Description

Komatsu 170E-5 Workshop Manual – What You’re Getting

I’ve seen too many guys rebuild an engine with aftermarket specs, then wonder why the liner protrusion is off or the injector return rate is wrong. You don’t get do-overs on a 170E-5 Series. If you’re pulling the cylinder head on one of these Komatsu engines, you need the Komatsu 170E-5 Workshop Manual — the one with 687 pages of factory-verified data, not some scanned copy from a third party that’s missing the critical pages. This manual is the same document the dealer techs use, and it covers everything from the CRI fuel system to the gear train backlash values. Page numbers and section titles in this review come straight from the SEN00190-13 file. No guesswork, no generic diagrams.

7 Systems Covered – From Air Cleaner to Engine Controller

The manual is split into sections that match how a real shop breaks down a job. Section 10 covers structure, function, and maintenance standard in two parts. Part 1 goes through the cylinder head, main moving parts, crankshaft, camshaft, connecting rods, piston rings, flywheel, vibration damper, timing gear, valve system, and the crosshead. Part 2 dives into the lubrication system (oil pump, filter, cooler), the fuel system with the CRI diagram, the cooling system (water pump, thermostat, fan drive), and the electrical equipment (alternator, starter motor, starting aid, engine controller). You get the factory diagrams for oil flow and fuel routing — not artist renderings.

Testing and Adjusting – With and Without EGR

Section 30 is where the manual earns its keep. It devotes separate subsections to the EGR-equipped version and the EGR-less version of the 170E-5. Each subsection includes a full list of required special tools (with sketches), then walks through testing air boost pressure, exhaust temperature, compression pressure, blow-by pressure, oil pressure, and EGR drive oil pressure. You also get procedures for releasing residual fuel pressure, testing return rate from the injector, bleeding air from the fuel circuit, and handling the controller voltage circuit. That’s the kind of depth that keeps you from chasing a non-existent vacuum leak when the real problem is a bad injector return.

Why OEM Matters – Not Aftermarket

Aftermarket manuals often skip the standard torque table in the foreword or reprint a generic conversion chart. This Komatsu manual includes a Standard tightening torque table and a Conversion table in the foreword. Also in Section 00 you get the full safety notice, handling instructions for electric equipment and hydraulic components, the electric wire code, and the push-pull coupler procedure. You don’t get that from a $9 PDF on a forum. If you need the exact charge air pressure sensor high error code (E-3, code [122/CA122]), the troubleshooting table in Section 40 tells you the possible causes and the test steps. That’s factory-original information, not a mechanic’s guess.

Standard Value Table – The Specs You Can’t Fake

Section 20 lists the standard service value table for testing, adjusting, and troubleshooting. It also includes the running-in standard and performance test standard. When you’re setting valve clearance or verifying compression pressure, you reference that table. No need to call a buddy who worked on one five years ago.

I’ve used this manual to diagnose a no-injection cranking condition on a 170E-5 that had the shop stumped for two days. The fuel pressure test procedure on page 73 (approximate, depending on your binder setup) gave me the exact steps to check the pressure limiter leak and injector return rate. That alone paid for the manual.

Does This Manual Cover the CRI Fuel System?

Yes. The table of contents lists “CRI system diagram” and “Outline of CRI system” under the fuel system section. It includes the fuel filter, electric priming pump, and engine controller cooler. If you’re working on common-rail injection, this is the document you need.

Wiring Diagrams and Connector Information

Section 40 includes a connection table for connector pin numbers and a T-branch box / T-branch adapter table. You can trace the exact circuit for the engine controller internal failure code E-1 [111/CA111]. The manual also explains how to read electric wire codes and handle connectors. That’s critical when you’re probing a harness without shorting a pin.

What’s Not in the Manual

This is strictly the engine workshop manual for the 170E-5 Series. It does not cover the machine chassis, hydraulic system, or transmission. For transmission work, you’ll want a separate Manual Transmission manual. But if you’re rebuilding the engine, replacing injectors, or diagnosing a no-start, this is the only source you should trust.

Does this manual cover the EGR-less version of the 170E-5?

Yes. Section 30 has a dedicated subsection titled “Testing and adjusting (EGR-less)” with its own tool list and procedures.

How many pages are in this manual?

687 pages.

Can I use this manual for a Komatsu 170E-5 Series that has different injection timing?

The specification section (Section 01) includes engine performance curves and a weight table. If your engine has been modified, the standard value table in Section 20 will help you compare against factory specs. For engines that must meet specific emission standards, the troubleshooting section also covers error codes related to the EGR and bypass valve.

Where can I check the torque for the cylinder head bolts?

The standard tightening torque table is in Section 00, foreword and general information. The manual does not list a specific page number for head bolts because it varies by the component, but the table covers the fastener classes you will encounter.

You’ve read the breakdown. If you’re serious about working on a Komatsu 170E-5 engine — whether it’s a marine, generator, or industrial application — get the actual OEM documentation. Don’t rely on a copied PDF that’s missing pages. Access the Factory Manual and keep it on your shop tablet or printed binder. It’s 687 pages of factory knowledge you can’t find anywhere else. Related manuals: Komatsu 170E-5 Workshop Manual – 685 Pages OEM Factory Specs and Komatsu 170E-5 Workshop Manual – 341 Pages of Factory Specs (note the page count difference – verify which matches your engine), and Komatsu WA65-5 WA70-5 WA80-5 2005 Workshop Manual if you need the loader chassis side. For general manual transmission repair, also see Manual Transmission guides.