Piper PA-24 Comanche, Service Manual

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PIPER COMANCHE SERVICE MANUAL
II - HANDLING AND SERVICING 04/01/09
1C12
2-52.
Electrical System.
2-53.
Servicing Electrical System.
Servicing the electrical system involves adding distilled water to the battery to maintain correct
electrolyte level, checking cable connections and checking for any spilled electrolyte that would lead to
corrosion. The security of all electrical connections should be checked as well as the operation of all
lights, general condition of generator or alternator and starter. All electrical wires should be inspected for
chafing and bare wires. For detailed information on this system. refer to Section IX of this manual.
2-54.
Oxygen System.
2-55.
Description of Oxygen System.
The oxygen system for the PA-24 consists of an oxygen cylinder and regulator, filler valve, pressure
gauge, outlets and masks and an ON / OFF control mounted on the instrument panel. The stationary
cylinder is located aft of the baggage area on the left side of the fuselage The cylinder used is an ICC or
DOT 3AA 1800 classification with a 63 cubic foot capacity at a working pressure of 1800 psi. High
pressure oxygen is routed from the cylinder and regulator to the pressure gauge mounted in the upper
portion of the aft cabin bulkhead. Low pressure oxygen is routed from the cylinder and regulator to the
outlets and masks whenever the control knob is pulled to the ON position. Each outlet has a spring
loaded valve which prevents the flow of oxygen until a mask hose is engaged into the outlet.
2-56.
Troubleshooting.
Troubles peculiar to the oxygen system are listed in Table II-V along with probable causes and suggested
remedies.
2-57.
Oxygen System Safety Precautions.
The utmost care must be exercised in servicing, handling and inspection of the oxygen system. Comply
with the following precautions:
WARNING: THE PRESENCE OF FOREIGN MATTER IN THE HIGH PRESSURE LINES CAN
CAUSE AN EXPLOSION. WHEN COMING IN CONTACT WITH OXYGEN
EQUIPMENT KEEP HANDS, TOOLS AND CLOTHING CLEAN - HOSPITAL CLEAN.
a. Keep all oxygen system components free from oil, grease. gasoline and all other readily
combustible substances.
b. Do not allow foreign matter to enter the oxygen lines.
c. Never attempt to repair or repaint oxygen equipment.
d Keep fire and heat away from oxygen equipment. Do not smoke while working with or near oxygen
equipment, and take care not to generate sparks with carelessly handled tools when working on the
oxygen system.
e. Never allow electrical equipment to come in contact with the oxygen cylinder.
f. Use Ribbon Dope Thread Sealant (Permacel 412) on male ends of fittings only. Wrap thread in
direction of thread spiral. beginning with the second thread on the fitting. Avoid getting any sealant
into the lines.