Governor - TM-10-3930-618-340055

and throttle lever (23) and press the shaft out of the

3-9. Governor

lever.

a. Description.

The engine governor is a

(7) Press the bearing, seal, and retainer off

mechanical spring loaded device installed on the engine

the lever shaft.

to prevent overspeeding. It consists of a drive gear and

(8) Remove the spider shaft bushing (35)

a set of weights arranged around a shaft in a spider

from the governor body.

assembly. The unit is mounted on the timing gear cover

(9) Press the lever shaft bottom bushing (31)

and is driven by a gear meshing with the camshaft gear.

out of the governor body.

Centrifugal force created by rotation causes the governor

d. Cleaning and Inspection.

weights to pivot outward on their retaining pins. The

(1) Wash all parts in cleaning solvent (Spec.

outward movement of the weights pushes a thrust sleeve

P-S-661) and thoroughly dry with compressed air.

against a yoke, which in turn, transfers this movement

(2) Check lever shaft and bearing for worn

through the governor control rod to the throttle valve in

areas and score marks. Replace if lever shaft does not

the carburetor. The governor weights move outward

rotate freely in the governor body.

until the pressure on the thrust sleeve is strong enough

(3) Replace the lever shaft oil seal.

to overcome the spring tension on the throttle lever.

(4) Slide thrust sleeve and bearing on the

When this condition occurs, governor force, through the

spider shaft and check for freeness.

control rod to the throttle valve, prevents the entrance of

(5) Check the drive gear (43) for worn or

more fuel to the manifold, thus preventing the engine

chipped teeth. Check the gear bearing surface for score

from exceeding its maximum governed speed of 2200

marks. Replace the gear if necessary.

rpm.

(6) If the governor weights (39) are too loose

b. Removal.

or bind on the pivot pins, make the necessary repairs, or

(1) Clean outside of the governor housing and

replace the assembly.

the surrounding area to be certain that no loose dirt will

(7) Check the drive gear bearing and the

enter the governor assembly.

thrust washer for worn spots or score marks. I' the

(2) Remove the ignition coil from the adapter

bearing is loose, install a new bearing in the adapter.

cover (TM 10-3930-618-20).

(8) Replace the governor spring (17) if it is

(3) Remove the governor spring (17, fig. 3-8)

worn or weak.

from the adjusting screw (18) and disconnect the throttle

(9) Install new gasket.

lever (23) from the control rod 13).

e. Assembly.

(4) Remove the two capscrews from the

(1) To replace the adapter bearing (9), locate

adapter assembly (11) mounting flange.

Lift the

the bearing with the oil hole up and press into place to

governor body away from the timing gear housing.

the same position as the bearing which was removed.

(5) Slide the thrust bearing and sleeve (38) off

(2) Press bearing (28) on the lever shaft (20)

the weight assembly shaft (40) and then work the drive

until it seats on the snapring (29) and then follow with the

gear (43) free of the adapter.

oil seal (26) and retainer (27).

(6) Remove the two capscrews (13) and

(3) Install the throttle lever (23) on the lever

lockwashers (12) attaching adapter (11) to body (30) and

shaft (20) and secure both parts with the roll pin (24).

timing gear housing, and remove the adapter and thrust

(4) Press the spider shaft bushing (35), into

washer t 10).

the governor housing flush with the open end of the bore.

c. Disassembly.

Normal clearance between the bushing and the shaft is

(1) Remove the adapter cover to remove the

0.002 inch to 0.004 inch.

adapter bearing 19i.

(5) Press the lever shaft bushing (31) into the

(2) To remove the governor weights (39) from

governor housing; but, do not press all the way in at this

the spider assembly (40). slip the pin clips (42) from the

time.

governor weight pivot pins, drive out the pins and remove

(6) Hold the yoke (36) in the governor

the weight from the spider.

housing, install the lever (23) and shaft (20), sliding the

(3) Press the drive gear (43) from the spider

shaft through the yoke.

shaft (40).

(7) Position the yoke on the shaft. install and

(4) Remove the two fasteners (37) which

tighten the fasteners (37).

secure the yoke (36) to the lever shaft (20).

(8) Continue pressing the lever shaft bushing

(5) Pull the lever shaft out of the governor

into the governor housing until there is between 0.005-

body along with the bearing (28), seal (26), and retainer

inch and 0.015-inch end plan. Then paint over the

(27). Remove the yoke from the governor bode.

bushing with a sealing compound.

(6) Drive the pin (24) out of the lever shaft

3-12