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4. Add a full-rated load to the generating set and
compare lower speed and voltage with those
shown in the charts. If operation does not remain
in these limits, check governor linkage and gov-
ernor spring, and, if necessary, follow preceding
procedure again.
5. Check and, if necessary, adjust governor sensitiv-
ity (Sensitivity
Adjustment).
Sensitivity Adjustment
1. Start generating set and allow to warm up.
2. Check voltage and speed, first without load and
then with a full load. See voltage and speed
charts.
3. Increase sensitivity (closer regulation) by shifting
adjusting clip toward governor shaft (Figure 33).
Move clip away from governor shaft to decrease
sensitivity.
Too much sensitivity causes the engine to hunt. Too little
sensitivity results in too much speed dilference between no-
load and full-load conditions.
4. A change in sensitivity adjustment usually re-
quires a compensating speed adjustment (spring
tension). Then proceed to Speed Booster.
Speed Booster
1. After sensitivity adj ustment, connect booster exter-
nal spring to slide on governor link (Figure 33).
2. With generating set running at no load, move
adjustable slide to point where there is no tension
on spring.
3. Apply full-rated load to generating set.
4. If the speed increases more than the no-load fre-
quency when the load is applied, lessen the speed
booster's internal spring tension. To change ten-
sion, pull out the spring bracket and move the pin
to a different hole (Figure 33). If speed decreases
when the load is applied, increase the booster's
internal spring tension.
BREAKER POINTS
1. Remove the two screws and the cover on the
breaker box.
2. Remove the two spark plugs so engine can be
easily rotated by hand.
3. Turn flywheel in a clockwise direction approxi-
mately 1/4 turn after top center (TC).
4. To adjust gap, refer to Figure 34. Loosen screws
(A) and turn cam (B) until point gap measures
0.020 inch (0.508 mm) with a flat thickness
gauge. Retighten screws (A) and recheck gap.
5. If points are slightly burned, dress smooth with a
file or fine stone. If points appear to be burned
and pitted, replace with a new set.
6. Replace spark plugs and breaker box cover.
PLACE A DROP OF
LIGHT O I L ON
BREAKER ARM PIVOT
SHAFT EVERY TIME
POINTS ARE
R E P L A C E D
TO ADJUST GAP
LOOSEN SCREWS®
TURN C A M ®
SET B R E A K E R POINT
GAP WIDTH A T 0.020
(0.506 mm)
LOOSEN THESE
SCREWS TO ADJUST
POSITION OF
BREAKER BOX
RETARD SPARK -
-ADVANCE SPARK
R E F E R E N C E MARK
FIGURE 34. SETTING BREAKER POINTS
IGNITION TIMING
Both spark plugs fire simultaneously, thus the need
f o r a d i s t r i b u t o r
is e l i m i n a t e d . S p a r k a d -
vance is set at 19° BTC (before top center) and should
be m a i n t a i n e d
f o r b e s t e n g i n e
p e r f o r -
mance. See Figure 35. Always check timing after
replacing i g n i t i o n p o i n t s or if n o t i c i n g p o o r
engine performance. Proceed as follows:
Timing Procedure—Engine Running
1. To accurately check the ignition timing, use a
timing light when the engine is running. Connect
the timing light according to its manufacturer's
G N I T I O N T I M I N G
M A R K
C H E C K T I M I N G
T H R O U G H
H O L E IN R I G H T S I D E O F
B L O W E R
H O U S I N G
FIGURE 35. IGNITION TIMING MARK
22
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