Description

Fiat-hitachi EX100WD Parts Catalog – OEM Factory Documentation

If you’re wrenching on an Fiat-hitachi EX100WD, you know the frustration of chasing part numbers that don’t match the machine. This Parts Catalog is the factory-issued document—251 pages of original Japanese and English text—that lists every component by serial number range. No third-party cross-references, no ‘use this instead’ nonsense. You get the exact OEM number for every Valve, every Cylinder, every seal, and every hydraulic line. I’ve seen guys burn a full day on a single O-ring because they used an online interchange. This stops that.

This document comes straight from Hitachi’s own parts system. The table of contents is laid out exactly as the engineers intended: PUMP, MOTOR ; OIL, VALVE, CYLINDER, POWER TRAIN, ETC., and a PARTS INDEX. Each section gives you exploded diagrams with callout numbers, factory part numbers, quantities per assembly, and service codes like W (field modification needed), D (replace as assembly), K (kit part), R (adjustment shim quantity varies), S (service-only part), OP (optional), OS/US (oversize/undersize). That kind of detail saves you from ordering a part that won’t fit because of a serial break you didn’t know existed.

PUMP Section: What’s Inside the Hydraulic Pump Group

Look at the PUMP chapter first if you’ve got a whine or low pressure. It covers the main hydraulic pump assembly, including the gear pump for pilot control. Each internal part—pistons, swash plate, valve plate—has its own number. The service code column tells you whether you can buy the piston alone (W code means you’ll need to machine the bore locally) or if you have to buy the whole rotating group (D code). I’ve rebuilt these pumps on an EX100WD before; having the OEM diagram side-by-side with the actual parts saves about an hour per assembly.

MOTOR; OIL Section: Hydraulic Motor and Oil System Details

Travel and swing motors live in the MOTOR ; OIL section. This isn’t just a list of part numbers—it includes the oil cooler, filter head, and all the hoses in between. The ‘Oil’ sub-section covers the charge pump and lubrication circuit. If you’re chasing a motor seal leak, you’ll find the exact shaft seal part number here, not a generic cross. The manual even tells you if the motor is serial-number-dependent (look for the ‘H’ prefix in the application column, which refers to the motor’s own manufacturing number stamped on the housing).

VALVE Section: Valve Assemblies and Service Codes

Every control valve—main spool, relief, check, pilot—is in the VALVE chapter. The exploded view shows proper orientation of springs and poppets. Service codes like ‘P’ (part is superseded, use the alternative shown) or ‘Y’ (full interchangeability) keep you from installing a valve that’s been obsoleted. I’ve watched mechanics stack shims wrong because they relied on memory. This manual shows the exact stack height per serial range. When you’re ordering a relief valve cartridge, you need the code stamped on the valve body; the Parts Catalog maps that code to the right part number.

CYLINDER Section: Cylinder Parts and Interchangeability

The CYLINDER chapter covers all hydraulic cylinders—boom, arm, bucket, and stabilizer. Each seal kit is listed with both the part number and the quantity of each seal ring. The compatibility column (I, P, T, Y) tells you if a newer seal kit can replace an older one without changing the gland. On an older EX100WD, you’ll often find that a cylinder from a later serial number uses a different piston seal. The manual flags that with a ‘T’ code, meaning you need to replace the piston and seal together. That saves you a come-apart job.

POWER TRAIN Section: Powertrain Components and Ordering

POWER TRAIN includes the transmission, axles, differentials, and final drives. Each gear, bearing, and seal has its own line. The parts index at the back lists every number alphabetically by part code, so if you’ve got a bearing number from a worn-out part, you can find its location in the book. This section also includes the axle housing assemblies and wheel brake parts. For the EX100WD, the front axle drive and rear axle are different; the manual separates them clearly by serial prefix.

ETC. Section: Additional Systems Covered

Don’t skip the ETC. chapter. It covers everything that doesn’t fit neatly into the big four subsystems: cab components, electrical box, hydraulic tank, and mounting hardware. You’ll find the part numbers for the ROPS cab glass, wiper motor, and control lever handles. The ‘Remarks’ column sometimes references service bulletins—e.g., a bolt torque update. That’s factory data you can’t get from a third-party site. If you’re restoring a machine, this chapter saves you from hunting for obsolete interior parts.

PARTS INDEX: How to Find Part Numbers Fast

At the end of the 251-page document, the PARTS INDEX lists every part number in numeric/alphanumeric sequence. Each entry points to the page and callout number where the part appears. Need the part number for the main pump drive shaft? Scan the index, note the page, flip to the PUMP exploded view. No guesswork. The index also marks new parts with an asterisk (*) so you can see if a part was added in a revision. That’s especially helpful when dealing with serial breaks that occurred mid-production.

Source Authenticity: Why an OEM Parts Catalog Beats Aftermarket Cross-References

I’ve been down the aftermarket road. Their catalogs are often scanned from a worn-out copy, missing pages, or they substitute a ‘universal’ number that doesn’t match the thread pitch. This PDF is a direct digital copy of the original Hitachi publication. The Japanese and English text is intact, the drawings are crisp, and the service codes are legible. You can zoom in on the seal sizes. Compare that to an online parts lookup where you’re typing in a model and hoping the website’s database has been updated. This manual has the machine serial range right on the cover: applicable serial number 0103~. That’s your starting point.

If you work on other models, check out the Fiat-hitachi 850-3, 850LC-3, 870H-3, 870LCH-3 Parts Catalog for similar OEM coverage. For smaller excavators, the Fiat-hitachi ZX50U-2 Parts Catalog – 120 Pages of OEM Specs is also available. For context on why OEM documentation is the industry standard, see the Automotive Industry Overview. And since we’re dealing with heavy equipment, the Automotive Industry Overview gives background on manufacturing standards that apply to hydraulic component sourcing.

Does this Parts Catalog include torque specs for bolts?

No. This is a parts catalog, not a service manual. It focuses on part numbers, quantities, and ordering info. For torque values, get the appropriate service manual. The catalog does, however, list service codes that sometimes hint at torque requirements (e.g., a ‘W’ code might mean field adjustment of a locknut).

Can I use this to rebuild the hydraulic cylinders on my EX100WD?

Yes, the CYLINDER section gives you all seal kit part numbers and indicates if a piston or rod needs replacement. The exploded view shows the order of seals, wipers, and backup rings. But for disassembly and reassembly procedures, you need the workshop manual.

How do I interpret the compatibility codes I, P, T, Y?

I means the listed part can be replaced by the alternative, but not the reverse. P means the original part is prohibited; use the alternative. T means you must use the alternative as a set (e.g., a piston and seal together). Y means full bidirectional interchange. The catalog explains this on page 4 (the foreword).

Is this the same Parts Catalog that Hitachi dealers use?

Yes, this is the identical publication with the same part number (PIIB-EI-4) and serial number coverage. Dealers use this exact document to order parts for your machine. The only difference is you get it as a digital PDF instead of a binder.

Order your copy of the Fiat-hitachi EX100WD Parts Catalog and stop wasting time on wrong parts. Every number you need is inside these 251 pages. Access the Factory Manual now and keep it on your shop tablet or print the sections you need. Your machine will thank you.