Rockwell Commander 112 - Page 71

SECTION m
HYDRAULICS
TROUBLE
Hydraulic power pack
pump
stops during gear
retrac tion/ extension.
Hydraulic
power pack
pump
fails to shut off
after gear retraction.
Hydraulic power pack
pump fails to shut off
after gear extension.
Intermittent hydraulic
power pack pump opera-
tion after gear has
retracted.
Landing gear doesn't
fully retract. Hydraulic
power pack pump
con-
tinues to run.
Slow gear extension
(normal and emergency).
Gear will not extend.
MAINTENANCE MANUAL
PROBABLE CAUSE
Landing gear ACT circuit breaker opens.
Landing gear SEL circuit breaker opens.
Up gear logic relay defective.
Uplock position switch out of adjustment
and/or hydraulic actuating switches out of
adjustment on model 112 (S/N thru 380).
Leakage in system.
Uplock position switch and/or hydraulic
actuating switch defective.
Hydraulic pre ssure switch set
incorrectly, or defective (S/N
381 and subsequent).
Pump extension relay sticking.
Downlock position switch out of adjustment
and/or hydraulic actuating switch out of
adjustment on model 112 (S/N thru 380) 0
Downlock position switch and/or
hydraulic actuating switch defective.
Hydraulic pre ssure switch
set incorrectly, or defective
(SiN 381 and subsequent).
Leakage in pump.
Leakage in
system.
Hydraulic power pack pump high pres-
sure relief valve out of adjustment.
Leakage in system.
Hydraulic power pack vent port
restricted.
REMEDY
ROCKWELL
COMMANDER
112/B/TC /TCA
Check visually. Reset circuit
breaker.
Check visually. Reset circuit
breaker.
Check relay. Replace defective
relay.
Check switches individually. Adjust
or replace switch.
Check gear actuating cylinders,
hydrauliC power pack pump and
hydraulic lines. Replace or repair
as required.
Check switch. Replace defective
switch.
Check switch. Reset or
replace defective switch.
Check relay. -Replace defective
relay.
Check switches individually. Adjust
or replace switch. Faulty switch
may be determined by noting which
down light
has not lighted.
Check
switch. Replace defective
switch.
Check switch. Replace defective
switch.
Check switch. Reset, or
replace defective switch.
Check high pressure check valve
and manifold. Replace defective
power pack unit.
Check actuating cylinders and hy-
draulic lines. Replace defective
parts.
Check pump. Replace defective
power pack unit.
Check actuating cylinders and hy-
draulic lines. Replace defective
parts.
Verify vent port washer is free to
rotate and has a minimum clearance I
of 0.06 inch between power pack boss
and bottom of rubber seal washer.
Figure 3-8. Trouble Shooting Hydraulic System (Sheet 2 of 2)
3-14
Change 4
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