1·51. Draining Fuel System. Drain the fuel from the system by opening the drain valve at the bottom of. fuel strainer bow I. or removing the bowl. PIPER COMANCHE SERVICE MANt:AL 1-52. 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 electrolvte that would lead to corrosion. The securitv of all electrical connections should be checked a- 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. 1-54. Ox~'gen System. 1-55. Description of Oxygen System. The oxygen system for the PA-24 consists of an oxygen c~ linder and regulator. filler vain. pressure gauge. outlets and masks and an 0]'\ OFF control mounted on the instrument panel. The stationary cylinder is located aft of the baggage area on the left side ofthe fuselage. The cylinder used is an ICC or DOT 3AA 1800 classification with a 63 cubic foot capacity at a working pressure of 11'00 psi. High pressure oxygen is routed from the cylinder and regulator to the pressure gauge mounted in t he upper ponion of I he aft cabin bulkhead.
Low pressure oxygen is routed from the cylinder and regulator to the OUI Jets and masks whenever the control knob is pulled to the O~ position. Each outlet has a spring loaded valve which prev ents the now of oxygen until a mask hose is engaged into the outlet. 2-5tl. Troubleshooting. Troubles peculiar to the oxygen system are listed in Table II-V along \\ ith probable causes and suggested remedies. 2-57. Ox~'gen System Safety Precautions. The utmost care must be exercised in servicing. handling and inspection of the oxygen system. Comply with the following precautions: 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. WAR~I~G The presence offoreign 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. c. "ner 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. Lse Ribbon Dope Thread Sealant (Perrnacel 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 mto the lines. HANDLI!I\G ASD SERVIn. icu REVISED: 11 /1/82