Oxygen System Leak Tests; Oxygen System Components; Oxygen Cylinder Removal - Piper PA-44-180 SEMINOLE Maintenance Manual

LEAK TESTS.
Solutions recommended for leak testing are Leak-Tec Formula #16-OX, and that available from Scott
Aviation. Refer to the List of Consumable Materials for consumer information.
1. Remove the royalite covers in the baggage compartment and, with the oxygen system turned off, disconnect
the low pressure supply line and connect it to a regulated cylinder charged with dry nitrogen.
Whenever a leak check is performed all fitting connections as well as other
questionable areas, should be inspected.
2. Apply the leak detector solution to the test surface and watch for indication of leakage.
3. Large leaks will produce bubbles immediately, but small leaks will form a white foam in 5 to 60 seconds.
4. With outlets vacated of masks, connect a test pressure gauge to the co-pilot's outlet as described in the
subject paragraph on Inspection and Maintenance. See Figure 35-3.
5. Adjust the regulator on the dry nitrogen cylinder for 100 psi and check for leakage at the outlets.
6. Correct any leaks and wipe off excess leak detector solution.
7. Close the valve on the nitrogen gas tank and insert a Scott plug-in to relieve system pressure.
8. Disconnect test gauge, plug in, and nitrogen tank.
9. If the oxygen cylinder is not to be hooked up or installed immediately, cap and cover the exposed fittings
with new clean plastic bags. Temporarily support lines as needed to prevent damage. Make sure caps and
coverings are as clean as possible.

OXYGEN SYSTEM COMPONENTS.

Keeping in mind the effect of compressed oxygen on materials, oxygen system components must be handled
carefully. Ports on regulators, indicators, and other opened components must also be kept capped or plugged to
prevent ingestion of foreign material. Adjustments or modifications should only be initiated under the auspicious
of the FAA, Piper, or Scott Aviation.
REMOVAL OF OXYGEN CYLINDER. (Refer to Figure 35-1.)
Replacement time for the recharge valve is every 5 years. If the cylinder is being
removed for the 5 year test, it is recommended the valve be removed and/or replaced
at the same time.
The oxygen bottle, located behind the finished bulkhead in the baggage compartment, is secured to a
removable shelf mounted to each side of the fuselage. The tank is mounted such that the regulator-control valve is
on the left side of the aircraft, the same side as the recharge valve. A shroud also covers the regulator end of the
bottle to prevent leaks, should any develop, from filling the aircraft with oxygen. With this in mind, a vent tube
interconnects the shroud with the recharge valve fixture permitting any oxygen to vent overboard.
1. Remove the screws attaching the finished bulkhead to the fuselage bulkhead, and remove the finished
bulkhead.
PIPER AIRCRAFT
PA - 4 4 - 1 8 0 / 1 8 0 T
AIRPLANE MAINTENANCE MANUAL
— Note —
— Note —
2J20
3 5 - 11 - 0 7
Page 35-12
Revised: May 15, 1989