TSE DP20-4H, Owner'S Manual

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Overview
This manual includes information on installation, maintenance, and minor repair of these pumps. It
includes a description of the unit and its individual components, troubleshooting information, and minor
repair procedures.
Performing minor repairs may require the unit to be removed 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 Global Service Partners is available for major repairs. Danfoss trains and
certifies Global Service Partners on a regular basis. You can locate your nearest Global Service Partner
using the distributor locator at www.danfoss.com.
Warranty
Performing adjustments and minor repairs according to the procedures in this manual will not affect your
warranty. Major repairs requiring the removal of a unit’s center section, servo sleeves, or front flange
voids the warranty unless a Danfoss Authorized Service Center performs them.
General Instructions
Follow these general procedures when repairing variable displacement pumps.
Remove the unit
If necessary, 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
We recommend you replace all O-rings and seals during service. Lightly lubricate O-rings with clean
petroleum jelly prior to assembly.
Secure the unit
If removed from machine, place the unit in a stable position with the shaft pointing downward. It
will be necessary to secure the pump while removing and torquing fasteners and components.
Service Manual
MP1
Introduction
© Danfoss | July 2017 AX00000244en-US0103 | 5