Grove toucan 1010, Service Manual

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21
Models
Revision 02-2000
Toucan 1010
Relief valves used in the work platform's hydraulic
system protect the system from excessive pressure
(within the circuit in which they are used) by returning
hydraulic oil to the hydraulic reservoir when the
pressure setting is exceeded.
You can determine the point at which a relief valve
opens by placing a pressure gauge in the pressure
test port of the appropriate valve manifold. The needle
on the pressure gauge will climb until it reaches the
relief valve setting. At that point, the needle will stop
climbing and fluctuate - indicating that the relief valve
is open and returning hydraulic oil to the hydraulic
reservoir.
Correct relief valve adjustment is mandatory if any
hydraulic circuit is to function properly. Relief
pressure settings must always be within established
tolerances.
NOTE
Adjustment of relief valve pressure settings
should only be performed - after the need for
adjustment has been established - by qualified
mechanics using the correct equipment.
NOTE
Check pressure settings prior to delivery of
work platform.
The table titled Relief Valve Pressure Settings lists
main and circuit relief valve pressure settings. If the
pressure setting of any relief valve is not ± 5 bar of
the setting listed in the table, adjust valve as
necessary (unless otherwise specified).
Do not overtighten the adjustment screw or
locknut.
Do not hold the relief valve open for more
than one minute.
For a correct relief valve pressure check, the
locknut of the relief valve adjustment screw
must be tightened.
NOTE
To adjust a relief valve turn the adjustment
screw (in to increase or out to decrease) until
the proper setting is reached.
! CAUTION
! CAUTION
! CAUTION
3.1 Relief valve setting
NOTE
Check the relief valve adjustments with a
pressure gauge connected to the pressure
test port (M) of the FUNCTION MANIFOLD
except for the brake release relief valve [PR7].
Check brake release relief valve [PR7]
adjustment with a pressure gauge connected
to the pressure test port (M) of the BRAKE
MANIFOLD.
Preparation
NOTE
Before setting pressures, warm the hydraulic
oil to between 25°C to 50°C.
NOTE
Use a 0 to 40,0 MPa/400 bar pressure gauge
when adjusting the relief valves. For
pressures lower than 3 MPa/30 bar, use a 6
MPa/60 bar pressure gauge.
NOTE
When adjusting the relief valves, operate the
machine from the platform controls AT
MAXIMUM SPEED.
Brake manifold
Function manifold
Test plug
PR8
PR7
ä
PR1
PR2
PR6
PR5
PR4
PR3
Test plug
ä
PRESSURE SETTINGS 3 3