Top Air TA1200, Руководство оператора и список запасных частей

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3-4
Maintenance
An open-center system uses a fixed-
displacement pump, and requires that
the operator keep the engine speed
relatively constant to ensure adequate
flow to the pump. This type of system is
common on older, lower horsepower
tractors.
1. Do not install a flow limiter or orifice
on the pump.
2. Loosen jam nut on motor needle
valve and back out needle valve 3 or
4 turns counterclockwise.
This system uses a variable-
displacement, constant pressure pump,
and is typically found on Deere 20, 30,
40, and 50-series tractors. A restrictor is
used with this system to protect the
pump from over-speeding.
1. Install restrictor orifice in pump inlet.
2. Connect hydraulic hoses to tractor
as described in the OPERATION
SECTION of this manual.
3. Close motor needle valve by
loosening jam nut, screwing needle
valve clockwise until seated, then
tightening lock nut.
4. Adjust tractor flow control to its
minimum setting.
5. Move hydraulic lever to RETRACT to
start pump.
6. Close AGITATION CONTROL valve
after pump primes and begins to
develop pressure.
7. Adjust tractor flow control until the
desired pressure is reached, up to a
maximum pressure of 120 psi.
NOTE: If sufficient pressure cannot be
reached, it may be necessary to enlarge
the restrictor orifice. To do so, remove
orifice and drill hole to a slightly larger
size. Do not run the pump without a
restrictor installed. Consult with dealer or
factory prior to restrictor modification.
IMPORTANT: Do not run pump for
extended periods with outlet flow fully
blocked. Overheating and pump
damage can result.
•
Pressure Compensating
Closed-Center System
•
Open-Center System