Description

Atlas Copco XA60 Dd, XA70 Dd, XA80 Dd, XA120 Dd, XA160 Dd 1979 Operators Manual

If you have ever cracked open a compressor that someone else “repaired” using aftermarket data, you know the headache. Wrong oil viscosity, safety valve set 10 psi too high, electrical interlocks bypassed. This Atlas Copco XA60 Dd, XA70 Dd, XA80 Dd, XA120 Dd, XA160 Dd 1979 Operators Manual is the original factory book – 36 pages of specs that Atlas Copco built the machines around. You need the charge pressure setting for the XA120 Dd? Page 27 gives the exact relief valve adjustment. You want to understand the Electrical system and safety devices? That section starts on page 10 and covers the stop solenoid linkage, pressure switches, and engine shut-down circuits. Pulling a 1979 XA80 Dd back into service without this book is gambling with your time and your parts budget.

Electrical System and Safety Devices – Page 10

The compressor’s Electrical system interlocks the air receiver pressure with the engine stop solenoid. If the regulating valve fails, the safety switch on page 10 should kill the engine before the pressure relief pops. But you have to know the factory test procedure for those switches – it’s on page 27. I have seen guys reset a tripped switch without checking the downstream unloader valve. That is how you blow a gasket. The manual walks you through the sequence: start the compressor (page 24), let it build pressure, then test each safety device in order. Do not skip that step.

Oil System and Air Receiver Filling – Pages 8-9

The rotary screw compressor relies on a specific oil flow rate. The oil system diagram on page 8 shows the cooler bypass circuit and the filter head orientation. If you install the filter backward – and yes, I have seen that done – you starve the screw element. Page 9 covers the air receiver filling and unloading system. The regulating valve adjustment must match the pressure setting for your rock drill or breaker. Running an XA160 Dd at full load when you only need 80 psi? You are wasting fuel and heating the oil. Set the regulating valve per the manual.

Adjustments: Setting the Compressor Control and Pressure Relief – Page 21

Three adjustments on page 21 that every owner needs to know: compressor control, regulating valve, and pressure relief. The pressure relief valve adjustment is critical – Atlas Copco specifies a deadband test using a gauge tee’d into the receiver line. Do not trust the paint marks on the valve body; they shift with vibration. The manual gives you the open and reseat pressures. For the XA70 Dd and XA80 Dd, those numbers are different from the XA120 Dd and XA160 Dd. Do not mix them up. Page 23 also covers the engine stop solenoid linkage – if the linkage binds, the engine won’t shut down when the safety switch trips. That is a fire risk.

A short paragraph for emphasis: This manual is not a reprint. It is the original 1979 factory PDF, scanned from the actual instruction book.

Maintenance Schedule and Lubrication – Pages 18-20

The practice maintenance schedule on page 18 lists daily, weekly, and 250-hour checks. Oil change intervals depend on the ambient temperature and operating hours – the manual gives a viscosity table for conditions from -20°F to 100°F. Page 20 covers lubrication points, including the air-end oil fill level. Most aftermarket manuals just say “fill to mark.” This one tells you the exact dipstick reading with the compressor level. Overfill the oil separator? You will push oil out the safety valve. Underfill? Screw element failure. Follow the factory schedule.

Audience Fit: Who Needs This Manual?

If you own an Atlas Copco XA60 Dd, XA70 Dd, XA80 Dd, XA120 Dd, or XA160 Dd portable compressor from the 1979 generation, this Operators Manual is the only source for OEM specs. Home garage enthusiasts who rebuild old compressors for farm use – you need the torque values for the oil cooler mounting bolts (page 24) and the safety valve thread size. Professional mechanics running a rental fleet – you need the troubleshooting table on page 32 to diagnose low pressure or high oil temperature without tearing down the air end. Workshop owners who lease these machines to contractors – having this book in your office saves billable hours when a customer claims the compressor is broken and it is just a clogged air filter.

Source Validity: OEM vs. Aftermarket

I will put it plain: aftermarket manuals for 1970s portable compressors are usually copies of copies with missing pages. This one is the genuine Atlas Copco instruction book, supplied with the machine. The cover says “THIS INSTRUCTION BOOK” and the scan includes the original Atlas Copco copyright. The torque specs for the compressor control linkage come from the same engineering department that designed the machines. If an aftermarket manual tells you the safety valve setting for the XA80 Dd is 125 psi, but the factory book says 110 psi, which one do you trust? You trust the guy who built the pump. Page 25 gives the actual relief valve adjustment range. Order the real thing.

Related manuals for similar Atlas Copco models: Atlas Copco XAHS 146 Dd 2006 Operators Manual – Factory Specs, Atlas Copco Boomer L1 D L2 D ML2 D Mark VII 2008 Operators Manual, Atlas Copco XRHS 486 Md, XRHS 396 Md, XRVS 466 Md, XRVS 346 Md 2005 Operators Ma.

Can I use this manual for an XA80 Dd with a different engine than the one shown in the book?

This Operators Manual covers the compressor package, not the engine. Engine-specific service information comes from the engine manufacturer’s manual. For the air end, oil system, and controls – yes, this book applies to any XA80 Dd of that era regardless of engine brand.

Does the manual include torque values for the oil cooler bolts?

Page 24 shows the oil cooler removal and installation steps. It specifies the bolt torque in ft-lbs. If you lose that spec, you risk stripping the mounting threads on the compressor housing – which means a heli-coil repair. Book is 36 pages, and every torque value is OEM.

External resources to cross-check transmission-related info for the compressor drive: Manual Transmission and Manual Transmission (for vehicles that use these compressors).

Access the Factory Manual. 36 pages of OEM data – safety precautions, electrical schematics, adjustment procedures, troubleshooting, and lubrication schedules. If you touch an Atlas Copco XA60 Dd through XA160 Dd from 1979, this is the book that keeps your compressor running and your knuckles intact.