Drive Belt Replacement - MTD 979K Operator's Manual

• Slide the blade adapter onto the engine crankshaft.
• Place the blade on the adapter. Be certain the
blade is aligned and seated on the blade adapter
flanges.
• Place blade bell support on blade. Make sure the
notches on the blade bell support are aligned with
small holes in the blade.
• Replace hex bolt and tighten hex bolt to torque: 450
in. Ibs. min., 600 in. Ibs. max.
NOTE: To ensure safe operation of your mower,
ueriodically check the blade bolt for correct torque,
Blade
Ada
Blade Bell
_ort
Bolt
Figure 14
DriveBeltReplacement
• Disconnect the spark plug wire and ground it
against the engine.
• Drain the fuel tank or place a piece of plastic
beneath the cap to prevent gasoline leakage.
• Place shift lever in the first position and tip the
mower on its side with air filter facing up.
• Remove the center bolt which secures the blade to
the crankshaft followed by blade bell support,
blade, and blade adapter.
• Move the cutting height adjustment to the highest
position.
• Remove the three hex screws holding the baffle to
the deck and pivot baffle towards the rear of the
mower. See Figure 15.
Figure 15
Baffle
Remove the hex bolt from the rear of unit holding
the transmission to the mower housing.
See Figure 16.
Figure 16
Tilt the transmission forward and loosen the idler
pulley bolt and lock nut half a turn. See Figure 17.
Bolt and
Transmission
Figure 17
Pulley
Idler Pulley
Bracket
Belt Keeper
Bracket
-Transmission
Pulley
• Using a pair of pliers, pull back and rotate belt
keeper bracket from the slot on the idler pulley.
• Slide the belt out from between the belt keeper
bracket and the idler pulley.See Figure 17.
• Squeeze the belt together and push it forward,
while pressing the control arm inward towards the
deck and remove the six speed cable from the slot.
See Figure 18.
• Pivot the control arm down away from the pulley
and belt.
• Lift off the lower pulley assembly and remove the
old belt from around the crankshaft.
• Place the new belt over the transmission pulley.
Start the belt in the pulley groove and rotate the
pulley until the belt is seated in the transmission
pulley.
• Place the belt between the idler pulley and the belt
keeper bracket.
14