(6)
Release the pressure in the hydraulic system (Ref par. 5).
S 032-167
(7)
Remove the transmitter for the hydraulic fluid quantity (AMM 29-33-01/401).
(8)
Install the blanking plate on the reservoir.
S 862-166
S 492-168
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S 962-169
(9)
Replace the filter element for the return module (AMM 29-11-29/201).
S 172-473
(10)
Flush the return line:
(a)
Disconnect the supply hose from the system demand pump.
(b)
Connect a drain hose to the supply hose for the demand pump.
(c)
Put the end of the drain hose into the container to catch the hydraulic fluid.
(d)
Connect the pressure line of the service cart to the ground service disconnect on the return module.
(e)
Flush the return line for 40 seconds with a flow of 30 gpm at 60 psig.
(f)
Make sure approximately 20 gallons (80 liters) of hydraulic fluid go through the return line.
(g)
Remove the drain line from the supply hose on the demand pump.
(h)
Connect the supply hose to the demand pump.
(i)
Push the HYD switch on the EICAS display select panel to see the HYD synoptic display.
(j)
Make sure the HYD synoptic shows the shutoff valve for the hydraulic supply is open.
(k)
Disconnect the supply hose from the EDP.
(l)
Connect the drain hose to the EDP supply hose.
(m)
Flush the return line for 40 seconds with a flow of 30 gpm at 60 psig.
(n)
Make sure approximately 20 gallons (80 liters) of hydraulic fluid go through the return line.
S 172-181
(11)
If the system has an auxiliary AC hydraulic pump, flush the return line for the auxiliary AC pump:
(a)
Disconnect the supply hose from the auxiliary AC pump.
(b)
Connect a drain hose to the supply hose.
(c)
Put the end of the drain hose in the container to catch the hydraulic fluid.
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MAINTENANCE MANUAL
(d)
Flush the return line for 3 seconds with a flow of 10 gpm at 60 psig.
(e)
Make sure approximately 0.5 gallons (2 liters) of hydraulic fluid go through the return line.
(f)
Connect the supply hose to the AC auxiliary pump.
S 092-474
(12)
Disconnect the hydraulic service cart:
(a)
Disconnect the drain hose from the EDP.
(b)
Connect the supply hose to the EDP.
(c)
Disconnect the hydraulic service cart from the return module.
S 682-185
(13)
Drain the hydraulic reservoir.
S 092-186
(14)
Remove the blanking plate from the reservoir.
S 432-187
(15)
Install the transmitter for the hydraulic fluid quantity (AMM 29-33-01/401).
S 612-188
(16)
Do this task: "Hydraulic Reservoir Servicing" (AMM 12-12-01/301).
S 862-189
(17)
Pressurize the pneumatic system (AMM 36-00-00/201).
S 792-248
(18)
Examine the supply hose connections and the return module for leakage.
(a)
If you find leakage, repair the cause of it.
(19)
Release the pressure in the pneumatic system (AMM 36-00-00/201).
