Craftsman 247.38824 Benutzerhandbuch

15

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Remove the bolt and blade bell support which 
hold the blade and adapter to the engine 
crankshaft. See Figure 16.

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Remove the blade and adapter from the 
crankshaft.

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Before reinstalling the blade and the blade 
adapter to the unit, lubricate the engine 
crankshaft and the inner surface of the blade 
adapter with light oil.

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Install the blade adapter on the crankshaft with 
the “star” away from the engine. See Figure 16.

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Place the new blade with the side marked 
bottom (or with part number) facing away from 
the adapter.

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Place the bell support next. Make  sure to align 
the tabs in the holes of the blade with the hole in 
the bell support. 

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Insert the hex bolt through the blade assembly. 
Figure 16 shows the correct order of assembly.

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Use block of wood to hold blade again while you 
tighten the bolt clockwise. Follow the 
recommended torque for the bolt which is 450-
600 in.-lbs. 

IMPORTANT: The bolt, used to secure the blade to 
the engine, is specially heat-treated. Do not 
substitute. To order replacement bolt, refer to the 
Repair Parts section of this manual.

 To ensure safe operation of 

your unit, all nuts and bolts must be 
checked periodically for correct tightness.

The blade can be sharpened with a file or on a grinding 
wheel. Do not attempt to sharpen while on the mower.
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Follow the original angle of grind as a guide. 
Make sure that each cutting edge receives an 
equal amount of grinding to prevent an 
unbalanced blade. 

NOTE: An unbalanced blade will cause excessive 
vibration when rotating at high speeds, may cause 
damage to the mower and could break, causing 
personal injury.
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Test  the blade by balancing it  on a round shaft 
screwdriver or a blade balancer. See Figure 17.  

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If the blade is not balanced, remove metal from 
the heavy side until it balances evenly.

WARNING: Do not make unnecessary 
adjustments on the engine. Factory settings 
are satisfactory for most conditions.
If any adjustments are made to the engine 
while the engine is running, keep clear of all 
moving parts. Be careful of heated 
surfaces and muffler.  Keep your hands 
away from  these parts.

The carburetor has been pre-set at the factory and 
should not require adjustment.
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If the  engine on your mower does not operate 
properly due to suspected carburetor problems, 
take your lawn mower to your nearest SEARS 
service center. 

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Engine performance may be affected in altitudes 
above 4000 feet. To improve engine 
performance, install  a high altitude adjustment 
kit, available at the SEARS service center.

NOTE: A dirty air cleaner will cause an engine to run 
rough. Be certain air cleaner is clean and attached to 
the carburetor.