Piper SEMINOLE PA-44-180, Maintenance Manual

Page: 77 / 881

— WARNING —
DO NOT RELEASE AIR BY REMOVING THE STRUT VA LVE CORE OR
FILLER PLUG. DEPRESS THE VA LVE CORE PIN UNTIL THE STRUT
CHAMBER PRESSURE HAS DIMINISHED.
— CAUTION —
CLEAN ALL DIRT AND FOREIGN PA RTICLES FROM AROUND THE
FILLER PLUGS WITH COMPRESSED AIR AND/OR WITH A QUICK
DRYING SOLVENT.
If the strut has less tube exposure than prescribed, determine whether it needs air or oil by rocking the airplane. If
the oleo strut oscillated with short strokes (approximately one inch) and the airplane settles to its normal position
within one or two cycles after the rocking force is removed, the oleo strut requires inflating. Check the valve
core and filler plug for air leaks, correct if required, and add air. If the oleo strut oscillates with long strokes
(approximately three inches) and the airplane continues to oscillate after the rocking force is removed, the oleo
struts require fluid. Check the oleo for indications of oil leaks, correct if required, and add fluid. For repair
procedures of the landing gear and/ or oleo struts, refer to Chapter 32 of this manual.
FILLING NOSE GEAR OLEO STRUT.
The nose gear should be serviced with MIL-H-5606 hydraulic fluid only. The nose gear is filled as follows:
1. Raise the airplane on jacks as explained in Chapter 7, and place a pan under the gear to catch spillage.
2. Remove the cap from the air valve and release the air pressure by depressing the valve core.
3. Remove the valve from the filler plug at the top of the strut housing.
4. Fully compress the piston tube and fill the strut with hydraulic fluid to the level of the hole for the valve .
5. Remove the core from the valve and install the valve back in the filler plug. Torque valve 350 to 400
inch-pounds.
6. Attach one end of a clean plastic hose to the valve and submerge the other end in a container of clean
hydraulic fluid, making sure the end of the hose is below the surface of the fluid
— Note —
An air tight connection is necessary between the plastic tube and the valve stem.
Without such a connection, a small amount of air will be sucked into the oleo strut
during each sequence, resulting in an inordinate amount of air bubbles and prolonged
filling operations.
7. Fully compress and extend the piston tube, thus expelling any air trapped within the strut chamber. By
watching the fluid pass through the plastic hose, it can be determined when the strut is full and no air is
present in the chamber.
8. When air bubbles cease to flow through the hose, compress the piston fully and remove the hose from the
valve stem.
PA - 4 4 - 1 8 0 / 1 8 0 T
AIRPLANE MAINTENANCE MANUAL
1 2 - 2 1 - 0 2
Page 12-05
Revised: May 15, 1989
1D5
PIPER AIRCRAFT