Oxygen Cylinder Installation; Pressure Gauge Removal And Installation; Outlets Removal - Piper PA-44-180 SEMINOLE Maintenance Manual

INSTALLATION OF OXYGEN CYLINDER.
1. Before mounting the cylinder to the shelf. connect the control cable to the control valve-regulator. If the
shelf has been removed reinstall it before continuing. Install teflon tape per prior instructions in this chapter.
2. Position cylinder on shelf and install the pressure lines. Insert tubing into fitting until ferrule seats in fitting.
Tighten the nut by hand and then one quarter turn with a wrench. If fitting is relatively new the nut might be
turned 3/1 of a turn. Follow up by snugging the nut slightly with a wrench.
3. Install the cylinder protective shroud and tighten the clamps securing it to the tank. and valve.
4. Secure the cylinder to the shelf by connecting and tightening the clamps.
5. If vent tube has been disconnected from the shroud make sure it is firmly attached to both the cylinder and
valve shrouds.
6. Make sure all seals are properly in place in the cylinder shroud. Make sure the MS35489-35 seal is in the
bottom of the shroud where the low pressure line comes through. The two seals where the high pressure
lines go into the shroud are MS35489-2 grommet seals.
7. Check pressure and refill bottle as necessary.
8. Inspect for leaks, especially at fittings that have been separated.
REMOVAL AND INSTALLATION OF PRESSURE GAUGE.
1. The pressure gauge is tied into the same high pressure line as the recharge valve, through a tee fitting at the
tank regulator-control valve. The high pressure line connects into the valve such that it actuates a check
valve permitting pressure to the line. Disconnect the high pressure fitting at the tank valve being careful to
only unscrew it a little at a time so as to allow the pressure to bleed off. Cap the lines as soon as possible
after removal.
2. Remove the overhead vent panel and remove instrument from bracket as follows:
A. Disconnect the tube from the fitting at the rear of the instrument.
B. Immediately cap the oxygen line.
C. Snap off the clip securing the instrument in its bracket.
D. If the fitting on the rear of the instrument is to be reused remove, clean threads, and using tape. install
fitting on new gauge. Refer to appropriate section in this chapter.
3. Install gauge as follows:
A. With fitting installed on rear of instrument install gauge in bracket. Make sure clip is properly secure.
B. Remove cap from oxygen line and with teflon tape properly installed, connect the oxygen line to the
fitting.
C. Reinstall fitting in tank.
REMOVAL OF OUTLETS.
1. Make sure the oxygen system is completely turned off. Insert an oxygen mask to release pressure. and
insure the system is off.
2. With a suitable spanner wrench, remove the outer half of the outlet.
3. Remove the screws retaining the trim panel and remove same.
4. The outlet can now be disconnected from the low pressure line(s). Make sure to cap lines immediately after
disconnection.
PIPER AIRCRAFT
PA - 4 4 - 1 8 0 / 1 8 0 T
AIRPLANE MAINTENANCE MANUAL
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2J22
3 5 - 11 - 0 2
Page 35-14
Revised: May 15, 1989