Jacobsen AR3, Техническое руководство по ремонту

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6-30 4181384 First Edition
HYDRAULICS
6
The results from this test reveal leakage of 5% in the
traction pump, 5.3% in the mow/brake valve, 20% in the
left cutting unit motor, 5.6% in the right cutting unit motor,
and 4.4% in the center rear cutting unit motor. Although
all the components lend to the overall system leakage,
only the left cutting unit motor, which is at the extreme
end of the marginal range, would be considered for
repair/replacement.
Formulas:
Cutting Unit Motor and Mow/Brake Valve
Loaded Flow from previous component - Loaded Flow
from current component / Loaded Flow from previous
component x 100 = Leak Percentage
System and Cutting Unit/Charge Pump
No Load Flow - Loaded Flow / No Load Flow x 100 =
Leak Percentage
Calculations:
System Test
No Load Flow = 10 gpm
Loaded Flow = 6.5 gpm
10 - 6.5 / 10 x 100 = Total System Leakage 35%
Cutting Unit/Charge Pump Test
No Load Flow = 10 gpm
Loaded Flow = 9.5 gpm
10 - 9.5 / 10 x 100 = Traction Pump Leakage 5%
Mow/Brake Valve Test
Loaded Flow from cutting unit/charge pump test = 9.5
gpm
Loaded Flow from mow/brake valve test = 9 gpm
10 – 9 / 9.5 x 100 = Mow/Brake Valve Leakage 5%
Left Cutting Unit Motor Test
Loaded Flow from mow/brake valve test = 9 gpm
Loaded Flow from left cutting unit motor test = 7.2 gpm
9 – 7.2 / 9 x 100 = Left Cutting Unit Motor Leakage 20%
Right Cutting Unit Motor Test
Loaded Flow from left cutting unit motor test = 7.2 gpm
Loaded Flow from right cutting unit motor test = 6.8 gpm
7.2 - 6.8 / 7.2 x 100 = Right Cutting Unit Motor Leakage
5.0%
Center Rear Cutting Unit Motor Test
Loaded Flow from right cutting unit motor test = 6.8 gpm
Loaded Flow from center rear cutting unit motor test =
6.5 gpm
6.8 – 6.5 / 6.8 x 100 = Center Rear Cutting Unit Motor
Leakage = 4.4%
Cutting Unit/Charge Pump System
Test
See Figures 6-19 and 6-20.
!
WARNING
1. Park the mower safely. (See “Park Mower Safely” on
page 1-7.)
2. Raise seat platform.
3. Bypass seat switch.
Figure 6-19
4. Disconnect hose (1) from fitting (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
• Test Hose 3000 psi (207 bar)
• Tee Fitting
• Blocking Disk
TN1124
1
2