Description

Hitachi Sumitomo ZX800, ZX850H Technical Manual – Factory Assembly Procedures

You are staring at a 75,900 kg machine with 3.4 m³ buckets and wondering where the torque values are for the side frame bolts. That is exactly why you need the Hitachi Sumitomo ZX800, ZX850H Technical Manual in your hands before you touch one fitting. I have been turning wrenches for 28 years, and I have seen more than one shop wreck a superstructure because they guessed the bolt torque or lifted the counterweight wrong. This manual puts an end to that. 209 pages of Hitachi’s own assembly know-how. Not aftermarket junk – this is the OEM document that the factory ships to their own techs.

Safety Precautions and Power Wrench Use

Section 1 starts with safety precautions for servicemen – page 1 shows the cover, but the real meat is in subsections 1-1 through 1-3. They cover how to use a power wrench correctly and general work precautions. If you think you already know how to tighten bolts, read this again. The manual specifies lifting points and part weights so you do not drop a counterweight on your foot. That weight figure on page 3? 73,900 kg for the ZX800 and 75,900 kg for the ZX850H. Respect that number.

Assembly of Superstructure: Side Frames and Counterweight

Chapter 6 walks you through the superstructure assembly step by step. You start with preparation (6-1), then connecting the side frames to the track frame (6-2). Mounting the counterweight (6-3) requires the right bolts and torque – values are listed in the manual. Greasing of swing bearing (6-4) is not optional. After that, releasing air from the main pumps (6-6) and a trial operation (6-7) verify everything works. One missed step here and you are pulling the whole cab again.

Backhoe Front Mounting Procedure

Chapter 7 covers the backhoe front mounting. You get preparation (7-1), actual mounting (7-2), then bleeding the cylinders and checking the hydraulic system (7-3). Adjusting track link tension (7-4) is covered with specific clearance values. The final trial operation check (7-5) and lubrication (7-6) finish the job. If you have the loader front instead, chapter 8 mirrors this with loader-specific specs. Both sections include weights and bucket capacities from the assembly charts.

Appendix: Lifting Diagrams and Lifting Jigs

The appendix (chapter 12) has three subsections: assembly instructions for the right bracket (12-1), left bracket (12-2), and superstructure lifting jig (12-3). These are the drawings you need to fabricate or position jigs so you do not bend anything. A Manual Transmission rebuild might tolerate a few hundred pounds of misalignment – this machine does not. The same applies to Manual Transmission work in smaller gearboxes, but here we are talking about structural steel and 70-ton loads. Use the jig specs.

Audience Fit: Who Needs This Manual

If you are a shop tech assembling these excavators from knockdown kits, this manual is your only source for correct assembly torque, sequence, and special tools. DIY home garage enthusiasts should understand: this is not a routine oil change. The machine weighs as much as a small apartment building. But if you have the equipment and the experience, the manual gives you the exact procedures. Beginners? Do not touch this machine without supervision – but buy the manual anyway and read it through before you even think about starting.

Why OEM Documentation Matters

Aftermarket manuals cut corners. I have seen torque specs that were off by 30% and wiring diagrams that did not match any machine I ever worked on. This Hitachi Sumitomo manual is the original OEM print. The part numbers, bolt torque tables, and hydraulic bleeding procedures come straight from the factory. Page 1 says “Assembly work is the final touch that gives the machine life.” That is not marketing – it is reality. If you want the machine to last, use factory data. For related models, you might also need the Hitachi Sumitomo 330LC, 350H, 350LCH, 370MTH, ZX330 Technical Manual or the Hitachi Sumitomo SH200-3 SH220-3 Technical Manual 166 Pages for smaller excavators. There is also the Hitachi Sumitomo SH240-5 Technical Manual – Factory OEM Specs for medium-sized units. But for the big ZX800 and ZX850H, this is the only manual you need.

Does this manual cover both the ZX800 and ZX850H models?

Yes, it covers both models with separate sections for backhoe front and loader front mounting, including specific weights and bucket capacities for each.

Are torque specifications provided for all critical bolts?

Yes, torque values are listed for all major fasteners in the assembly steps.

What tools are required for assembly?

The manual lists necessary tools and jigs in section 5, including power wrenches, lifting equipment, and specific jigs for superstructure assembly. It also describes how to use a power wrench in section 1-2. The appendix includes lifting diagrams for jigs. Proper tool selection is critical to avoid damage and ensure safety, especially when handling components weighing over 70 tons. You cannot substitute a come-along for the proper lifting jig – the manual shows you exactly what you need.

Can I use this manual for disassembly as well?

This manual is focused on assembly, but the steps can be reversed for disassembly following the same order. Torque values for reassembly are specified, so keep the manual handy when you put it back together.

Do not waste time guessing bolt torque or rigging angles. You have a 75-ton machine to put together. Get the factory data, follow the sequence, and do the job once. Access the Factory Manual and start assembling with the right specs.