Attached is another way from service manual to purge air from system without placing on jacks.
5-128. BLEEDING TIME-DELAY VALVE.
The
Time-delay valve in the Power Pack may be purged of
air by operating the engine-driven pump, or the
Hydro Test may be used.
2.
Make sure reservoir is full.
b
Start engine and let run at 1000 rpm, or connegt
Hydro Test in accordance with paragraph 5-125
Place landing gear handle in the down position
and hold for approximately one minute, while turning
the master switch OFF
until doors open,
then ON un-
til doors close.
d.
Repeat step "c" four times, waiting one minute
between steps.
e.
Check that time-delay operates properly by mov-
ing gear handle sharply to the down position and re-
cording time as handle returns to neutral.
NOTE
The time delay between closing of the landing
gear doors and releasing the landing gear
handle to neutral should be between 3 and 9
seconds at room temperature. Colder temper-
atures will cause a longer delay.
i.
Shut down engine, or disconnect Hydro Test in
accordance with paragraph 5-126.
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