Textron JACOBSEN R-311 69166, Техническое руководство по ремонту

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HYDRAULICS
4203781 First Edition 6-27
6
Instrument Test Procedure
Instrument Test Overview
The following tests are specifically designed to approach
hydraulic testing on a system level. Each component
within the system represents a portion of the total system
leakage. An internal leakage percentage for each
component will be calculated and recorded, enabling the
technician to view the system performance issue more
completely. The test results will help the technician to
determine which repairs will best remedy the
performance issue experienced by the machine user.
The internal leakage percentage ranges are as follows:
0–10% = Good
11–20% = Marginal
21% and beyond = Bad
Example: Cutting Unit System Performance
Complaint
The machine operator reports the mower is not cutting
correctly.
Troubleshooting must first be performed to rule out a
cutting unit adjustment issue. Once the issue is known to
be component related, the entire cutting unit system is
tested as outlined. The calculated system leakage is
35%, a result that requires the testing of individual
components. This result can also be interpreted as the
system is 65% efficient.
The remaining components in question are as follows:
front cutting unit pump, front deck valve, right front cutting
unit motor, center front cutting unit motor, and left front
cutting unit motor. Following the procedures as outlined,
test each individual component, then calculate and
record leakage percentages.
The results from this test reveal leakage of 5% in the front
cutting unit pump, 10.5% in the front deck valve, 20% in
the right front cutting unit motor, 5.6% in the center front
cutting unit motor, and 4.4% in the left front cutting unit
motor. Although all the components lend to the overall
circuit leakage, only the right front cutting unit motor,
which is at the extreme end of the marginal range, would
be considered for repair/replacement.
Formulas:
Cutting Unit Motor and Deck Valve
Loaded Flow from previous component – Loaded Flow
from current component / Loaded Flow from previous
component x 100 = Leak Percentage
Circuit and Rear Cutting Unit Pump
No Load Flow – Loaded Flow / No Load Flow x 100 =
Leak Percentage
Calculations:
Circuit Test
No Load Flow = 10 gpm
Loaded Flow = 6.5 gpm
10 – 6.5 / 10 x 100 = Total Circuit Leakage 35%
Front Cutting Unit Pump Test
No Load Flow = 10 gpm
Loaded Flow = 9.5 gpm
10 – 9.5 / 10 x 100 = Front Cutting Unit Pump Leakage
5%
Front Deck Valve Test
Loaded Flow from front cutting unit pump test = 9.5 gpm
Loaded Flow from front deck valve test = 9 gpm
9.5 – 9 / 9.5 x 100 = Front Deck Valve Leakage 5.3%
Left Front Cutting Unit Motor Test
Loaded Flow from front deck valve test = 9 gpm
Loaded Flow from right front cutting unit motor test = 7.2
gpm
9 – 7.2 / 9 x 100 = Right Front Cutting Unit Motor
Leakage 20%
Center Front Cutting Unit Motor Test
Loaded Flow from left front cutting unit motor test = 7.2
gpm
Loaded Flow from center front cutting unit motor test =
6.8 gpm
7.2 – 6.8 / 7.2 x 100 = Center Front Cutting Unit Motor
Leakage 5.6%
Right Front Cutting Unit Motor Test
Loaded Flow from center front cutting unit motor test =
6.8 gpm
Loaded Flow from right front cutting unit motor test =
6.5 gpm
6.8 – 6.5 / 6.8 x 100 = Left Front Cutting Unit Motor
Leakage 4.4%