HYDRAULICS
4203781 First Edition 6-33
6
Adjust Front Cutting Unit Deck Valve
System Relief Valve Pressure
See Figure 6-25.
!
WARNING
NOTE
This adjustment should be done in conjunction with front
cutting unit deck valve test.
1. Park the mower safely. (See “Park Mower Safely” on
page 1-6.)
2. Perform front cutting unit deck valve test. (See “Front
Cutting Unit Deck Valve Test” on page 6-31.)
Figure 6-25
3. Loosen nut (1).
4. Rotate screw (2) to adjust the relief valve pressure
setting.
To increase the pressure setting: Turn the screw
in (clockwise).
To decrease the pressure setting: Turn the screw
out (counterclockwise).
5. Tighten nut (1).
Could relief valve be adjusted to 2700–3300 psi
(186–228 bar)?
YES Front cutting unit deck valve system relief
valve is good. Proceed to “Front Cutting Unit
Motors Test” on page 6-33.
NO Repair or replace front cutting unit deck valve
system relief valve. (See “Front Deck Valve”
on page 6-65.)
Front Cutting Unit Motors Test
See Figures 6-26 through 6-29.
IMPORTANT
• This test works together with the front cutting
units circuit test to isolate a problem with the
front cutting units circuit.
• Performing this test will isolate the front cutting
unit motors from the rest of the front cutting unit
circuit.
!
WARNING
1. Park the mower safely. (See “Park Mower Safely” on
page 1-6.)
2. Before performing this test, perform front cutting unit
deck valve test, leaving flow meter connected as
outlined.
3. Bypass seat switch and set park brake.
The hydraulic system is under pressure, and the
oil will be hot.
• Always relieve pressure in the hydraulic
system before performing service.
• Failure to follow appropriate safety
precautions may result in death or serious
injury.
Required Tools and Materials
• Flow Meter
• -10 ORFS Test Hose 3600 psi (248 bar)
• -10 ORFS Tee Fitting
• -10 ORFS Blocking Disk
1
TN2301
2
The hydraulic system is under pressure, and the
oil will be hot.
• Always relieve pressure in the hydraulic
system before performing service.
• Failure to follow appropriate safety
precautions may result in death or serious
injury.
Required Tools and Materials
• Flow Meter
• -10 ORFS Test Hose 3600 psi (248 bar)
• -10 ORFS Tee Fitting
• Blocking Device or Tool