(b)
Disconnect the elbow from the front spar of the wing.
NOTE: It is recommended the nut and grommet not be removed from the elbow to avoid possible elbow breakage.
(c)
Carefully pull the wiring out of the conduit.
C. Wiring Inspection Procedure
(1)
If the Teflon sleeve is installed on the wiring (SB 28A1120, Revision 3), look carefully to make sure that there are no holes in the Teflon sleeve.
(2)
If there are no holes in the Teflon sleeve, the inspection is complete.
(a) Do this task: Wiring Installation Procedure.
(3)
If there are holes in the Teflon sleeve, then remove the Teflon sleeve (SB 28A1120), to do an inspection of the wiring.
(4)
Look carefully at the part of the electrical cable installed in the conduit.
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(a) If the red, yellow, blue, and/or green wire can be seen through the outer jacket of the electrical cable, then the cable must be replaced. Do not make repairs to the part of the electrical cable housed in the conduit.
NOTE: There are two options on where the new cable is spliced to the cable.
1) Splice it where it joins the main wire bundle on the front spar.
2) Splice it where the electrical cable is now spliced in the fuselage.
Do not put a splice in a resulting location inside the conduit or in an elbow. Ensure splices and all wiring are a minimum of two inches from the control cables. Make the splices (including staggering them) as shown in SWPM 20-30-12. If wires are spliced at the front spar, then the procedure for a moisture proof splice in a fuel vapor area must be used. Also, the splice must be after (away from the direction of the boost pump) the first wire clamp on the front spar. This will permit the Teflon sleeve (installed below) to go through the wire clamp. If the electrical cable is spliced in the fuselage, then use a general purpose slice. Install the cable as shown in SWPM 20-10-11.
NOTE: Refer to SB 28-1120 for acceptable wiring substitutions.
(b) If there is any indication of electrical arching or exposed copper wire on the electrical cable, one of the following two options must be done.
NOTE: Arcing can show as very small blackened holes in the insulation, or as deformation or pitting of the copper wire. Worn areas with a black material around the edge is not a sign of arching. The black material is aluminum oxide.
1) Option 1 a) Before the next flight, replace the section of the electrical conduit where the arching occurred. 2) Option 2 a) Perform an electrical conduit leak test.
(5)
If fuel is seen and/or smelled on the electrical cable, then the leak must be located and repaired.
(a) If the leak is due to damage to the conduit, then replace the damaged conduit.
(6)
If the electrical cable does not have any damage, install it again.
D. Wiring Installation Procedure
(1)
Use compressed air (30 psi maximum) to blow dirt out of the conduit.
(2)
Disconnect the string from the wiring.
(3)
Remove loose dirt from the electrical cable with a rag.
(4)
Install a Teflon sleeve over the electrical cable.
NOTE: The sleeve must cover the part of the electrical cable inside the conduit. Make the sleeve sufficiently long to go through one wire clamp after each end of the conduit.
(5)
On airplanes with a single case ground wire, do not put the case ground wire in the sleeve.
(6)
If installing a non-jacketed electrical cable, then install two Teflon sleeves on it. Do the following steps to install two sleeves:
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