Piper Navajo PA-31 Service Manual page 555

PIPER NAVAJO SERVICE MANUAL
NOTE
Spring in capacitor outlet may cause an indication of a short
to ground if adapter lead is not used. Refer to paragraph
8B-20, step c - Note.
8B-22. HARNESS ASSEMBLY.
8B-23. INSPECTION OF HARNESS.
a. Inspect cover for cracks or other damage. Inspect lead assemblies for abrasions,
mutilated braid or other physical damage.
b. Inspect grommets for tears and eyelets for spark erosion.
c. Disconnect harness coupling nuts from the spark plugs and extract the lead
terminations. Inspect contact springs and compression springs for any damage or distortion.
Inspect sleeves for cracks or carbon tracking.
d. Inspect coupling nuts and elbow assemblies for damaged threads or other defects.
NOTE
Replace any damaged components per instructions given in
paragraph 8B-24.
e. Test continuity of each harness lead using a High Tension Lead Tester. Part No.
11-8888 or 11-8888-1 from Bendix, as follows:
1. Connect black test lead to contact spring and red lead to eyelet of the same lead.
(Refer to Figure 8B-11.)
2. Observe that the continuity lamp illuminates.
f. Test insulation resistance of each harness lead by using the 11-8888 or 11-8888-1
tester as follows:
1. Attach the red high voltage test lead to contact spring of harness lead. (Refer to
Figure 8B-12.)
2. Attach the black test lead to the ferrule of the same harness lead. (Refer to
Figure 8B-12.)
3. Depress PRESS-TO-TEST push-button switch.
4. Observe that indicator lamp flashes and GAP fires simultaneously as long as the
PRESS-TO-TEST switch is held depressed. Whenever indicator lamp flashes and GAP fails to
fire, lead under test is defective and must be replaced.
8B-24. MAINTENANCE OF HARNESS. Minor repairs of the harness assembly, such as
replacement of contact springs, sleeves, compression springs, eyelets, or grommets can be
accomplished with the harness mounted on the engine. Lead assemblies may also be
replaced with harness mounted on the engine unless inaccessibility of installation or number
of leads to be replaced makes it unreasonable.
Reissued: 10/12/79
POWER PLANT
2L9