Description

O&K RH6 1972 Operators Manual – The Factory Procedure for Your Crawler Excavator

Not having the factory manual for a 1972 O&K RH6 means you are guessing on control layouts, safety procedures, and maintenance intervals. I have seen too many guys burn up a hydraulic pump because they turned the wrong valve or skipped a grease point. This O&K RH6 1972 Operators Manual gives you the original 60 pages of operating instructions straight from Orenstein & Koppel. No aftermarket rewrite. No missing sections. Just the factory document that the dealer handed over with the machine.

Operating Instructions for the RH6 Crawler Excavator

You get the full sequence for starting and stopping the engine, working the shovel arm, slewing the upper carriage, and traveling on slopes. Page 12 covers the starting procedure – including the pilot start sequence that keeps the safety lock engaged. Page 14 shows the arrangement of control units. If you have ever tried to figure out which lever does what on an unfamiliar machine, you know why this page alone is worth the access. The manual also tells you how to handle the machine on roads per road transport regulations. That is something aftermarket pamphlets often skip.

Contents: From Accident Prevention to Wiring Diagrams

Look at the table of contents. It starts with accident prevention (page 8) and goes through hints for arduous applications, appropriate blasting, and then the handling and maintenance sections. The wiring diagram is on page 53. The hydraulic system diagram is on page 55. There is a lubrication chart on page 57 with instructions running through page 61. Every section is numbered and cross-referenced. You can jump straight to the track tensioning procedure on page 41 or the sliding ring seal replacement on page 44 without flipping through unrelated material.

Accident Prevention and Safety Procedures (Page 8)

Every operator should read page 8 before they even turn the key. The factory lays out safe operating conditions, required personal protective equipment, and what to do when working near power lines. That page alone can keep you out of the hospital. A reprinted copy or a PDF with missing pages leaves you exposed. This manual has the complete original layout.

How to Use the Hydraulic System Diagram

The hydraulic system diagram on page 55 is not a generic schematic. It shows the exact routing for the RH6 – pump, control valves, cylinders, and filters. When you are troubleshooting a drift in the boom or a sluggish slewing gear, you trace the lines on that diagram and find the check valve that is stuck. I have used it to locate a bad seal in the travel motor. You cannot get that level of specific information from a third-party wiring book. Related: check out O&K RH90-E 1998 Electrical Schematic – Factory Wiring Manual”> for a newer machine, but for the RH6 this is the one.

3 Critical Maintenance Sections You Need

First, the engine oil level and change schedule on page 23. Second, the hydraulic oil filter replacement on page 36 – including the type of oil (page 39) and the proper change interval. Third, the track tensioning procedure on page 41. If you run the tracks too loose, the sprocket jumps. Too tight, you break the rollers. The factory spec says exactly how much sag to allow. That is the difference between a machine that lasts ten thousand hours and one that gets scrapped at five thousand. Also see O & K Trojan L2000 Parts Catalog – OEM Factory 131-Page Manual”> and O&K Trojan 1900Z 1990 Parts Catalog – Factory OEM 363-Page Manual”> if you need parts breakdowns for other O&K models.

OEM vs Aftermarket: Why This Manual Is Different

Aftermarket manuals often copy the general theory of operation but leave out the machine-specific details. For example, the RH6 uses a Loctite sealant on certain piping connections (page 27). The factory notes exactly which thread locker to use and how to apply it. A generic manual will say “apply thread sealant” without the specification. Also, the wiring diagram on page 53 is drawn with the actual pin numbers and wire colors from the 1972 production run. If you need to understand how the manual transmission of the travel gear works, see the separate Manual Transmission”> guide, but for the RH6 electrical and hydraulic systems, this is the only source. Another Manual Transmission”> resource covers a different drivetrain, but again, stick with factory when you can.

Audience Fit: Who Needs This Manual?

If you are a home garage enthusiast restoring an old RH6, you need the lubricant specifications and the correct procedure for retensioning tracks. If you run a small excavation company and just bought a used RH6, you need the daily operating checks and the winter operation tips (page 24). Even a seasoned mechanic like me pulls out the factory manual before adjusting the slewing brake (page 32) because the clearance spec is not something you remember off the top of your head. Beginners: do not attempt any hydraulic system work without first reading the safety warnings and the system diagram. This manual is written for operators who already know how to turn a wrench but need the factory numbers.

Frequently Asked Questions

Does this manual cover the RH6 loader configuration?

Yes, the manual covers both excavator and loader configurations. The table of contents lists sections for the shovel arm operation, bucket emptying, and a specific procedure on page 78 for “Changing the attachments (from loading shovel to clamshell)”. That means if you have a machine that switches between a digging bucket and a clamshell, the factory steps are documented. You also get the hydraulic system diagram that applies to both setups. Additionally, the “Working Attachments” section on page 40 and the jib maintenance instructions are common to both. So anyone running an RH6 in either role gets the complete operating procedures from the OEM.

Is the wiring diagram accurate for North American models?

The wiring diagram on page 53 is for the European export model. If your machine has been retrofitted with different electrical components, verify against your actual harness. The diagram is still useful for tracing the original layout and understanding the relay logic.

What languages is this manual in?

English.

How many pages?

60 pages.

Stop guessing with your RH6. Access the Factory Manual and keep your excavator running right.