Pump Running Intermittently After Gear Has Retracted; Gear Stops Part Way Up, But Pump Continues To Run; All Gears Fail To Free Fall - Piper PA-44-180 SEMINOLE Maintenance Manual

CHART 2902. TROUBLESHOOTING HYDRAULIC SYSTEM (cont.)
Trouble
Pump running intermittently after
gear has retracted.
Gear stops part way up, but pump
continues to run.

All gears fail to free fall.

PIPER AIRCRAFT
PA - 4 4 - 1 8 0 / 1 8 0 T
AIRPLANE MAINTENANCE MANUAL
Cause
Leakage of high pressure check
valve.
Internal leakage of system.
External leakage of system.
Pump high pressure relief valve
out of adjustment.
Internal leakage of system.
Hydraulic fluid in reservoir
below operating level.
Free fall valve fails to open.
2C5
Remedy
(2) Remove pump and replace
check valve.
Check free fall valve for internal
leakage.
Check gear actuating cylinders
for internal leakage.
Check free fall valve for external
leakage.
Check gear actuating cylinders
for external leakage.
Check for broken or damaged
hydraulic lines.
(2) P restolite pumps
Return Oildyne pumps to Piper
A i r c r a f t v i a l o c a l P i p e r
d i s t r i b utor for overhaul.
Replace pump.
Check free fall valve for internal
leakage.
Check gear actuating cylinders
for internal leakage.
Check for broken or damaged
hydraulic lines.
Fill reservoir with hydraulic
fluid.
C h e c k v a l v e a n d c a b l e s
c o n n e ctions. Replace valve or
connect cables.
Page 29-10
Revised: June 20, 1995
only.
29-02-00