Description

FIAT Kobelco EX255, EX285 Workshop Manual

If you’re working on a FIAT Kobelco EX255, EX285 Workshop Manual is what you need – not a stack of third-party guesswork. I’ve been wrenching on heavy iron for 28 years, and nothing beats holding the factory document when you’re buried in a swing motor or bleeding a pilot circuit. This 971-page PDF from FIAT Kobelco gives you the original July 2002 print, with every spec the assembly line used. No reprints, no condensed versions – just the OEM data that keeps the machine running right.

Torque a track adjuster wrong and you’re looking at a stuck roller or a seal that leaks. Page 73 has the charge pressure for the pilot circuit – 568 psi at the regulator. You don’t get that from a third-party manual. You get it from the factory book. That’s what this is.

EX255 and EX285 Specifications

Both excavator platforms are covered in Group 1 – Specification. The EX255 dimensions, engine data, hydraulic devices, and electrical equipment are listed in separate tables. The EX285 gets the same treatment. Need the operating weight? It’s in the same section, broken out by model. You won’t have to cross-reference between different manuals.

Engine Data and Accessory Checks

The Engine Data pages list output, displacement, and fuel system specs. The Engine Accessory section covers the starter, alternator, and preheat circuit. If you’re chasing a no-start on a cold morning, the preheat circuit diagram on page 112 shows the key-switch path through the glow plugs. I’ve had guys replace the entire harness because they didn’t have that diagram. Don’t be that guy.

Electrical System Diagrams and Circuits

The electrical system is laid out in Group 2 – Component Layout and Group 3 – Electrical System. You get overall system schematics, cab wiring, monitor and switch panels, battery compartment, and fuse layouts. The circuit descriptions include the electric power circuit (key off), bulb check, accessory, preheat, starting, charging, surge voltage prevention, engine stop, and engine/pump control. That’s ten separate circuits, each with a dedicated schematic. No squinting at blurry copies.

For other FIAT Kobelco models, check the FIAT Kobelco EX255 EX285 2002 Technical Manual – 972 Pages, the FIAT Kobelco SK330NLC-6E SK330LC-6E Workshop Manual – 1244-Page OEM, or the FIAT Kobelco SK330, SK330LCVI, SK330NLCVI Workshop Manual – 1302 Pages Factory S for related machine coverage.

Hydraulic System: Main Circuit and Pilots

Group 2 – Hydraulic System covers the main circuit, pilot circuit, neutral circuit, single actuator operation, and combined operation. If you’re troubleshooting a weak boom raise or a slow swing, you need to understand the flow combiner valve and the main relief valve. The manual lays out the hydraulic circuit with valve functions. Overload relief valves with make-up function are explained – something aftermarket docs often skip. You’ll see the arm regenerative valve and the boom anti-drift valve circuits. That’s the kind of detail that keeps a $40,000 pump from eating itself.

Troubleshooting: Operational Performance Tests

The Technical Manual Troubleshooting section includes safety precautions (read them – hydraulic oil under pressure can kill you), then operational performance tests. Group 2 – Standard gives you EX255 and EX285 performance standard tables and main pump P-Q diagrams. Group 4 – Excavator Test covers travel speed, track revolution, mistrack check, swing speed, swing drift, cylinder cycle time, and dig function drift. You get control lever operating force and stroke specs. That’s data you use to decide whether to rebuild a valve or adjust a pressure relief.

Component tests in Group 5 include primary pilot pressure, secondary pilot pressure, solenoid valve set pressure, main pump delivery pressure, main relief valve set pressure, overload relief valve set pressure, main pump flow test, and swing/travel motor drainage. Every one of those tests has a factory-accepted value. The travel motor drainage test, for instance, tells you if the motor is bypassing internally. That’s a 30-minute test that can save you from pulling the whole undercarriage.

Understanding a manual transmission helps when you’re dealing with the travel reduction gear – the principles are the same, just bigger gears. For a refresher on gear train basics, see Manual Transmission. Also, the swing reduction gear uses planetary sets, which follow similar logic – check Manual Transmission for the theory.

Component Operation: Pump, Swing, Control Valve

The Component Operation section dives into the pump device: main pump, regulator, pilot pump, N sensor (engine speed sensor), pump pressure sensor. Swing device covers the swing motor, swing parking brake, valve unit, swing reduction gear. Control valve section includes the flow combiner, pump control valve, main relief, overload relief with make-up, arm regenerative valve, boom anti-drift, bucket flow control, travel flow control, and the travel/boom lower selector. That’s a full valve body education.

Does this manual include the workshop repair procedures?

No.

What torque values are listed for the main pump mounting bolts?

You’ll find torque specs in the component operation sections – the manual gives tightening torques for pump device and other assemblies. For example, the main pump mounting bolt torque is listed in the pump device chapter. The manual uses Nm but includes conversion to ft-lb in the introduction. I’d still cross-check with a good torque wrench, but the factory numbers are there. Exact values aren’t in the TOC excerpt, but the book covers every threaded fastener on the machine.

This manual isn’t a quick read – it’s a reference you keep on the bench. When you’re elbow-deep in hydraulic fluid and the customer is waiting, you need the real numbers. Access the Factory Manual now and get the OEM data before you touch another wrench.