TM 5-3805-248-23-2
HYDRAULIC SYSTEM FLOW METER TEE TEST AND MAINTENANCE - CONTINUED
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COMPARISON OF AERATION AND CAVITATION TESTS - CONTINUED
(3)
Check suction line at pump for air leaks.
(a) Using an oil can, apply hydraulic fluid to suction line and connections.
(b) If fluid is sucked in, there is a leak in the line, tighten connections or replace lines.
(c) If no leakage is present, go to step 4.
(4)
Remove and disassemble hydraulic implement pump.
(a) If hydraulic implement pump is worn, damaged or defective; service or replace. Refer to WP 0322 00.
b.
Flow differential suddenly becomes lower at one test between Tests 17 through 23 but remains constant for follow-
ing tests (at higher RPMs). Check the implement pump for cavitation (restriction in suction line). Inspect suction
line and hydraulic tank for blockage. If no blockage is found, proceed to Blocked Circuit Tests, H.
BLOCKED CIRCUIT TESTS
If the System and Pump Tests indicate leakage in control valves or cylinders, a Blocked Circuit Test is performed.
System Oil Temperature (Start).
1.
a.
Open manual load valve on flow meter fully.
b.
Start engine and run at 1,900 RPM. Move ejector control lever into FORWARD position.
c.
Record oil temperature. Refer to Table 3. System oil temperature should be between 145 and 155F (63and
68C).
Ejector Forward Flow Rate (Leakage Rate).
2.
a.
Block ejector circuit with a blocking plate at circuit line.
b.
Open manual load valve on flow meter fully.
c.
Start engine and run at 1,900 RPM. Move ejector control lever into FORWARD position.
d.
Slowly adjust manual load valve on flow meter for a pressure of 1,000 psi (6,895 kPa).
e.
Record flow rate. Refer to Table 3. Correct ejector forward flow rate is 68 gpm (257 l/min).
Ejector Return Flow Rate (Leakage Rate).
3.
a.
Block, ejector circuit with a blocking plate at circuit line.
b.
Open manual load valve on flow meter fully.
c.
Start engine and run at 1,900 RPM. Move ejector control lever into RETURN position.
d.
Slowly adjust manual load valve on flow meter for a pressure of 1,000 psi (6,895 kPa).
e.
Record flow rate. Refer to Table 3. Correct ejector return flow rate is 68 gpm (257 l/min).
Bowl Raise Flow Rate (Leakage Rate).
4.
a.
Block bowl circuit with a blocking plate at circuit line.
b.
Open manual load valve on flow meter fully.
c.
Start engine and run at 1,900 RPM. Move bowl control lever into RAISE position.
d.
Slowly adjust manual load valve on flow meter for a pressure of 1,000 psi (6,895 kPa).
e.
Record flow rate. Refer to Table 3. Correct bowl raise flow rate is 68 gpm (257 l/min).
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