Gravely 989003, Руководство по обслуживанию

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3. Connect the lift control linkage to the valve spool.
4. Refer to Servicing The Hydraulic System and
Priming the Transmission if hydraulic system
bleeding is needed.
5. Start the unit and operate the valve. Ensure that
the spool is traveling its full stroke in both
directions for proper operation of the valve.
8.6 HYDRAULIC VALVE ADJUSTMENT
1. With the unit shutdown, install a pressure gauge
into one of the high pressure hydraulic hoses
between the hydraulic valve and lift cylinder. Refer
to the hydraulic diagram, Figure 16.
2. The pressure should read between 800 to 1000
psi, when the lift lever is held in the raised position
with the unit running at full throttle. The maximum
pressure on the lift system should not exceed 1000
psi.
3. If the pressure needs to be adjusted remove the
acorn nut on the valve body. Loosen the jam nut
while holding the adjusting screw with a
screwdriver.
4. With the unit running at full throttle, rotate the
adjusting screw clockwise to increase the hydraulic
pressure or counterclockwise to decrease the
hydraulic pressure.
5. Shutdown the unit once the recommended
pressure is consistently maintained. Hold the
adjusting screw and tighten the jam nut and install
the acorn nut.
8.7 HYDRAULIC LIFT CYLINDER
REMOVAL
1. Disconnect the two hydraulic hoses from the
hydraulic cylinder and cap.
2. Remove the cotter key and clevis pin at the deck
lift weldment.
3. Remove the cotter key and clevis pin at the tractor
frame.
4. Repair or replace any worn or damaged parts.
8.8 HYDRAULIC LIFT CYLINDER
INSTALLATION
1. Install the hydraulic cylinder with the ram towards
the attachment with the two clevis pins and cotter
keys.
2. Connect the two hydraulic hoses to the lift cylinder.
3. After any hydraulic hose maintenance system
servicing, refer to Hydraulic System Servicing and
Hydraulic System Bleeding.
CAUTION: Prior to working on the hydraulic
valve, move the lift lever to the float position to
release any hydraulic fluid pressure in the
hydraulic system.
CAUTION: Prior to working on the hydraulic
valve, move the lift lever to the float position to
release any hydraulic fluid pressure in the
hydraulic system.