Piper COMANCHE PA-24-180 Service Manual page 472

7C-57. Removal Of Haim.
a
Disconnec the cdmups
r secure the waes to the engine and accessories.
b. Loosen the coupling nunt a the spurk plug and remove he insulaon from the sprk plug barrel
weL Use caution when withdrawing the insulaor not to da
ge the inslitor spring.
c. Place a guard over the hanes imularor.
d. Remove the hrneu assembly uminal plae from the mgneo.
e.
Remove the engine blffle plate h rceire the hane
ass mbly.
f.
Remove the harnem from the airplane.
7C-58. Ialmldion Of Hanem. Before imling barn
on magneo, check mating surfaces for cleanlines.
Spray enire face of grommet with
light coat of Plastic Mold Spry, SM-0O-TH Silicone Spray or
equivalent. Thi will prevent hanes grommet from sticking to magnero disibutor block.
a.
Place the haness erminal plate on the mgneto and tighten nunt uound the plae alternately to
rt cover squarely on magnero. Torque screws to 18 to 22 inch pounds.
b. Route ignition wires to their respective cy' 'en.
c.
Clamp the harness assembly m position and replace the engine baffle place.
d. Connect rhe leads to the spark plugs.
7C-59. Spark Plugs.
7C-60. Removal Of Spark lugs.
a.
Looen the coupling nut on the haness lead and remove the termina insulator from the spark plug
barrel well.
NOTE
When withdrawing the igition cable lead connection from the plug,
care must be taken to pull the lead straght out and in line with the
center line of the plug barrel; otherwise, a side load will be applied
waich frequently results in damage to the barrel insulacor and
connector. If the lead cannot be removed easily in this manner, the
resisting contact between the neoprene collr and the barrel insulator
will be broken by a rotary rwisting of the collar. Avoid undue distortion
of the collar and possible side loading of the barrel insulaor.
b.
Remove the spark plug from the engine. In the course of engine operation, carbon and other
combustion products will be deposited on the end of the spark plug and will penetrate the lower threads to
some degree. As a result. greater torque is frequently required for removing a plug than for its installation.
Accordingly, the torque limitations given do not apply to plug removal and sufficient torque must be used
to unscrew the plug. The higher torque in removal is not u deimmental as in insallaton, since it cannot
strerch the threaded secton. It does. however. impose a shearnng load on this section and may. if
suffciently severe, produce a failure n this location.
POWER PLANT
ISSUED: 8/18/72
2H18
PIPER COMANCHE SERVICE MANUAL