Nilfisk-Advance 7765 Service Manual page 57

Service Manual – Advance 7765 / Nilfisk CR1500
Scrub Deck Cylinder
The
Scrub Brush Solenoid (6)
control valve control the scrub deck hydraulic cylinder to lower and raise the scrub deck, and determine
which of the two scrub pressures is used. The
and raise the scrub deck.
• Scrub Deck Down at Normal Scrub Pressure
When the
Ignition Switch
on the scrub deck cylinder with the hydraulic return line to the reservoir. The equal pressure on both
ends of the scrub deck cylinder allows the scrub deck to lower to the floor under its own weight.
• Scrub Deck Down at High Scrub Pressure
When the
Drive Pedal Forward Sensor
the
Scrub Brush Switch
("two-bar") position, the
connects the top port on the scrub deck cylinder to the 270 psi oil from the power steering unit. This
presses the scrub deck downward to its heavy scrub pressure setting. Note that the
will light when in the heavy scrub ("two-bar") position.
• Scrub Deck Up
When the
Drive Pedal Forward Sensor
the
Scrub Brush Solenoid (6)
connects the bottom port on the scrub deck cylinder to the 270 psi oil from the power steering unit to lift
the scrub deck upward to its retracted position.
Also refer to the
Scrub System Hydraulic Diagrams
,
Scrub Brush Solenoid (8)
Ignition Switch
is on, the
Scrub Brush Lock Up Solenoid (9)
switches the
is set to the position and the
Lower
Scrub Brush Lock Up Solenoid (9)
switches the
will be energized and the
and
Scrub Brush Lock Up Solenoid (9)
must be on for the scrub deck cylinder to lower
is energized. This connects both ports
contacts to the
Forward Relay R4
Brush Pressure Switch
and
Scrub Brush Solenoid (8)
contacts to the
Forward Relay R4
Scrub Brush Solenoid (8)
section.
Scrub System
in the cylinder
( ) position,
87 Lower
is set to the heavy scrub
are energized. This
Brush Pressure Switch
( ) position,
87a Raise
will be de-energized. This
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