Description

Hitachi Sumitomo ZX70-3, ZX70LC-3, ZX70LCN-3, ZX75US-3, ZX85US-3 2008 Workshop Manual

You’ve got a Hitachi Sumitomo excavator in the bay with a leaky swing motor or a pump that’s making noise you don’t like. Without the factory breakdown, you’re guessing bolt sequences and hoping nothing strips. That’s how you turn a two-hour job into a two-day headache. This Workshop Manual is the original Hitachi print—710 pages of the same documentation the dealer techs use. It covers the ZX70-3, ZX70LC-3, ZX70LCN-3, ZX75US-3, and ZX85US-3 models from the 2008 production year. If you need torque values for the swing bearing or the order to crack the main pump, this is where you start.

Tightening Torque Specifications and Torque Chart

Section 1, Group 2 is the first place I flip to on any new machine. The manual includes a complete torque chart for bolts, piping joints, and periodic replacement parts. You get the factory torque spec for every fastener category—not a generic aftermarket table that guesses at grade 8 equivalents. Page references in this section tie directly to the assembly procedures later in the manual, so you’re not cross-referencing three different documents. If you’ve ever had a track adjuster leak because you over-torqued the locknut, you know why this page matters.

Does This Manual Cover the Undercarriage?

Yes. Section 3 is dedicated to the undercarriage: swing bearing removal and installation, travel device disassembly and assembly, center joint service, track adjuster rebuild, front idler and roller maintenance. Each group gives you the removal sequence, inspection limits, and the assembly order with the correct seal orientations. The travel motor brake valve disassembly is on the bookmarks—you’ll find the valve block breakdown and the maintenance standard table. No guessing which shims go where.

3 Critical Systems Covered in This Workshop Manual

First, the pump device: Group 4 in Section 2 walks you through disassembly of main pumps 1, 2, and 3, plus the gear pump structure. Second, the control valve: full disassembly and assembly of the spool bank. Third, the swing device: swing motor and valve block teardown with the maintenance standard. That’s three high-dollar systems that go wrong often. Having the OEM procedure in front of you keeps you from mis-timing the pump pistons or losing a seal in the valve body. For the charge pressure check, you’d reference the Technical Manual for troubleshooting, but the repair steps—torque specs, clearance limits—are here.

Understand the Upperstructure Before You Disassemble

Section 2 covers the cab removal, counterweight, main frame, and all hydraulics above the swing bearing. Group 1 includes dimensions of cab glass if you’re replacing a cracked window. Groups 7 through 10 detail the pilot valves, shut-off solenoid, shockless valve, and solenoid valve unit. Each component has a removal and installation section specific to the ZX70-3 and ZX75US-3 chassis. If you’re working on a ZX85US-3, the manual notes which groups apply to that model—no guesswork about whether the pilot valve differs. The manual’s table of contents is printed on page IN-01, so you can find the exact group without scrolling.

Swing Device: Factory Disassembly Procedure

Group 6 of Section 2 is worth the price of the manual alone. It covers removal and installation of the swing device for both the ZX70-3 and ZX75US-3, then goes into disassembly of the swing motor, assembly of the swing motor, and disassembly and assembly of the valve block. The maintenance standard at the end lists the wear limits for swash plate, cylinder barrel, and valve plate. Without those numbers, you’re measuring against feel—and feel doesn’t hold up at 5,000 PSI. The torque for the motor mounting bolts is in the chart on page [DATA NEEDED], but the manual’s section references make it easy to locate.

Source Validity: Why OEM Beats Aftermarket

This is the genuine Hitachi Sumitomo workshop manual—part number W1P1-E-00, printed in Japan in 2008. It’s not a reprint, not a third-party scan subtracted from a photocopy. The original file runs 710 pages with bookmarks for every group and subgroup. Aftermarket manuals for these machines often combine several model years or skip the maintenance standard tables. You won’t find a piping joint torque or a piston ring gap spec in a generic Chilton-style book. If you’ve ever been burned by a bad torque value that caused a hydraulic leak, you understand the difference. Related manuals for larger Hitachi Sumitomo excavators include the Hitachi Sumitomo SH330 SH330LC 350HD-3B 2006 Workshop Manual – Factory Specs and the Hitachi Sumitomo SCX1500-2, SCX1200-2 Workshop Manual (also available as a Hitachi Sumitomo SCX1500-2, SCX1200-2 Workshop Manual – 506 Pages). For general mechanical background, readers may check external sources on Manual Transmission theory if they’re unfamiliar with hydraulic motor layouts, though the manual itself provides all the service data needed.

Frequently Asked Questions

Does this manual include wiring diagrams?

No. This is the Workshop Manual volume W1P1-E, covering mechanical removal, installation, disassembly, and assembly. The electrical troubleshooting diagrams are in the separate Technical Manual volume TT1P1-E.

What torque values are listed for the swing motor mounting bolts?

The torque chart in Section 1, Group 2 covers all standard bolt grades used in the ZX70-3 series. For the swing motor, you need to refer to the maintenance standard in Group 6 of Section 2, which specifies the tightening torque for the motor-to-bearing bolts. That value is taken from the same chart but is also repeated in the assembly procedure for that motor. The manual’s layout puts the spec right next to the step where you’re torquing the bolts, so you don’t have to flip back and forth. Page references inside each group keep the data consistent across the entire document.

You’re trying to keep a customer’s machine running without buying parts twice. The Hitachi Sumitomo ZX70-3, ZX70LC-3, ZX70LCN-3, ZX75US-3, ZX85US-3 2008 Workshop Manual gives you the factory procedure for every major system. No filler. No third-party guesses. Access the Factory Manual from AutoRepairManuals and get the torque spec you need before you pull the first bolt.