MTD 469 manual Servicing Your Mower, Blade Care, Replacing Drive Belt

SECTION 7: SERVICING YOUR MOWER

Blade Care

Periodically inspect the blade adapter-pulley assembly for cracks, especially if you strike a foreign object. Replace when necessary.

WARNING: When removing the cutting blade for sharpening or replacement, protect hands by using heavy gloves or a thick rag to grasp the cutting blade.

•Disconnect spark plug wire from spark plug.

•Turn mower on its side making sure that the air filter and the carburetor are up.

Refer to ‘Blade Mounting Torque’ information below.

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 parts list in the back of this manual.

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

Blade Mounting Torque:

Center bolt: 450 in.lbs. minimum, 600 in.lbs. maximum.

To Remove Blade

•Remove the hex bolt which holds the blade adapter-pulley assembly to the engine crankshaft. See Figure 13 . Remove the pulley assembly, blade and the bell support from the crankshaft.

•Remove blade from the blade adapter-pulley assembly.

Adapter-Pulley

Assembly

Blade

Blade Bell

Support

Hex Bolt

Figure 13

To Replace Blade:

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

•Also lubricate the bolt hole and the hex bolt.

•Insert the hex bolt, earlier removed, through the center hole on the blade bell support, blade and the blade adapter-pulley assembly respectively.

•Install the blade assembly on the crankshaft. Tighten the hex bolt to the recommended torque.

To Sharpen Blade:

•The blade can be sharpened with a file or on a grinding wheel. Do not attempt to sharpen the blade while it is still 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.

An unbalanced blade will cause excessive vibration when rotating at high speeds, may cause damage to the mower and/or personal injury. Test the blade by balancing it on a round shaft screwdriver or a blade balancer.

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

Replacing Drive Belt

•Remove two shoulder screws securing the front drive cover to the mower deck. See Figure 14 .

•Press inward on the sides of the front drive cover and release the tabs that secure the front drive cover to the height adjuster brackets. Remove drive cover from the mower.

•Using a torque wrench, loosen the screw holding the belt tension spring to the transmission. See Figure 14 . Do not remove the screw completely. As you loosen the screw, the tension on the belt will be released.

•Push the transmission up a little and slide the belt off the transmission pulley.

•Lift the mower to access the belt from the underside of the mower.

13