Charge Check/HPRV
The high pressure relief and charge check valve assembly may be removed for cleaning and replacement
of the O-rings. These valves are factory set and are not field adjustable. Refer to the transmission model
code for the factory setting when ordering replacements.
Removal
1. Using an 24 mm hex wrench, remove the valve seat plugs (N120, P120).
2. Carefully lift the valve (N110, P110) and spring (N100, P100) assemblies from the center section using
a magnet.
Inspection
Inspect the valves and mating seats in the valve seat plugs (N120, P120) for damage or foreign material.
Reassembly
1. Lubricate and install new O-rings (N130, P130) on valve seat plug (N120, P120).
2. Verify that the conical springs (N100, P100) are properly retained on the check relief valves (N110,
P110). Install the valve assemblies into the center section. Ensure each valve assembly moves freely in
its bore.
3. Install the valve seat plugs into the center section and torque to 78.4 N•m [58 lbf•ft].
4. Operate vehicle/machine through full range of controls to ensure proper operation. Check for leaks.
Charge Check/HPRV
P108 167E
78.4 Nm
[58 lbf-ft]
78.4 Nm
[58 lbf-ft]
N120
24 mm
N130
N100
N110
P120
24 mm
P130
P100
P110
Service Manual
LDU20/24 Closed Circuit Axial Piston Transmission
Minor Repair
©
Danfoss | June 2021
AX152886481311en-000304 | 23
