Craftsman 247.796890 - Manual (Page 9)

ADJUSTMEIMTS
CARBURETOR ADJUSTMENT
WARNING
If any adjustments are made to the engine -
while the engine if running {eg- car­
buretor), keep clear of al! moving parts
Be careful of heated surfaces and muffler.
Minor carburetor adjustment may be required to com­
pensate for differences in fuel, temperature, altitude or
load
NOTE
A DIRTY AIR CLEANER WILL CAUSE
ENGINE TO RUN ROUGH. BE CERTAIN
AIR CLEANER IS CLEAN AND ATTACH­
ED TO THE
carburetor before
ADJUSTING CARBURETOR DO NOT
MAKE UNNECESSARY ADJUSTMENTS
FACTORY SETTINGS ARE SATISFAC­
TORY FOR MOST APPLICATIONS AND
CONDITIONS.
Never attempt to change maximum engine speed It is
pre-set at the factory and should be changed only by
a qualified service technician who has the necessary
equipment,
The carburetor may need re-adjusting if engine lacks
power or does not idle properly If adjustments are
needed, proceed as follows.
To Adjust Carburetor:
1. Close needle valve (See figure 16} clockwise
(Oi' finger tight only Forcing may cause damage.
Then open 1-1/2 turns counterclockwise ik~h)
2. Start engine and allow to warm for five minutes.
3 With throttle in RUN position, close needle valve
clockwise until engine starts to lose speed
{lean mixture) Then slowly open needle valve
counterclockwise ik~N) until engine JUST BEGINS
to run unevenly This mixture should be rich enough
for best performance under load.
4 Place throttle control in IDLE position:
a If engine idles, no further adjustment is
necessary.
b. If engine idles too fast, turn idle speed
adjusting screw counterclockwise until
slower speed is obtained
c If engine dies, turn idle speed adjusting screw
1/4 turn clockwise l/^i Place throttle
control in FAST position arid restart engine,
d Move throttle control to IDLE position If
engine does not idle, repeat step c
Test the engine by operating the chipper-shredder,
If engine lends to stall or die out, it usually
indicates that the mixture is slightly lean and it may
be necessary to open iX">) the needle valve slightly
to
provide a richer mixture This richer
mixture may cause a slight unevenness in idling.
Idle Speed
Adjusting Screw Throttle
Stop
Needle Valve
FIGURE 16.
MAINTENAIMCE
Ac
WARNING
Disconnect spark plug wire and ground
it against the engine before performing
any repairs or maintenance-
ENGINE LUBRICATION
Your four cycle engine will normally consume some oil;
therefore check engine oii level regularly - approxiniateiv
every five hours of operation and before each usage
Stop engine and wait several minutes before checking
oii level, With engine level, the oil must be even with
the oil fill (refer to figure 7) Change engine oil after the
first two hours of operation, and every twenty five
hours thereafter
1. Drain oil while engine is warm
a. Remove oil drain plug Refer to figure 7
b. Tip the chipper-shredder forward, and catch oil
in a suitable container
c. When engine is drained of all oil. replace drain
plug securely.
2 Refill with fresh oil Above 32°, use oil labeled
SAE 30W or 10W30 Below 32°, use oil labeled
5W20 Capacity is 1-1/4 pints Refer to "Gas and
Oil Fill-Up" on page 6
3- Replace oil fill plug.