Bosch Rexroth Hagglunds VI 44 Series Installation And Maintenance Manual page 61

Hydraulic motor with 2-speed valve V46-C
Fault
The motor only works
at one speed
Motor cannot be run
in single or double
speed (2-speed valve
or three position type)
Hydraulic motor with counterbalance valve V46-O
Fault
The motor only rotates
in one direction
The motor does not
supply any back pressure.
Hydraulic motor with band brake
Fault
Insufficient braking
torque
The motor runs
sluggishly when idling
The brake does not open
The brake cylinder
leaks oil
Probable cause
2-speed plug not fitted
2-speed valve of two position
type fitted – pilot pressure
too low.
The valve piston has stuck in
single-speed position due to
impurities in the oil.
Pilot pressure too low.
The valve piston has stuck in
0-position due to impurities.
Probable cause
The valve piston has stuck
in unloaded position.
The valve piston has stuck
in fully open position.
Probable cause
The brake is poorly adjusted.
The brake cylinder is not
drained in the described
manner, excessive counter
pressure in drainage line.
The brake band and the brake
surface are dirty or greasy.
The brake is excessively
tensioned. The brake band
is applied despite the brake
opening.
Insufficient brake opening
pressure.
Seals or piston damage.
Hägglunds VI, RE 15310-WA/10.2015, Intallation and maintenance manual, Bosch Rexroth Mellansel AB
Action
Fit 2-speed plug in the bottom of connection "A" in the motor.
Suitable pilot pressure – see 3.2.5 for valve V46-C.
Dismount piston and remove impurities.
Required pilot pressure: See 3.2.5 for valve V46-C
Dismount the piston and remove impurities.
Action
Dismount the piston and remove any impurities.
Dismount the piston and remove any impurities.
Action
Adjust the brake. See the instruction for brake adjustment under 3.1.5
"Motor – front bracket".
Remove the cause of the pressure. Concerning the maximum counter
pressure, see the section dealing with draining the brake cylinder under
3.1.5 "Motor – front bracket".
Dismantle the brake band and sandpaper the surface of the lining.
Clean the brake surface on the motor, If necessary, replace the
complete brake band.
Relieve the tension. See section dealing with draining the brake cylinder
under 3.1.5 "Motor – front bracket".
For the required opening pressure, see section dealing with draining
the brake cylinder under 3.1.5 "Motor – front bracket".
Replace the seals / replace the pistons.
IMPORTANT / CAUTION!
The spring in the brake cylinder is tensioned.
Fault finding 61/68