Snapper 1650 - Carburetor & Governor Adjustments

Fig. 24 — Carburetor Adjustments
1. Idle Fuel Screw
2. Idle Speed Screw
3. Main Fuel Screw
Fig. 25 — Governor Adjustment
1. Governor Arm 3. Hex Nut
2. Cross Shaft 4. Governor Control Bracket
5. Spring
throttle and full load, turn main fuel screw in until
engine slows (lean setting) then turn screw out until
engine regains speed and then starts to slow down
(overrich setting). Turn screw back in until it is
positioned halfway between lean and overrich set¬
tings — when properly adjusted engine will ac¬
celerate smoothly and operate with steady governor
action.
IDLE ADJUSTMENT
Rough idle is usually caused by idle speed being
set too low. Turn idle speed screw, No. 2, in clock¬
wise direction to increase speed. If engine still
idles poorly after speed is increased, stop engine and
turn idle fuel screw. No. 1, all the way in (clock¬
wise) until it bottoms lightly (do not force screw),
then back out 1 -1 /4 turns. Restart engine and check
idle — turn needle in or out (1/4 turn at a time)
until smoothest idle is achieved. Idle speed should
be 2100-2300 rpm.
NOTE: If these adjustments do not correct
carburetor problems, carburetor should be
removed and overhauled.
GOVERNOR ADJUSTMENT
The governor functions to maintain engine speed
under changing load conditions and also acts as a
speed limiting device. Governors are set at the
factory and further adjustment should not be re¬
quired unless linkage works loose or becomes dis¬
connected. Readjustment should be made if engine
surges with changing load or if speed drops con¬
siderably when a normal load is applied.
INITIAL ADJUSTMENT
With engine stopped, loosen (do not remove) hex
nut, No. 3, Fig. 25, securing governor arm, No. 1, to
governor cross shaft. No. 2. Grasp end of cross shaft
with pliers and turn shaft as far as possible in
counterclockwise direction — tab on shaft will stop
internally against governor gear mechanism. Hold
shaft in this position, pull governor arm all the way
away from carburetor then retighten governor arm
nut to complete initial adjustment.
SPEED ADJUSTMENT
Maximum allowable speed is 3600 rpm. This speed
must not be exceeded. If overspeed condition is
suspected, check rpm's with hand tachometer and
readjust as follows:
Adjust high speed stop screw. No. 2, Fig. 26, until
correct maximum speed is attained.
Fig. 26 — Governor Adjustment
1. High Speed Bracket
2. High Speed Stop Screw
3. Throttle Control Cable — Behind Choke Cable
4. Choke Cable
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