Piper Arrow IV Turbo Maintenance Manual page 646

MAINTENANCE OF HARNESS.
1. To replace contact springs, spring retainer assemblies or insulating sleeves, proceed as follows:
A. Using a Scintilla 11-7073 Needle or a mechanical pencil with the lead retracted, hook the end of
the contact spring as shown in Figure 74-31.
B. Using the needle or pencil, unscrew the spring.
C. Slide insulating sleeve and spring retainer assembly off end of lead assembly.
D. Replace defective component and reassemble as follows:
(1) Fabricate a tool as shown in Figure 74-32 for installing the insulating sleeves over cable
terminals.
(2) Push the tool through insulating sleeve and spring retainer assembly as shown in Figure 74-33.
Screw the cable terminal into the tool.
(3) Work insulating sleeve and spring retainer assembly into position over the cable and unscrew
the tool. Install contact spring on cable terminal.
It may be necessary to lubricate cable and insulating sleeve with
a thin film of MC 200 (200,000 centi-stokes) or commercial grade
alcohol to facilitate assembly.
2. To replace one of the lead assemblies, proceed as follows:
A. Remove clamps and brackets from applicable lead assembly. Cut cable ties from assembly and
discard.
B. Cut off condemned lead flush with outer surface of cable outlet plate.
C. Grip eyelet of lead with a pair of pliers and pull short length of conductor out of grommet and
cable outlet plate.
D. Using a 3 inch long, 0.270 inch diameter drift, applied at outer surface of plate, drive out tapered
ferrule and remaining pieces of insulation and shielding.
E. To determine what length the new lead assembly should be cut to, proceed as follows:
(1) Measure the length of the condemned lead assembly. Move coupling nut back on lead
assembly and measure from outer end of ferrule at spark plug end. (Refer to Figure 74-34 )
(2) To length determined in Step (1), add 1-3/4 inches.
Spare part leads are supplied in various lengths. Use a lead
which is longer than, but nearest to, the desired length.
F. Cut lead assembly to the length determined in Step E. Mark ferrule on spark plug end of lead with
a metal stamp, scribe or rubber stamp to correspond with correct cylinder number.
G. Starting at spark plug location, thread new cable through grommets and clamps as necessary for
correct routing of cut end of cable to magneto location.
H. Using electrician's scissors, carefully remove 1.250 inch of outer braid from end of lead. (Refer to
Figure 74-35.)
Effectivity
PA-28RT-201
PIPER AIRCRAFT
PA-28RT-201 / 201T
MAINTENANCE MANUAL
—CAUTION—
Use care not to nick or cut insulation when removing braid.
—NOTE—
—NOTE—
3E18
74-21-02
Page 74-33
December 1, 1978