Description

Komatsu D51EXi-24, D51PXi-24 2017 Workshop Manual

If you are turning wrenches on a D51EXi-24 or D51PXi-24 and find yourself guessing at a torque value or scratching your head over the DEF system, you are wasting billable time. That is why this Komatsu D51EXi-24, D51PXi-24 2017 Workshop Manual belongs on your shop tablet, not a third-party reprint. Aftermarket documentation leaves out critical safety steps and uses generic figures that do not match Komatsu’s actual hardware. I have seen guys snap head bolts because they trusted a copied PDF. This manual is the real deal—2967 pages of factory procedures, straight from the OEM.

Every time I crack this file open, I find something that saves me from pulling a part twice. The index starts on page 2, and the standard tightening torque table is right there in the foreword. No fishing around for specs. You want the charge pressure for the HST? It is buried in the cooling system section. But the manual’s bookmarks make it easy to find—no scrolling through 300 pages of random data.

Foreword, Safety, and Basic Information

Section 00 covers everything from how to read the shop manual to what to do if a fire starts. Komatsu does not assume you know when to disconnect a push-pull coupler or how to handle DEF fluid. The safety notice for operation, precautions for handling electrical equipment, and the actions taken to meet exhaust gas regulations are all spelled out. That is not fluff—that is factory liability wording. If you skip the part about storing AdBlue/DEF, you could end up with crystallized lines. The manual tells you exactly how to avoid that.

UREA SCR System: AdBlue/DEF Troubleshooting and Induction Strategy

Chapter 10 breaks down the urea SCR system in gory detail. You get the layout drawing, system diagram, function of the AdBlue/DEF system, and the inducement strategy that locks the machine down if the emissions system trips. The component parts section covers the mixing tube, SCR assembly, tank, pump, injector, and even the tank heating valve. Need to know how the system operating lamp system works? It is right there under BOOT-UP SYSTEM. That kind of specific breakdown is why this manual pays for itself on one repair.

3 Key Systems in the Engine System Section

The engine system chapter gives you the layout drawing, the engine control system diagram, and the function of the automatic idle stop system. Component parts include the damper, VGT, EGR system, EGR valve, EGR cooler, KCCV system, KCCV ventilator, and the KDOC. Each component has its own sub-section with disassembly and assembly procedures. For a machine that runs Tier 4 Final emissions, having the EGR and KCCV specs at your fingertips is non-negotiable. Aftermarket manuals often combine these into one vague paragraph. Not here.

Get the Right Torque Data from the Standard Tightening Torque Table

Torque specs are the difference between a leak-free repair and a comeback. The standard tightening torque table in the foreword lists values for bolts by class and diameter. But that is just the baseline. Many specific joints have their own torque listed in the relevant section. For example, the hydraulic oil cooler bypass and HST charge safety valve have separate torque calls. The manual also has a conversion table so you can switch between foot-pounds and Newton-meters without pulling out a calculator. You do not need to guess when you have the factory table open.

OEM Documentation: Why Third-Party Reprints Fail

I have compared this OEM file against aftermarket copies of the same model year. The differences are glaring. Missing pages in the safety section, blurred wiring diagrams, and torque values that do not match the actual hardware. This manual is a direct scan of the Komatsu publication, not a retyped version that lost the halftones. Every connector type—Deutsch, slide lock, push-pull—has its own illustrated procedure. The electrical wire code explanation is included. If you rely on a generic manual, you are taking a gamble on component damage. That is why I only use OEM documentation for any Manual Transmission rebuild or hydraulic system work.

Does This Manual Cover the Cooling Fan Control System?

Yes. Chapter 10 includes a dedicated section for the cooling fan control system with a system diagram and function description. The component parts cover the cooling fan motor, the hydraulic oil cooler bypass valve, and the HST charge safety valve. If you need to diagnose a fan that runs full speed all the time, the manual gives you the sensor values and the logic flow. That kind of detail keeps you from throwing parts at a problem.

Related Manuals for Komatsu Equipment

If you work on other Komatsu models, check these related OEM manuals:

• Komatsu WA65-5 WA70-5 WA80-5 2005 Workshop Manual
• Komatsu WH609-1E0 WH613-1E0 WH713-1E0 WH714H-1E0 WH716-1E0 Workshop Manual
• Komatsu PW95R-2 Workshop Manual – 520 Pages of Factory Specs

FAQ

Does this manual include the automatic idle stop system?

Yes. Section 10 under Engine System has a dedicated diagram and function description for the automatic idle stop system.

What makes this workshop manual better than a third-party reprint?

Third-party reprints often omit critical safety notices and use generic torque values that do not match Komatsu’s actual hardware. This 2017 OEM manual includes every page of the original publication—2967 pages covering everything from the urea SCR system to the electrical wire code. The safety precautions for handling DEF, hydraulic equipment, and fuel system components are all present. If you rely on a copied version, you risk missing the specific instructions for disconnecting Deutsch connectors or handling the AdBlue/DEF tank heating valve. That kind of omission leads to broken parts and wasted labor. With this file, you get the exact same documentation that Komatsu dealers use.

If you are serious about fixing these dozers the right way, stop chasing bad data. Access the Factory Manual and get back to work with the right specs in your hands.