Cushman TURF-TRUCKSTER, Service & Repair Manual

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AS A SAFETY REMINDER
•
Follow the procedures one step at a time.
•
Observe all NOTES, CAUTIONS and WARNINGS.
•
Pay attention to what you are doing. Work with a
safety conscious attitude.
•
Use care working with HOT oil.
•
Wear safety glasses at all times.
•
Keep hands and feet away from the moving parts.
•
Engine must be shut off and attachments lowered to
ground when making adjustments or hydraulic con-
nections unless otherwise specified in the test
instructions.
PRELIMINARY CHECKS
The following preliminary checks should be made
before performing any tests.
1. The reservoir should be checked for proper level,
the presence of water (noted by a cloudy or milky
appearance), air (noted by a foaming appear-
ance), or a rancid odor indicating excessive heat.
If any of the above symptoms appear, or if the
hydraulic oil becomes contaminated, or after a
major component failure, the oil should be
changed and system flushed.
NOTE
Use only the recommended hydraulic oil (see
Section 11 — Preventive Maintenance). Always
change the filter when changing the oil.
The Filter should be changed after the initial
50 hours of operation. Thereafter, the filter
should be changed approximately every 500
hours.
2. Check all lines and fittings for leakage and tighten
as necessary (see Section 8C).
3. Eliminate all possible mechanical problems first
before starting the hydraulic tests.
STANDARD HYDRAULIC SYSTEM
PUMP FLOW TEST (See Figure 8J-2)
1. At the pump, remove the outlet line from pump
section 1. Plug line.
2. Install a tee to pump outlet port.
3. Connect 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. Read/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
3.5 gpm (13.25 lpm), Step 9
0.5 gpm (1.89 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 5.68 lpm),
the pump is marginal.
•
More than 1-1/2 gpm (5.68 lpm) leakage will
noticeably reduce performance. The pump may
have to be repaired or replaced (Section 8D).
11. Continue closing load valve until the flow drops off
and pressure stays constant, read/record pressure.
•
Relief valve is set at 2500 psi ± 10% (15514 to
18962 kPa), proceed with Step 12.
•
If relief valve does not open in specified range,
pump should be replaced.
12. Open the flowmeter load valve and shut down
engine. Proceed with Step 13, “SELECTOR VALVE
TEST”.
HYDRAULICS
SECTION 8J. INSTRUMENT TEST
8J-2
!
CAUTION
DO NOT exceed 3000 psi (20685 kPa) during
this test.