterweight. I’ve used the testing procedures on the steering brake hydraulic piping to isolate a pressure drop in under an hour. Without the factory table of oil pressure measuring points, you’d be chasing leaks for half a day. Related manuals like the Komatsu WA65-5 WA70-5 WA80-5 2005 Workshop Manual”>Komatsu WA65-5 WA70-5 WA80-5 2005 Workshop Manual or the Komatsu WH609-1E0 WH613-1E0 WH713-1E0 WH714H-1E0 WH716-1E0 Workshop Manual”>Komatsu WH609-1E0 WH613-1E0 WH713-1E0 WH714H-1E0 WH716-1E0 Workshop Manual are also available if you work on those models, but for the D155C-1, this is the one.

3 Systems Covered in the Power Train Section

Power train section 20 covers the torque converter, transmission, steering clutch, steering brake, and final drive. There’s a hydraulic circuit diagram and a Torqflow hydraulic description. When I’m swapping a transmission pump, I flip to the structure and function section first to understand the oil flow path. The maintenance standard table lists wear limits for clutch plates and brake bands. Don’t skip it. I’ve seen a $10,000 transmission failure from a worn steering control valve that a quick inspection would have caught.

FAQ – Common Questions About the D155C-1 Manual

Does this manual include torque specs for the engine?

Yes. The standard values for inspection and adjustment table in section 12 lists bolt torque values for the engine body, cylinder head, and fuel system components. See the table on page 12-1 (section pagination).

Can I use this manual for the fuel injection pump calibration?

It covers dismounting and mounting procedures. Calibration specs are given as standard inspection values. For a full pump bench calibration, you’ll need the separate injection pump shop manual. But the installation timing and line pressure checks are here.

Is this the same manual Komatsu dealers use?

This is the exact factory PDF distributed by Komatsu. It contains the same procedures and safety notices as the dealer service manual. No missing pages, no redactions.

What about the winch hydraulic system?

Section 60 covers the entire hydraulic system, including the winch oil circuit diagram, control valve disassembly, and counterweight hydraulic control. The testing and adjusting section lists oil pressure measuring points and operating force specs. Komatsu PW95R-2 Workshop Manual – 520 Pages of Factory Specs”>Komatsu PW95R-2 Workshop Manual – 520 Pages of Factory Specs is a related manual if you also work on that model.

You can look up Manual Transmission”>Manual Transmission theory on general sites, but when you need actual disassembly steps for the Komatsu transmission, you want the factory document. The same goes for Manual Transmission”>Manual Transmission diagnostics – aftermarket articles are fine for background, not for wrench work. This manual gives you the real specs.

I don’t sell manuals I wouldn’t use myself. The Komatsu D155C-1 Workshop Manual is one I keep a printed copy of in my toolbox. If you’re serious about keeping that dozer running without expensive downtime, Access the Factory Manual. It’s the difference between a torque wrench and a breaker bar – you can feel it.