Bosch rexroth M1-16 Series Instruction Manual page 49

Table 8: Malfunction table
Malfunction
Neutral circulation
pressure is too high
Movement on consumer
despite neutral position
No detent function
Detent release force is
too high
Troubleshooting | Control blocks for mobile applications
Possible cause
No load-sensing unloading
(applies to M4, M6, M7, SP, SX only)
Control spool not in neutral position
Return flow pressure is too high
Inlet pressure compensator is jammed
Control spool is not in neutral position
Secondary pressure relief valve leaking or
set too low
The control spool leakage is too great
Restoring force in the direction of actuation
is too great compared to the detent force
(spring)
Detent unit is worn
Control spool is jammed
Detent unit is damaged
Detent force is too high
In case of malfunctions caused by contamination, it is essential to check and
possibly improve the quality of the hydraulic fluid through appropriate measures,
such as purging, exchange or additional installation of filters in addition to carrying
out repairs.
Remedy
With tongue: Check the projection,
see "Technical data sheet".
Pressure in the control covers is too high
(check actuation).
Disconnect the return flow from the common return
line; use a separate return line or increase the size of
the line cross section.
Renew the inlet plate.
Pressure in the control covers is too high
(check actuation).
Check the setting pressure on the secondary pressure
relief valve.
Refer to the data sheet for the leakage values
Install a leak-free lowering brake valve.
Remove the detent and clean it.
Renew the detent unit.
See "Not possible to deflect control spool"
under "Control spool is jammed" at the top of this
table.
Renew the detent unit.
Clean the detent unit and grease it. If this is not
successful, renew the detent unit.
RE 64025-B/2021-08-12, Bosch Rexroth AG
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