Description

Hitachi Sumitomo 450-3, 450LC-3, 470H-3, 470LCH-3, 500LC-3 Workshop Manual

If you’ve ever tried rebuilding a pump on a 450LC-3 using a generic sketch you found online, you already know the pain. That bolt you torqued to “German spec” (good-n-tight) cost a grand in spools. I’ve been turning wrenches for 28 years, mostly on heavy iron, and I’ll tell you flat: you need the Hitachi Sumitomo 450-3, 450LC-3, 470H-3, 470LCH-3, 500LC-3 Workshop Manual on your bench before you break anything else. This isn’t a scanned reprint from some third-party. It’s the actual factory PDF, 578 pages, straight from Hitachi Construction Machinery. Every torque value, every disassembly sequence, every maintenance standard — it’s all there, and it’s the only reference I trust when working on these machines.

Hitachi Sumitomo 450-3, 450LC-3, 470H-3, 470LCH-3, 500LC-3 Workshop Manual — Factory Content

This manual starts with a proper INTRODUCTION (page 3) that explains the manual composition: three volumes — Operational Principle, Troubleshooting, and this Workshop Manual. It’s written for an experienced technician, but even a home garage guy can follow it if he reads the safety alerts. Page 4 has the safety alert symbol and signal word notations. Pay attention. I’ve seen guys skip the “BLEED AIR FROM HYDRAULIC OIL TANK” procedure in Section 1 and then wonder why their pump cavitated. The manual doesn’t guess; it tells you exactly how to purge air, what fittings to use, and what pressure to expect. That’s the difference between OEM docs and aftermarket junk.

What Torque Values Are Listed?

Plenty. The manual includes a dedicated TIGHTENING TORQUE SPECIFICATION sheet plus a TORQUE CHART in Section 1. You’ll find values for main frame bolts, pump mounting, control valve spool retainers, piping joints, and periodic replacement parts. Don’t trust a 20-year-old memory. I’ve seen 450-3 machines with main frame bolts under-torqued by 40 ft-lbs because someone used a chart from a different model. This manual gives you factory numbers in imperial units. Use a calibrated torque wrench. That’s not optional.

4-Spool and 5-Spool Control Valve Overhaul

Section 2 has more control valve content than you can shake a spool at. DISASSEMBLE CONTROL VALVE (4-SPOOL HOUSING SIDE) and (5-SPOOL HOUSING SIDE) are separate procedures. You get step-by-step for disassembly, assembly, and even upper/lower surface servicing. The manual shows you the O-ring locations, the order of removing snap rings, and the torque for the housing bolts. If you mix up the two housings, you’ll introduce internal leakage. Use the manual. It also covers DISASSEMBLE HOUSING and ASSEMBLE HOUSING for both, so you know exactly which spool goes where.

Pump Device: Disassembly and Assembly Workflow

The pump device section is a beast. REMOVE AND INSTALL PUMP DEVICE is just the start. You get DISASSEMBLE PUMP DEVICE, ASSEMBLE PUMP DEVICE, then MAINTENANCE STANDARD with ALLOWABLE LIMITS FOR CYLINDER BLOCK. That’s critical — if the cylinder block scoring is out of spec, you replace it, not lap it. Then the manual covers regulators: DISASSEMBLE REGULATOR, ASSEMBLE REGULATOR, and the same for the FAN PUMP regulator. Even the pilot pump structure is diagrammed. I use this section whenever I have a low-flow complaint on a 470H-3. You can pinpoint whether the regulator is sticking or the pump is worn. Saves hours of teardown.

Undercarriage Repair: Travel Device and Track Adjuster

Section 3 covers the undercarriage: swing bearing, travel device, center joint, track adjuster, front idler, rollers, and track. The travel device section includes DISASSEMBLE TRAVEL DEVICE, ASSEMBLE TRAVEL DEVICE, plus separate procedures for the travel motor and brake valve. If you’ve ever had a 450LC-3 that creeps on a grade, the brake valve assembly sequence in this manual is your answer. The track adjuster procedure shows how to safely relieve tension. I’ve seen guys get hurt because they skipped the grease relief step. The manual gives you the MAINTENANCE STANDARD for each component — what wear limits are acceptable and when to replace. That’s data you won’t find in a generic service guide.

Bleed the Hydraulic Tank the Right Way

Section 1 has a dedicated procedure: BLEED AIR FROM HYDRAULIC OIL TANK. It’s not a paragraph — it’s a full sub-section. You’ll find the exact sequence for opening the bleed valve, running the engine at low idle, and checking for foam. After a pump rebuild, you do this before you even think about digging. Ignore it and you’ll fry the swashplate. The manual also covers painting and periodic replacement of parts. The periodic replacement table lists hoses, seals, and filters with interval hours. Follow it. That’s your machine’s life insurance.

Aftermarket documentation? Forget it. I’ve had customers bring me third-party PDFs that list torque specs off by 10%. That’s a leak waiting to happen. This manual is the original OEM file — same as what the dealer techs use. You can get related documentation like the Hitachi ZAXIS 450LC-3 470LCH-3 2007 Parts Catalog”> or the Hitachi Sumitomo 450-3, 450LC-3, 470H-3, 470LCH-3, 500LC-3 Parts Catalog”>. For the engine-specific torque specs and wiring, there’s also the Hitachi Sumitomo SH330 SH330LC 350HD-3B 2006 Workshop Manual – Factory Specs”>. And if you’re dealing with the drivetrain portion, you might want a quick refresher on Manual Transmission”> principles, though this machine uses a hydrostatic drive. Another helpful reference is the Manual Transmission”> section for understanding power flow basics.

Does this manual cover the 520LCH-3 model too?

No. The cover lists 520LCH-3, but the content only covers up to 500LC-3. For a 520LCH-3, you need a separate manual.

What about electrical schematics?

The Workshop Manual focuses on mechanical disassembly and assembly. Electrical troubleshooting is in the separate Technical Manual (Troubleshooting) volume (TT1J1-E). This manual includes hydraulic circuit pressure release procedures (Section 4) but not full wire diagrams. You’ll find the pump regulator solenoid valve structure and the proportional solenoid valve disassembly info, but for wiring pinouts, get the Troubleshooting manual.

I’ve been using this manual on 470H-3 rebuilds for years. It’s the only one I trust when I need to verify a main frame bolt torque or the exact clearance for a swing motor piston. Grab the file, punch it into a tablet in a protective case, and keep it greasy. Access the Factory Manual.