Overview; Warranty; General Instructions; July - Danfoss Series 42 Service Manual

Service Manual
Introduction

Overview

Warranty

General instructions

Series 42 Axial Piston Closed Circuit Pumps
This manual includes information for the installation, maintenance, and minor repair of Series 42 axial
piston closed circuit pumps. It includes a description of the unit and its individual components,
troubleshooting information, and minor repair procedures.
Performing minor repairs requires you to remove the unit from the vehicle/machine. Thoroughly clean
the unit before beginning maintenance, or repair activities. Since dirt and contamination are the greatest
enemies of any type of hydraulic equipment, follow cleanliness requirements strictly. This is especially
important when changing the system filter and when removing hoses or plumbing.
A worldwide network of Danfoss Authorized Service Centers (ASCs) is available for major repairs. Danfoss
trains and certifies ASCs on a regular basis. You can locate your nearest ASC using the distributor locator
at www.sauer-danfoss.com. Click on the Sales and Service link.
Performing installation, maintenance, and minor repairs according to the procedures in this manual does
not affect your warranty. Major repairs requiring the removal of a unit's rear cover or front flange voids
the warranty unless done by a Danfoss global service partner.
Follow these general procedures when repairing Series 42 variable displacement closed circuit pumps.
Remove the unit
Prior to performing minor repairs, remove the unit from the vehicle/machine. Chock the wheels on the
vehicle or lock the mechanism to inhibit movement. Be aware that hydraulic fluid may be under high
pressure and/or hot. Inspect the outside of the pump and fittings for damage. Cap hoses after removal to
prevent contamination.
Keep it clean
Cleanliness is a primary means of assuring satisfactory pump life, on either new or repaired units. Clean
the outside of the pump thoroughly before disassembly. Take care to avoid contamination of the system
ports. Cleaning parts with a clean solvent wash and air drying is usually adequate.
As with any precision equipment, you must keep all parts free of foreign material and chemicals. Protect
all exposed sealing surfaces and open cavities from damage and foreign material. If left unattended,
cover the pump with a protective layer of plastic.
Replace all O-rings and gaskets
Danfoss recommends replacing all O-rings, gaskets, and seals when servicing. Lightly lubricate all O-rings
with clean petroleum jelly prior to assembly.
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