TYM T233 HST, Руководство по обслуживанию

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13.Slowly depress forward directional pedal and
observe gauge. Gauge should slowly rise to
approximately
130~170kgf/cm
2
(1848~2417psi)
and relief valve will open with an audible
squealing noise if the pressure rise to over 350
kgf/cm
2
(at the Pb port)
14.Repeat same procedure with reverse pedal.
(at the Pa port)
Specifications:
-Pump pressure should reach approximately
130~170kgf/cm2 (1848~2417psi) in either
direction and then relieve.
Results:
-If pressure will not reach
130~170kgf/cm2
(1848~2417psi) in either direction, check charge
Pressure.(SEE ”CHARGE PUMP PRESSURE
TEST on page 13 )
-If charge pressure is good and hydrostatic pump
pressure will not get up to relief pressure
hydrostatic pump is worn or damaged.
-If pressure reaches 130~170kgf/cm
2
in one
direction and not the other, one of the relief
valves is defective or the seat is leaking.
Procedure:
1.Park tractor on a level surface and set park
brake.
2.Turn key switch to OFF position.
3.Shift transmission to NEUTRAL.
IMPORTANT:Make sure to relieve system
pressure before loosening any system lines or
hoses.
4. Cycle all controls to relieve any pressure that
may be in the hydraulic system.
Pc
Pa
Pb
3.CHARGE PUMP PRESSURE TEST
Reason:
To ensure that charge pump is operating at
specified pressure to supply oil to hydrostatic
pump.
Equipment :
Refer to the 13 page
5.Underneath the tractor,at the front of the tunnel
,locate the hydrostatic transmission, Remove the
plug in the charge pressure test port.
6.Assembled test equipment as shown and install
to test port.
7.Start engine and run at high idle (2500~2700rpm )
8.Check pressure reading gauge.
Specifications : at the Pc port
Charge Pressure------8 ~ 10
kgf/cm
2
(113~142psi).
Results:
-Charge pressure should reach 8 ~ 10
kgf/cm2
(113~142psi). cannot obtained; the mesh inlet filter
may be restricted, the suction line may be restricted
or leaking air, or front hydraulic pump may be
defective
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