Section V. G O V E R N O R
9 1 . Governor Cleaning, Inspection, and
a. The centrifugal flyball governor rotates
on a stationary pin driven into the upper part
a. Wash the parts in an approved cleaning
of the timing-gear cover. The governor is
solvent; dry thoroughly.
driven through the governor gear off the cam-
b. Examine the face of the thrust sleeve and
shaft gear at the speed of the crankshaft.
bearing for signs of wear. Examine the bear-
b. The flyweights are hinged to lugs on the
ing end for worn or binding bearing balls. Re-
gear. As the crankshaft speed increases, the
place a worn or defective thrust sleeve and
flyweights are thrown outward by centrifu-
gal force. Hardened pins on the flyweights are
c. Inspect the governor drive shaft for scor-
brought to bear on a sliding sleeve, and the
ing or wear; replace a defective thrust.
movement of the sleeve is transmitted through
d. Slide the assembled gear and bushing on
a ball thrust bearing to the governor lever,
the drive shaft and check for loose fit. A slid-
which, in turn, is connected to the carburetor
ing fit of 0.0015 inch is proper, Check the face
throttle lever. A spring hooked to the gover-
of the bushing for wear through contact with
n o r lever tends to hold the governor fly-
the bushing washer; replace a worn or dam-
weights in and to hold the carburetor throttle
open. As the engine speed increases, the cen-
trifugal force of the flyweights acts against the
e. Check the ends of the hardened pins on
spring and closes the carburetor throttle to
the flyweights for wear or roughness; replace
maintain a practically constant engine speed un-
both flyweights if either is defective,
der varying load conditions. This speed can be
f. Check the yoke and bushing washer for
varied by hooking the spring in various holes
signs of wear, replace a worn yoke.
provided in the governor lever. (See figure
g. Inspect the governor gear for cracked or
chipped teeth; replace a defective gear.
h. Inspect the hardware and remaining parts
90. Governor Disassembly
for good condition; replace them as necessary.
a. Remove the governor from the engine.
b. S l i d e t h e a s s e m b l e d g e a r ( 1 9 ) a n d
thrust sleeve (11) and bearing (9) out of the
a. Install the "O" ring seal (23) in the gov-
governor housing (4).
ernor housing (4) ; start the cross shaft and
c. Spread the two flyweights (14) on the
lever into the housing.
flyweight hub (18) and slide the thrust sleeve
b. Slip the yoke (8) on the cross shaft (24)
(11) and bearing (9) off the shaft (12).
and finish pressing the shaft into the housing.
d. Using a driftpin, drive out the two pins
c. Aline the pin hole in the yoke (8) with
(15) that secure the flyweights to the fly-
that in the cross shaft (24); install the taper
weight hub (18).
e. Support the governor housing (4) on its
d. Position the flyweights (14) on the fly-
face, and, entering the housing through the
weight hub (18), and secure them with the pins
pipe fitting hole in the rear, use a driftpin to
drive out the pin (7) that secures the yoke
e. Lift up on the flyweights, and slip the
(8) to the cross shaft and lever (24), Pull out
t h r u s t sleeve (11) and bearing (9) on the
the cross shaft and lever, and remove the yoke
drive shaft (12).
from the governor housing.
f. Install the fittings in the governor hous-
ing, and install the governor.
shaft and lever (24).
g. Adjust the governor (par. 57b), C h e c k
g. Tap the expansion plug (5) out of the
speed should be 1800 rpm under load.