Cushman TURF-TRUCKSTER, Service & Repair Manual

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PUMP FLOW TEST SECTION 2 (See Figure 8J-12)
1. At the pump, remove the outlet line from pump
section 1. Plug line.
2. Install a tee to pump outlet port.
3. Connector flowmeter “IN” port line to the pump
tee. Cap remaining port of tee.
4. Install a 1/2-14 pipe to 7/8-14, 37° flare adapter
(Aeroquip #2021-8-10 or equivalent) in the
hydraulic tank fill port.
5. Connect the flowmeter “OUT” line to the adapter.
6. Completely open the flowmeter load valve.
7. Set the brake, start the engine and advance the
throttle to 3900 engine RPM.
8. Read/record no load flow. No load flow should be
4.0 gpm (15.14 lpm).
•
If flow is in specified range, proceed with Step 9.
•
If flow is lower than specified, engine RPM not
correct or pump is faulty.
9. Slowly close the flowmeter load valve until 1800
psi (12411 kPa) is obtained. Record flow.
10. Subtract flow in Step 9 from flow in Step 8.
Example:
4.0 gpm (15.14 lpm), Step 8 @ 3900 engine RPM
4.0 gpm (15.14 lpm), Step 9
0.0 gpm (0.0 lpm) leakage
•
If leakage is 1/2 gpm (1.89 lpm) or less, pump is
okay, proceed with Step 11.
•
If leakage is 1/2 to 1-1/2 gpm (1.89 to 3.78 lpm),
the pump is marginal.
•
More than 1-1/2 gpm (3.78 lpm) leakage will
noticeably reduce performance. The pump may
have to be repaired or replaced (Section 8D).
11. Continue closing flowmeter load valve until flow
drops off and pressure stays constant.
•
Relief set at 2000 psi ± 10% (12411 to 15169
kPa), relief is okay, proceed with Step 12.
•
Relief does not open in specified range, pro-
ceed with Step “a” below.
a. Remove the acorn nut from side of valve.
b. Turn screw 1/8 turn, clockwise (CW) increases
pressure or counterclockwise (CCW) to
decrease pressure. Replace acorn nut.
c. Set the brake, start the engine and advance
the throttle to 3900 engine RPM.
d. Push lift valve lever forward into the lower posi-
tion and hold.
e. Slowly close the flowmeter load valve until
1800 psi (2441 N.m) is obtained, read/record
flow.
•
Relief should be set at 2000 psi ± 10%
(12411 to 15169 kPa). Repeat Steps 11a
and 11b above until correct pressure is
obtained.
•
If pressure can not be obtained, valve may
be faulty, replace.
12. Open tester load valve and shut down engine.
TOP SELECTOR VALVE TEST
(See Figure 8J-13)
NOTE
A pump test should be performed before pro-
ceeding with a selector valve test.
13. Reconnect pump section 1 outlet line to tee.
14. At connection manifold, disconnect line 8 from
port 7.
15. Put high/low speed selector lever in low.
16. Pull selector valve knob up.
17. Completely open the flowmeter load valve.
18. Set the brake, start the engine and advance the
throttle to 3900 engine RPM.
19. Slowly close the flowmeter load valve until 1800
psi (12411 kPa) is obtained. Record flow.
20. Subtract flow in Step 19 from flow in Step 9.
Example:
5.0 gpm (18.93 lpm), Step 9 @ 3900 engine RPM
4.5 gpm (17.04 lpm), Step 19
0.5 gpm (1.89 lpm) leakage
•
If leakage is 1/2 gpm (1.89 lpm) or less, pump is
okay, proceed with Step 21.
•
If leakage is 1/2 to 1 gpm (1.89 to 3.78 lpm), the
pump is marginal.
•
More than 1 gpm (3.78 lpm) leakage will notice-
ably reduce performance. The valve may have
to be replaced.
21. Open tester load valve and shut down engine.
HYDRAULICS
SECTION 8J. INSTRUMENT TEST
8J-19
8J
!
CAUTION
DO NOT exceed 2500 psi (17237 kPa) during
this test.