Piper COMANCHE PA-24-180 Service Manual page 343

7A-14. Installation of Propeller. (McCauley) (PA-24-250) (Refer to Figure 7A-1.)
CAUTION
Ascertain the Master Switch and Magneto Switch are in the "OFF' position
and the Mixture Control is in the "IDLE-CUT-OFF' position.
a. Position the spinner bulkhead ring (5) against the starter ring gear support (4) so that one arrow lines
up with the TCI on the front face of the support.
b. Secure the spinner bulkhead to the starter ring gear support with 12 bolts ( I ), 12 nuts (3), and 24
washers (2) (one under the bolt head and one under each nut). Carefully tighten nuts uniformly, to torque
limits, shown in Table VIIA-I.
c. Clean the propeller and engine flanges.
d. Observe the starter ring gear to make sure it is mounted properly on the engine crankshaft flange.
The crankshaft flange is stamped with "0" mark and the starter ring gear is likewise identified by an "0"
mark. Upon installation of the starter ring gear, the markings shall be mated to insure proper installation.
e. Insert the "0" ring in the groove of the propeller (7) hub bore. Make sure that the "0" ring is ,ot
twisted and is liberally coated with clean lubricating oil.
NOTE
Some McCauley propellers may be found in use with a counterbore in the
hub instead of an "0" ring groove. When installing these propellers, always
insert the "0" ring in the counterbore and push it to the bottom. Never slide
the "0" ring on the crankshaft pilot.
f.
Raise the propeller and line up the arrows on the hub flange outer diameter with the short bushing in
the crankshaft flange. Engage the pilot in the hub, making sure that face of hub flange is parallel with the face
of the crankshaft flange, then push the propeller in. Make sure that the bolt holes engage the bushings.
CAUTION
It is important that the propeller be seated against the crankshaft flange with
a straight push. Rotating or cocking it on will cause damage to the "0" ring
and oil leakage will result. Particular care must be taken while installing
hubs having a counterbore to prevent damaging the "0" ring or displacing it
so that it is lodged between the flange faces. The latter condition will be
indicated by, nontracking of the blades immediately after installation.
g. Slide washers (9) on bolts (8) and tighten bolts uniformly all around to the torque limits ofTable
VIIA-I and safety wire bolts.
h. Check blade track. (Refer to paragraph 7A-22.)
i.
Slide spinner (10) over the propeller, align screw holes with the nuts in the bulkhead, and install
washers (12) and screws (II). Tighten to the torque given in Table VIIA-I.
Revised: 8/15/98 POWER PLANT
PA-24-250 AND PA-24-260
2C9
PIPER COMANCHE SERVICE MANUAL