TM 10-4320-344-24
3.8.6 Governor Maintenance. Model 609-A. (Continued)
To adjust the A potentiometer, engine must be disconnected from pump
impeller and running unloaded.
b.
c .
d .
e .
f .
g .
h.
The amount of droop for a given setting depends on pick-up frequency
and no load to full load actuator shaft rotation.
Lower pick-up
f r e q u e n c y o r s m a l l e r s h a f t r o t a t i o n r e s u l t s i n l e s s d r o o p:
Set potentiometers (pot) as indicated below:
A ( 5 ) a t 3 o ’ c l o c k
G a i n ( 6 ) a t 9 o ’ c l o ck
D ( 7 ) a t 1 0 o ’ c l o ck
I ( 8 ) a t 8 o ’ c l o ck
L (9) is factory adjusted and should be at about 10 o’clock
D r o o p ( 1 0 ) a t 9 o ’ c l o c k .
Refer to TM 10-4320-344-10 and start engine.
Adjust controller “SPEED” pot (11) until engine is operating at desired speed.
Turn the A pot (5) slowly to the right until the governor actuator oscillates
( j i g g l e s ) r a p i d l y.
Turn the A pot (5) slowly to the left until the rapid oscillation just stops.
Excite governor actuator by tapping governor actuator lever.
If the governor
actuator lever oscillates rapidly, turn the A pot (5) slowly to the left until
the rapid oscillation just stops.
Hunting is when the engine RPM is not stable (moving up and down).
If governor is hunting, turn GAIN pot (6) slowly to the left until it is
s t a b l e.
A moving governor actuator lever and a constant speed means unit is governing
and not hunting.
i .
If governor is stable, turn GAIN pot (6) slowly to the right until governor
starts to hunt, then turn GAIN pot (6) slowly to the left until governor is
s t a b l e.
j .
Excite governor by tapping governor actuator lever.
Engine should return
quickly to its command speed without hunting.
k.
Turn D pot (7) to the right until governor actuator lever begins to hunt.
(Governor may have to be excited by tapping governor actuator lever.)
l .
Turn D pot (7) slowly to the left until engine is stable.
m.
Refer to TM 10-4320-344-10 and turn engine switch off.
Let engine slow down
to about half-speed.
n.
Refer to TM 10-4320-344-10 and turn engine switch on.
Observe engine RPM.
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