Textron JACOBSEN R-311 69166, Technical/Repair Manual

Page: 271 / 402

6-40 4203781 First Edition
HYDRAULICS
6
Figure 6-35: Right Wing Cutting Unit Pump Test—
Blocking Disk Between Pump and Deck Valve
5. Bypass seat switch and set park brake.
NOTE
Verify engine rpm is within specification (2800 rpm ± 50)
to ensure accurate hydraulic test results.
6. Start engine and run at full throttle (2800 rpm ± 50).
7. Use the flow meter to warm the hydraulic oil. Turn the
flow meter valve until a reading of 1500 psi (103 bar)
or one half of the relief valve rating is reached. Warm
oil to 120–150° F (49–65° C); open valve fully after
operating temperature is reached.
!
CAUTION
8. Enable wing mower deck switch and engage PTO
switch.
9. Slowly close flow meter valve (2) until pressure
reaches 2250 psi (155 bar). Read and record the
right wing cutting unit pump loaded flow.
10. Open flow meter valve (2), disengage switches, and
stop engine.
11. Calculate right wing cutting unit pump leakage.
(Step 13 of previous test – Step 9 / Step 13 of
previous test x 100 = Leak Percentage)
Is right wing cutting unit pump leakage 10% or
less?
YES The right wing cutting unit pump is good.
Proceed to “Right Wing Cutting Unit Deck
Valve Test” on page 6-40.
NO Proceed to next question.
Is right wing cutting unit pump leakage 11% to
20%?
YES The right wing cutting unit pump is marginal.
Additional testing is required. Proceed to
“Right Wing Cutting Unit Deck Valve Test” on
page 6-40.
NO Proceed to next question.
Is right wing cutting unit pump leakage 21% or
more?
YES Repair or replace right wing cutting unit
pump. (See “Gear Pump” on page 6-58.)
Then proceed to “Right Wing Cutting Unit
Deck Valve Test” on page 6-40.
Right Wing Cutting Unit Deck Valve
Test
See Figures 6-36 through 6-38.
!
WARNING
Do not exceed 3350 psi (231 bar) when testing
pump or equipment damage may occur.
TN2251
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 3000 psi (207 bar)
• -10 ORFS Tee Fitting
• -10 ORFS Blocking Disk