Piper COMANCHE PA-24-180 Service Manual page 444

2. The low pitch stop adjustment is nade by · * crew in the noe of the propeller cylinder.
Roaing the screw clockwise incres the low pitch and reduce the sric
RPM by about 100 RPM for
each half tun; or vice vera.
b. After the low pitch stop has been djusced for proper blade ile, the governor should then be
adjusted to obtain maximum rated engine RPM during tke-off climb a decribed in paagraph 7C-17.
7C-13. Blade Trck. Blade rnck is the ability of one blade tip to follow the other. while routing. in
almcar the same plane. Excenive difference-in blade ack - more than .0625 inch - may be a indication of
bent blades or improper propeller installaion. Check blade trck as follows:
a. With the engine shut down and blades verical, ecure to the aircraft a nmooth board just under the
tip of the lower blade. Move the tip fore and aft through its full "bladethake"
ravel, making mall marks
with a pencil at each position. Then center the tip between these mrks and scribe a line on the board for
the full width of the tip.
b. Carefully rote propeller by hand to bring the opposie blde' down. Center the tip and scribe a
pencil line u before and check that lines are nor puraed more than .0625 inch.
c. Propelles having exces blade nck
!
.,id be removed and inspected for bent blades or for par
of sheared "0" ring, or foreign paricles, which have lodged between hub and crankshaft mounting faces.
Bent blades will require repair and overhaul of assembly.
7C-14. Propeller Governor.
7C-15. Removal Of Propeller Governor.
a
Lift the left side panel of the engine cowling.
b. Disconnect control cable from governor control arm.
c. Remove the governor mounting stud nun. It will be necessary to raise the governor as the nu are
being removed before the nuts can be completely removed.
d. Remove the mounting gasket. If the governor is to be removed for a considerable length of time
and another unit is not substituted, it is advisable to cover the mounting pad ro prevent damage caused by
foreign mnter.
7C-16. Installaion Of Propeller Governor.
a. Clean the mounting pad thoroughly making very certain that here are no foreign particles in the
recess around the drive shaft.
b. Place the governor mounting gasket in position with the raised portion of the screen fcing away
from the engine.
c. Align the splines on the governor shaft with the engine drive and slide the governor in position.
d. Ruse governor off mounting pad enough to insall washers and strt mounting nuts. Torque nuts
evenly.
e. Connect the control cable end to the governor control arm.
f. Adjust governor control per paragraph 7C-17.
POWER PLANT
ISSUED: 8/18/72
2614
PIPER COMANCHE SERVICE MANUAL