Craftsman 247.388250 owner manual Servicing Blade, Engine Adjustments

Servicing Blade

To Remove Blade

Remove the bolt, and the blade bell support. which holds the blade and adapter to the engine crankshaft. See Figure 14.

Remove the blade and the adapter from the crankshaft.

To Replace Blade:

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.

Install the blade adapter on the crankshaft with the "star" away from the engine. See Figure 14.

Blade Adapter

Crankshaft

Blade

Blade Bell

Hex Bolt

Support

Figure 14

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

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

the bell support.

•Insert the hex bolt through the blade assembly. Figure 14 shows the correct order of assembly.

•Use block of wood to hold blade while you tighten the bolt clockwise. Follow the

recommended torque for the bolt which is 450- 600 in.-Ibs.

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.

_.	your unit, all nuts and bolts must be
	WARNING: To ensure safe operation of
	checked periodicallyfor correct tightness.

To Sharpen Blade:

The blade can be sharpened witha file or on a gdnding wheel. Do not attempt to sharpen while on the mower.

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.

Test the blade by balancing it on a round shaft screwdriver or a blade balancer. See Figure 15. If the blade is not balanced, remove metal from the heavy side until it balances evenly.

1.Insert screw driver through hole

2.Blade should be parallelto ground

Screw

Driver_ Blade

Ground

Figure 15

Engine Adjustments

A WARNING: Do not make unnecessary adjustments on the engine. Factory settings are satisfactoryfor 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.

Carburetor

The carburetor has been pre-set at the factory and should not require adLustment.

•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.

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.

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