Textron Jacobsen SLF530, Repair Manual

Page: 232 / 352

6-38 673831-Rev A
HYDRAULICS
6
Figure 6-34
3. Install blocking disk between hydraulic hose (4) and
tee fitting (5).
4. Open flow meter valve (2) completely.
Figure 6-35: Rear Cutting Units Pump Test—
Blocking Disk Between Pump and Rear Reel Valve
5. Block both sides of rear wheels using suitable wheel
blocks.
6. Bypass seat switch.
NOTE
Verify engine rpm is within specification (3000 rpm ± 50)
to ensure accurate hydraulic test results.
7. Start engine and run at full throttle (3000 rpm ± 50).

CAUTION
8 . Use the flow meter to warm the hydraulic oil. Turn the
flow meter valve (2) until a reading of 1100 psi
(75 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.
9. Slowly close flow meter valve (2) until a pressure of
1650 psi (114 bar) or 75% of the relief valve rating is
reached. Read and record the rear cutting units
pump loaded flow.
10. Open flow meter valve, disengage mow switch, and
stop engine.
11. Calculate rear cutting units pump leakage.
(Step 14 of previous test – Step 9 / Step 14 of
previous test x 100 = Leak Percentage)
Is rear cutting units pump leakage 10% or less?
YES The rear cutting units pump is good. Proceed
to step 12.
NO Proceed to next question.
Is rear cutting units pump leakage 11% to 20%?
YES The rear cutting units pump is marginal.
Additional testing is required. Proceed to
step 12.
NO Proceed to next question.
Is rear cutting units pump leakage 21% or more?
YES Repair or replace rear cutting units pump.
See “Gear Pump” on page 6-49, then
proceed to step 12.
NO Proceed to step 12.
12. (See Figures 6-33 and 6-34). Disconnect hydraulic
hose (1) at tee fitting (3) and remove blocking disk.
Reconnect hydraulic hose to tee fitting.
13. Proceed to “Rear Reel Valve Test” on page 6-39.
Do not exceed 2200 psi (251 bar) as this test does
not utilize system relief, and damage may occur
to hydraulic system components.
MAR0161
15
GPM
20
25
30
10
5
0
0
20
40
60
LPM
80
100
3000
psi
BAR
0
1 00
200
30
0
40
0
3600
420
0
48
0
0
5
4 0
0
60
00
24 00
18
00
1 200
6 0
0
0
250
psi
BAR
0
5
1 0
15
20
25
3
0
35
300
350
4 00
4
5
0
50
0
20
0
150
1
00
5
0
0
3
5
6
1
MAR0172